diff --git a/rpc/client.go b/rpc/client.go index 6254c95ffd..02029dc8f6 100644 --- a/rpc/client.go +++ b/rpc/client.go @@ -18,17 +18,13 @@ package rpc import ( "bytes" - "container/list" "context" "encoding/json" "errors" "fmt" - "net" "net/url" "reflect" "strconv" - "strings" - "sync" "sync/atomic" "time" @@ -39,13 +35,14 @@ var ( ErrClientQuit = errors.New("client is closed") ErrNoResult = errors.New("no result in JSON-RPC response") ErrSubscriptionQueueOverflow = errors.New("subscription queue overflow") + errClientReconnected = errors.New("client reconnected") + errDead = errors.New("connection lost") ) const ( // Timeouts tcpKeepAliveInterval = 30 * time.Second - defaultDialTimeout = 10 * time.Second // used when dialing if the context has no deadline - defaultWriteTimeout = 10 * time.Second // used for calls if the context has no deadline + defaultDialTimeout = 10 * time.Second // used if context has no deadline subscribeTimeout = 5 * time.Second // overall timeout eth_subscribe, rpc_modules calls ) @@ -76,56 +73,57 @@ type BatchElem struct { Error error } -// A value of this type can a JSON-RPC request, notification, successful response or -// error response. Which one it is depends on the fields. -type jsonrpcMessage struct { - Version string `json:"jsonrpc"` - ID json.RawMessage `json:"id,omitempty"` - Method string `json:"method,omitempty"` - Params json.RawMessage `json:"params,omitempty"` - Error *jsonError `json:"error,omitempty"` - Result json.RawMessage `json:"result,omitempty"` -} +// Client represents a connection to an RPC server. +type Client struct { + idgen func() ID // for subscriptions + isHTTP bool + services *serviceRegistry -func (msg *jsonrpcMessage) isNotification() bool { - return msg.ID == nil && msg.Method != "" -} + idCounter uint32 -func (msg *jsonrpcMessage) isResponse() bool { - return msg.hasValidID() && msg.Method == "" && len(msg.Params) == 0 -} + // This function, if non-nil, is called when the connection is lost. + reconnectFunc reconnectFunc + + // writeConn is used for writing to the connection on the caller's goroutine. It should + // only be accessed outside of dispatch, with the write lock held. The write lock is + // taken by sending on requestOp and released by sending on sendDone. + writeConn jsonWriter -func (msg *jsonrpcMessage) hasValidID() bool { - return len(msg.ID) > 0 && msg.ID[0] != '{' && msg.ID[0] != '[' + // for dispatch + close chan struct{} + closing chan struct{} // closed when client is quitting + didClose chan struct{} // closed when client quits + reconnected chan ServerCodec // where write/reconnect sends the new connection + readOp chan readOp // read messages + readErr chan error // errors from read + reqInit chan *requestOp // register response IDs, takes write lock + reqSent chan error // signals write completion, releases write lock + reqTimeout chan *requestOp // removes response IDs when call timeout expires } -func (msg *jsonrpcMessage) String() string { - b, _ := json.Marshal(msg) - return string(b) +type reconnectFunc func(ctx context.Context) (ServerCodec, error) + +type clientContextKey struct{} + +type clientConn struct { + codec ServerCodec + handler *handler } -// Client represents a connection to an RPC server. -type Client struct { - idCounter uint32 - connectFunc func(ctx context.Context) (net.Conn, error) - isHTTP bool +func (c *Client) newClientConn(conn ServerCodec) *clientConn { + ctx := context.WithValue(context.Background(), clientContextKey{}, c) + handler := newHandler(ctx, conn, c.idgen, c.services) + return &clientConn{conn, handler} +} - // writeConn is only safe to access outside dispatch, with the - // write lock held. The write lock is taken by sending on - // requestOp and released by sending on sendDone. - writeConn net.Conn +func (cc *clientConn) close(err error, inflightReq *requestOp) { + cc.handler.close(err, inflightReq) + cc.codec.Close() +} - // for dispatch - close chan struct{} - closing chan struct{} // closed when client is quitting - didClose chan struct{} // closed when client quits - reconnected chan net.Conn // where write/reconnect sends the new connection - readErr chan error // errors from read - readResp chan []*jsonrpcMessage // valid messages from read - requestOp chan *requestOp // for registering response IDs - sendDone chan error // signals write completion, releases write lock - respWait map[string]*requestOp // active requests - subs map[string]*ClientSubscription // active subscriptions +type readOp struct { + msgs []*jsonrpcMessage + batch bool } type requestOp struct { @@ -135,9 +133,14 @@ type requestOp struct { sub *ClientSubscription // only set for EthSubscribe requests } -func (op *requestOp) wait(ctx context.Context) (*jsonrpcMessage, error) { +func (op *requestOp) wait(ctx context.Context, c *Client) (*jsonrpcMessage, error) { select { case <-ctx.Done(): + // Send the timeout to dispatch so it can remove the request IDs. + select { + case c.reqTimeout <- op: + case <-c.closing: + } return nil, ctx.Err() case resp := <-op.resp: return resp, op.err @@ -181,36 +184,57 @@ func DialContext(ctx context.Context, rawurl string) (*Client, error) { } } -func newClient(initctx context.Context, connectFunc func(context.Context) (net.Conn, error)) (*Client, error) { - conn, err := connectFunc(initctx) +// Client retrieves the client from the context, if any. This can be used to perform +// 'reverse calls' in a handler method. +func ClientFromContext(ctx context.Context) (*Client, bool) { + client, ok := ctx.Value(clientContextKey{}).(*Client) + return client, ok +} + +func newClient(initctx context.Context, connect reconnectFunc) (*Client, error) { + conn, err := connect(initctx) if err != nil { return nil, err } + c := initClient(conn, randomIDGenerator(), new(serviceRegistry)) + c.reconnectFunc = connect + return c, nil +} + +func initClient(conn ServerCodec, idgen func() ID, services *serviceRegistry) *Client { _, isHTTP := conn.(*httpConn) c := &Client{ - writeConn: conn, + idgen: idgen, isHTTP: isHTTP, - connectFunc: connectFunc, + services: services, + writeConn: conn, close: make(chan struct{}), closing: make(chan struct{}), didClose: make(chan struct{}), - reconnected: make(chan net.Conn), + reconnected: make(chan ServerCodec), + readOp: make(chan readOp), readErr: make(chan error), - readResp: make(chan []*jsonrpcMessage), - requestOp: make(chan *requestOp), - sendDone: make(chan error, 1), - respWait: make(map[string]*requestOp), - subs: make(map[string]*ClientSubscription), + reqInit: make(chan *requestOp), + reqSent: make(chan error, 1), + reqTimeout: make(chan *requestOp), } if !isHTTP { go c.dispatch(conn) } - return c, nil + return c +} + +// RegisterName creates a service for the given receiver type under the given name. When no +// methods on the given receiver match the criteria to be either a RPC method or a +// subscription an error is returned. Otherwise a new service is created and added to the +// service collection this client provides to the server. +func (c *Client) RegisterName(name string, receiver interface{}) error { + return c.services.registerName(name, receiver) } func (c *Client) nextID() json.RawMessage { id := atomic.AddUint32(&c.idCounter, 1) - return []byte(strconv.FormatUint(uint64(id), 10)) + return strconv.AppendUint(nil, uint64(id), 10) } // SupportedModules calls the rpc_modules method, retrieving the list of @@ -267,7 +291,7 @@ func (c *Client) CallContext(ctx context.Context, result interface{}, method str } // dispatch has accepted the request and will close the channel when it quits. - switch resp, err := op.wait(ctx); { + switch resp, err := op.wait(ctx, c); { case err != nil: return err case resp.Error != nil: @@ -325,7 +349,7 @@ func (c *Client) BatchCallContext(ctx context.Context, b []BatchElem) error { // Wait for all responses to come back. for n := 0; n < len(b) && err == nil; n++ { var resp *jsonrpcMessage - resp, err = op.wait(ctx) + resp, err = op.wait(ctx, c) if err != nil { break } @@ -352,6 +376,22 @@ func (c *Client) BatchCallContext(ctx context.Context, b []BatchElem) error { return err } +// Notify sends a notification, i.e. a method call that doesn't expect a response. +func (c *Client) Notify(ctx context.Context, method string, args ...interface{}) error { + op := new(requestOp) + msg, err := c.newMessage(method, args...) + if err != nil { + return err + } + msg.ID = nil + + if c.isHTTP { + return c.sendHTTP(ctx, op, msg) + } else { + return c.send(ctx, op, msg) + } +} + // EthSubscribe registers a subscripion under the "eth" namespace. func (c *Client) EthSubscribe(ctx context.Context, channel interface{}, args ...interface{}) (*ClientSubscription, error) { return c.Subscribe(ctx, "eth", channel, args...) @@ -402,30 +442,30 @@ func (c *Client) Subscribe(ctx context.Context, namespace string, channel interf if err := c.send(ctx, op, msg); err != nil { return nil, err } - if _, err := op.wait(ctx); err != nil { + if _, err := op.wait(ctx, c); err != nil { return nil, err } return op.sub, nil } func (c *Client) newMessage(method string, paramsIn ...interface{}) (*jsonrpcMessage, error) { - params, err := json.Marshal(paramsIn) - if err != nil { - return nil, err + msg := &jsonrpcMessage{Version: vsn, ID: c.nextID(), Method: method} + if paramsIn != nil { // prevent sending "params":null + var err error + if msg.Params, err = json.Marshal(paramsIn); err != nil { + return nil, err + } } - return &jsonrpcMessage{Version: "2.0", ID: c.nextID(), Method: method, Params: params}, nil + return msg, nil } // send registers op with the dispatch loop, then sends msg on the connection. // if sending fails, op is deregistered. func (c *Client) send(ctx context.Context, op *requestOp, msg interface{}) error { select { - case c.requestOp <- op: - log.Trace("", "msg", log.Lazy{Fn: func() string { - return fmt.Sprint("sending ", msg) - }}) + case c.reqInit <- op: err := c.write(ctx, msg) - c.sendDone <- err + c.reqSent <- err return err case <-ctx.Done(): // This can happen if the client is overloaded or unable to keep up with @@ -433,25 +473,17 @@ func (c *Client) send(ctx context.Context, op *requestOp, msg interface{}) error return ctx.Err() case <-c.closing: return ErrClientQuit - case <-c.didClose: - return ErrClientQuit } } func (c *Client) write(ctx context.Context, msg interface{}) error { - deadline, ok := ctx.Deadline() - if !ok { - deadline = time.Now().Add(defaultWriteTimeout) - } // The previous write failed. Try to establish a new connection. if c.writeConn == nil { if err := c.reconnect(ctx); err != nil { return err } } - c.writeConn.SetWriteDeadline(deadline) - err := json.NewEncoder(c.writeConn).Encode(msg) - c.writeConn.SetWriteDeadline(time.Time{}) + err := c.writeConn.Write(ctx, msg) if err != nil { c.writeConn = nil } @@ -459,9 +491,18 @@ func (c *Client) write(ctx context.Context, msg interface{}) error { } func (c *Client) reconnect(ctx context.Context) error { - newconn, err := c.connectFunc(ctx) + if c.reconnectFunc == nil { + return errDead + } + + if _, ok := ctx.Deadline(); !ok { + var cancel func() + ctx, cancel = context.WithTimeout(ctx, defaultDialTimeout) + defer cancel() + } + newconn, err := c.reconnectFunc(ctx) if err != nil { - log.Trace(fmt.Sprintf("reconnect failed: %v", err)) + log.Trace("RPC client reconnect failed", "err", err) return err } select { @@ -477,322 +518,107 @@ func (c *Client) reconnect(ctx context.Context) error { // dispatch is the main loop of the client. // It sends read messages to waiting calls to Call and BatchCall // and subscription notifications to registered subscriptions. -func (c *Client) dispatch(conn net.Conn) { - // Spawn the initial read loop. - go c.read(conn) - +func (c *Client) dispatch(codec ServerCodec) { var ( - lastOp *requestOp // tracks last send operation - requestOpLock = c.requestOp // nil while the send lock is held - reading = true // if true, a read loop is running + lastOp *requestOp // tracks last send operation + reqInitLock = c.reqInit // nil while the send lock is held + conn = c.newClientConn(codec) + reading = true ) - defer close(c.didClose) defer func() { close(c.closing) - c.closeRequestOps(ErrClientQuit) - conn.Close() if reading { - // Empty read channels until read is dead. - for { - select { - case <-c.readResp: - case <-c.readErr: - return - } - } + conn.close(ErrClientQuit, nil) + c.drainRead() } + close(c.didClose) }() + // Spawn the initial read loop. + go c.read(codec) + for { select { case <-c.close: return - // Read path. - case batch := <-c.readResp: - for _, msg := range batch { - switch { - case msg.isNotification(): - log.Trace("", "msg", log.Lazy{Fn: func() string { - return fmt.Sprint("<-readResp: notification ", msg) - }}) - c.handleNotification(msg) - case msg.isResponse(): - log.Trace("", "msg", log.Lazy{Fn: func() string { - return fmt.Sprint("<-readResp: response ", msg) - }}) - c.handleResponse(msg) - default: - log.Debug("", "msg", log.Lazy{Fn: func() string { - return fmt.Sprint("<-readResp: dropping weird message", msg) - }}) - // TODO: maybe close - } + // Read path: + case op := <-c.readOp: + if op.batch { + conn.handler.handleBatch(op.msgs) + } else { + conn.handler.handleMsg(op.msgs[0]) } case err := <-c.readErr: - log.Debug("<-readErr", "err", err) - c.closeRequestOps(err) - conn.Close() + conn.handler.log.Debug("RPC connection read error", "err", err) + conn.close(err, lastOp) reading = false - case newconn := <-c.reconnected: - log.Debug("<-reconnected", "reading", reading, "remote", conn.RemoteAddr()) + // Reconnect: + case newcodec := <-c.reconnected: + log.Debug("RPC client reconnected", "reading", reading, "conn", newcodec.RemoteAddr()) if reading { - // Wait for the previous read loop to exit. This is a rare case. - conn.Close() - <-c.readErr + // Wait for the previous read loop to exit. This is a rare case which + // happens if this loop isn't notified in time after the connection breaks. + // In those cases the caller will notice first and reconnect. Closing the + // handler terminates all waiting requests (closing op.resp) except for + // lastOp, which will be transferred to the new handler. + conn.close(errClientReconnected, lastOp) + c.drainRead() } - go c.read(newconn) + go c.read(newcodec) reading = true - conn = newconn - - // Send path. - case op := <-requestOpLock: - // Stop listening for further send ops until the current one is done. - requestOpLock = nil + conn = c.newClientConn(newcodec) + // Re-register the in-flight request on the new handler + // because that's where it will be sent. + conn.handler.addRequestOp(lastOp) + + // Send path: + case op := <-reqInitLock: + // Stop listening for further requests until the current one has been sent. + reqInitLock = nil lastOp = op - for _, id := range op.ids { - c.respWait[string(id)] = op - } + conn.handler.addRequestOp(op) - case err := <-c.sendDone: + case err := <-c.reqSent: if err != nil { - // Remove response handlers for the last send. We remove those here - // because the error is already handled in Call or BatchCall. When the - // read loop goes down, it will signal all other current operations. - for _, id := range lastOp.ids { - delete(c.respWait, string(id)) - } + // Remove response handlers for the last send. When the read loop + // goes down, it will signal all other current operations. + conn.handler.removeRequestOp(lastOp) } - // Listen for send ops again. - requestOpLock = c.requestOp + // Let the next request in. + reqInitLock = c.reqInit lastOp = nil - } - } -} - -// closeRequestOps unblocks pending send ops and active subscriptions. -func (c *Client) closeRequestOps(err error) { - didClose := make(map[*requestOp]bool) - for id, op := range c.respWait { - // Remove the op so that later calls will not close op.resp again. - delete(c.respWait, id) - - if !didClose[op] { - op.err = err - close(op.resp) - didClose[op] = true + case op := <-c.reqTimeout: + conn.handler.removeRequestOp(op) } } - for id, sub := range c.subs { - delete(c.subs, id) - sub.quitWithError(err, false) - } -} - -func (c *Client) handleNotification(msg *jsonrpcMessage) { - if !strings.HasSuffix(msg.Method, notificationMethodSuffix) { - log.Debug("dropping non-subscription message", "msg", msg) - return - } - var subResult struct { - ID string `json:"subscription"` - Result json.RawMessage `json:"result"` - } - if err := json.Unmarshal(msg.Params, &subResult); err != nil { - log.Debug("dropping invalid subscription message", "msg", msg) - return - } - if c.subs[subResult.ID] != nil { - c.subs[subResult.ID].deliver(subResult.Result) - } -} - -func (c *Client) handleResponse(msg *jsonrpcMessage) { - op := c.respWait[string(msg.ID)] - if op == nil { - log.Debug("unsolicited response", "msg", msg) - return - } - delete(c.respWait, string(msg.ID)) - // For normal responses, just forward the reply to Call/BatchCall. - if op.sub == nil { - op.resp <- msg - return - } - // For subscription responses, start the subscription if the server - // indicates success. EthSubscribe gets unblocked in either case through - // the op.resp channel. - defer close(op.resp) - if msg.Error != nil { - op.err = msg.Error - return - } - if op.err = json.Unmarshal(msg.Result, &op.sub.subid); op.err == nil { - go op.sub.start() - c.subs[op.sub.subid] = op.sub - } } -// Reading happens on a dedicated goroutine. - -func (c *Client) read(conn net.Conn) error { - var ( - buf json.RawMessage - dec = json.NewDecoder(conn) - ) - readMessage := func() (rs []*jsonrpcMessage, err error) { - buf = buf[:0] - if err = dec.Decode(&buf); err != nil { - return nil, err - } - if isBatch(buf) { - err = json.Unmarshal(buf, &rs) - } else { - rs = make([]*jsonrpcMessage, 1) - err = json.Unmarshal(buf, &rs[0]) - } - return rs, err - } - +// drainRead drops read messages until an error occurs. +func (c *Client) drainRead() { for { - resp, err := readMessage() - if err != nil { - c.readErr <- err - return err - } - c.readResp <- resp - } -} - -// Subscriptions. - -// A ClientSubscription represents a subscription established through EthSubscribe. -type ClientSubscription struct { - client *Client - etype reflect.Type - channel reflect.Value - namespace string - subid string - in chan json.RawMessage - - quitOnce sync.Once // ensures quit is closed once - quit chan struct{} // quit is closed when the subscription exits - errOnce sync.Once // ensures err is closed once - err chan error -} - -func newClientSubscription(c *Client, namespace string, channel reflect.Value) *ClientSubscription { - sub := &ClientSubscription{ - client: c, - namespace: namespace, - etype: channel.Type().Elem(), - channel: channel, - quit: make(chan struct{}), - err: make(chan error, 1), - in: make(chan json.RawMessage), - } - return sub -} - -// Err returns the subscription error channel. The intended use of Err is to schedule -// resubscription when the client connection is closed unexpectedly. -// -// The error channel receives a value when the subscription has ended due -// to an error. The received error is nil if Close has been called -// on the underlying client and no other error has occurred. -// -// The error channel is closed when Unsubscribe is called on the subscription. -func (sub *ClientSubscription) Err() <-chan error { - return sub.err -} - -// Unsubscribe unsubscribes the notification and closes the error channel. -// It can safely be called more than once. -func (sub *ClientSubscription) Unsubscribe() { - sub.quitWithError(nil, true) - sub.errOnce.Do(func() { close(sub.err) }) -} - -func (sub *ClientSubscription) quitWithError(err error, unsubscribeServer bool) { - sub.quitOnce.Do(func() { - // The dispatch loop won't be able to execute the unsubscribe call - // if it is blocked on deliver. Close sub.quit first because it - // unblocks deliver. - close(sub.quit) - if unsubscribeServer { - sub.requestUnsubscribe() - } - if err != nil { - if err == ErrClientQuit { - err = nil // Adhere to subscription semantics. - } - sub.err <- err + select { + case <-c.readOp: + case <-c.readErr: + return } - }) -} - -func (sub *ClientSubscription) deliver(result json.RawMessage) (ok bool) { - select { - case sub.in <- result: - return true - case <-sub.quit: - return false } } -func (sub *ClientSubscription) start() { - sub.quitWithError(sub.forward()) -} - -func (sub *ClientSubscription) forward() (err error, unsubscribeServer bool) { - cases := []reflect.SelectCase{ - {Dir: reflect.SelectRecv, Chan: reflect.ValueOf(sub.quit)}, - {Dir: reflect.SelectRecv, Chan: reflect.ValueOf(sub.in)}, - {Dir: reflect.SelectSend, Chan: sub.channel}, - } - buffer := list.New() - defer buffer.Init() +// read decodes RPC messages from a codec, feeding them into dispatch. +func (c *Client) read(codec ServerCodec) { for { - var chosen int - var recv reflect.Value - if buffer.Len() == 0 { - // Idle, omit send case. - chosen, recv, _ = reflect.Select(cases[:2]) - } else { - // Non-empty buffer, send the first queued item. - cases[2].Send = reflect.ValueOf(buffer.Front().Value) - chosen, recv, _ = reflect.Select(cases) + msgs, batch, err := codec.Read() + if _, ok := err.(*json.SyntaxError); ok { + codec.Write(context.Background(), errorMessage(&parseError{err.Error()})) } - - switch chosen { - case 0: // <-sub.quit - return nil, false - case 1: // <-sub.in - val, err := sub.unmarshal(recv.Interface().(json.RawMessage)) - if err != nil { - return err, true - } - if buffer.Len() == maxClientSubscriptionBuffer { - return ErrSubscriptionQueueOverflow, true - } - buffer.PushBack(val) - case 2: // sub.channel<- - cases[2].Send = reflect.Value{} // Don't hold onto the value. - buffer.Remove(buffer.Front()) + if err != nil { + c.readErr <- err + return } + c.readOp <- readOp{msgs, batch} } } - -func (sub *ClientSubscription) unmarshal(result json.RawMessage) (interface{}, error) { - val := reflect.New(sub.etype) - err := json.Unmarshal(result, val.Interface()) - return val.Elem().Interface(), err -} - -func (sub *ClientSubscription) requestUnsubscribe() error { - var result interface{} - return sub.client.Call(&result, sub.namespace+unsubscribeMethodSuffix, sub.subid) -} diff --git a/rpc/client_test.go b/rpc/client_test.go index a8195c0af8..80fe29f824 100644 --- a/rpc/client_test.go +++ b/rpc/client_test.go @@ -35,13 +35,13 @@ import ( ) func TestClientRequest(t *testing.T) { - server := newTestServer("service", new(Service)) + server := newTestServer() defer server.Stop() client := DialInProc(server) defer client.Close() var resp Result - if err := client.Call(&resp, "service_echo", "hello", 10, &Args{"world"}); err != nil { + if err := client.Call(&resp, "test_echo", "hello", 10, &Args{"world"}); err != nil { t.Fatal(err) } if !reflect.DeepEqual(resp, Result{"hello", 10, &Args{"world"}}) { @@ -50,19 +50,19 @@ func TestClientRequest(t *testing.T) { } func TestClientBatchRequest(t *testing.T) { - server := newTestServer("service", new(Service)) + server := newTestServer() defer server.Stop() client := DialInProc(server) defer client.Close() batch := []BatchElem{ { - Method: "service_echo", + Method: "test_echo", Args: []interface{}{"hello", 10, &Args{"world"}}, Result: new(Result), }, { - Method: "service_echo", + Method: "test_echo", Args: []interface{}{"hello2", 11, &Args{"world"}}, Result: new(Result), }, @@ -77,12 +77,12 @@ func TestClientBatchRequest(t *testing.T) { } wantResult := []BatchElem{ { - Method: "service_echo", + Method: "test_echo", Args: []interface{}{"hello", 10, &Args{"world"}}, Result: &Result{"hello", 10, &Args{"world"}}, }, { - Method: "service_echo", + Method: "test_echo", Args: []interface{}{"hello2", 11, &Args{"world"}}, Result: &Result{"hello2", 11, &Args{"world"}}, }, @@ -90,7 +90,7 @@ func TestClientBatchRequest(t *testing.T) { Method: "no_such_method", Args: []interface{}{1, 2, 3}, Result: new(int), - Error: &jsonError{Code: -32601, Message: "The method no_such_method_ does not exist/is not available"}, + Error: &jsonError{Code: -32601, Message: "the method no_such_method does not exist/is not available"}, }, } if !reflect.DeepEqual(batch, wantResult) { @@ -98,6 +98,17 @@ func TestClientBatchRequest(t *testing.T) { } } +func TestClientNotify(t *testing.T) { + server := newTestServer() + defer server.Stop() + client := DialInProc(server) + defer client.Close() + + if err := client.Notify(context.Background(), "test_echo", "hello", 10, &Args{"world"}); err != nil { + t.Fatal(err) + } +} + // func TestClientCancelInproc(t *testing.T) { testClientCancel("inproc", t) } func TestClientCancelWebsocket(t *testing.T) { testClientCancel("ws", t) } func TestClientCancelHTTP(t *testing.T) { testClientCancel("http", t) } @@ -106,7 +117,12 @@ func TestClientCancelIPC(t *testing.T) { testClientCancel("ipc", t) } // This test checks that requests made through CallContext can be canceled by canceling // the context. func testClientCancel(transport string, t *testing.T) { - server := newTestServer("service", new(Service)) + // These tests take a lot of time, run them all at once. + // You probably want to run with -parallel 1 or comment out + // the call to t.Parallel if you enable the logging. + t.Parallel() + + server := newTestServer() defer server.Stop() // What we want to achieve is that the context gets canceled @@ -142,11 +158,6 @@ func testClientCancel(transport string, t *testing.T) { panic("unknown transport: " + transport) } - // These tests take a lot of time, run them all at once. - // You probably want to run with -parallel 1 or comment out - // the call to t.Parallel if you enable the logging. - t.Parallel() - // The actual test starts here. var ( wg sync.WaitGroup @@ -174,7 +185,8 @@ func testClientCancel(transport string, t *testing.T) { } // Now perform a call with the context. // The key thing here is that no call will ever complete successfully. - err := client.CallContext(ctx, nil, "service_sleep", 2*maxContextCancelTimeout) + sleepTime := maxContextCancelTimeout + 20*time.Millisecond + err := client.CallContext(ctx, nil, "test_sleep", sleepTime) if err != nil { log.Debug(fmt.Sprint("got expected error:", err)) } else { @@ -191,7 +203,7 @@ func testClientCancel(transport string, t *testing.T) { } func TestClientSubscribeInvalidArg(t *testing.T) { - server := newTestServer("service", new(Service)) + server := newTestServer() defer server.Stop() client := DialInProc(server) defer client.Close() @@ -221,46 +233,14 @@ func TestClientSubscribeInvalidArg(t *testing.T) { } func TestClientSubscribe(t *testing.T) { - server := newTestServer("eth", new(NotificationTestService)) - defer server.Stop() - client := DialInProc(server) - defer client.Close() - - nc := make(chan int) - count := 10 - sub, err := client.EthSubscribe(context.Background(), nc, "someSubscription", count, 0) - if err != nil { - t.Fatal("can't subscribe:", err) - } - for i := 0; i < count; i++ { - if val := <-nc; val != i { - t.Fatalf("value mismatch: got %d, want %d", val, i) - } - } - - sub.Unsubscribe() - select { - case v := <-nc: - t.Fatal("received value after unsubscribe:", v) - case err := <-sub.Err(): - if err != nil { - t.Fatalf("Err returned a non-nil error after explicit unsubscribe: %q", err) - } - case <-time.After(1 * time.Second): - t.Fatalf("subscription not closed within 1s after unsubscribe") - } -} - -func TestClientSubscribeCustomNamespace(t *testing.T) { - namespace := "custom" - server := newTestServer(namespace, new(NotificationTestService)) + server := newTestServer() defer server.Stop() client := DialInProc(server) defer client.Close() nc := make(chan int) count := 10 - sub, err := client.Subscribe(context.Background(), namespace, nc, "someSubscription", count, 0) + sub, err := client.Subscribe(context.Background(), "nftest", nc, "someSubscription", count, 0) if err != nil { t.Fatal("can't subscribe:", err) } @@ -283,14 +263,17 @@ func TestClientSubscribeCustomNamespace(t *testing.T) { } } -// In this test, the connection drops while EthSubscribe is -// waiting for a response. +// In this test, the connection drops while Subscribe is waiting for a response. func TestClientSubscribeClose(t *testing.T) { - service := &NotificationTestService{ + server := newTestServer() + service := ¬ificationTestService{ gotHangSubscriptionReq: make(chan struct{}), unblockHangSubscription: make(chan struct{}), } - server := newTestServer("eth", service) + if err := server.RegisterName("nftest2", service); err != nil { + t.Fatal(err) + } + defer server.Stop() client := DialInProc(server) defer client.Close() @@ -302,7 +285,7 @@ func TestClientSubscribeClose(t *testing.T) { err error ) go func() { - sub, err = client.EthSubscribe(context.Background(), nc, "hangSubscription", 999) + sub, err = client.Subscribe(context.Background(), "nftest2", nc, "hangSubscription", 999) errc <- err }() @@ -313,27 +296,26 @@ func TestClientSubscribeClose(t *testing.T) { select { case err := <-errc: if err == nil { - t.Errorf("EthSubscribe returned nil error after Close") + t.Errorf("Subscribe returned nil error after Close") } if sub != nil { - t.Error("EthSubscribe returned non-nil subscription after Close") + t.Error("Subscribe returned non-nil subscription after Close") } case <-time.After(1 * time.Second): - t.Fatalf("EthSubscribe did not return within 1s after Close") + t.Fatalf("Subscribe did not return within 1s after Close") } } // This test reproduces https://github.com/ethereum/go-ethereum/issues/17837 where the // client hangs during shutdown when Unsubscribe races with Client.Close. func TestClientCloseUnsubscribeRace(t *testing.T) { - service := &NotificationTestService{} - server := newTestServer("eth", service) + server := newTestServer() defer server.Stop() for i := 0; i < 20; i++ { client := DialInProc(server) nc := make(chan int) - sub, err := client.EthSubscribe(context.Background(), nc, "someSubscription", 3, 1) + sub, err := client.Subscribe(context.Background(), "nftest", nc, "someSubscription", 3, 1) if err != nil { t.Fatal(err) } @@ -350,7 +332,7 @@ func TestClientCloseUnsubscribeRace(t *testing.T) { // This test checks that Client doesn't lock up when a single subscriber // doesn't read subscription events. func TestClientNotificationStorm(t *testing.T) { - server := newTestServer("eth", new(NotificationTestService)) + server := newTestServer() defer server.Stop() doTest := func(count int, wantError bool) { @@ -362,7 +344,7 @@ func TestClientNotificationStorm(t *testing.T) { // Subscribe on the server. It will start sending many notifications // very quickly. nc := make(chan int) - sub, err := client.EthSubscribe(ctx, nc, "someSubscription", count, 0) + sub, err := client.Subscribe(ctx, "nftest", nc, "someSubscription", count, 0) if err != nil { t.Fatal("can't subscribe:", err) } @@ -384,7 +366,7 @@ func TestClientNotificationStorm(t *testing.T) { return } var r int - err := client.CallContext(ctx, &r, "eth_echo", i) + err := client.CallContext(ctx, &r, "nftest_echo", i) if err != nil { if !wantError { t.Fatalf("(%d/%d) call error: %v", i, count, err) @@ -399,7 +381,7 @@ func TestClientNotificationStorm(t *testing.T) { } func TestClientHTTP(t *testing.T) { - server := newTestServer("service", new(Service)) + server := newTestServer() defer server.Stop() client, hs := httpTestClient(server, "http", nil) @@ -416,7 +398,7 @@ func TestClientHTTP(t *testing.T) { for i := range results { i := i go func() { - errc <- client.Call(&results[i], "service_echo", + errc <- client.Call(&results[i], "test_echo", wantResult.String, wantResult.Int, wantResult.Args) }() } @@ -445,16 +427,16 @@ func TestClientHTTP(t *testing.T) { func TestClientReconnect(t *testing.T) { startServer := func(addr string) (*Server, net.Listener) { - srv := newTestServer("service", new(Service)) + srv := newTestServer() l, err := net.Listen("tcp", addr) if err != nil { - t.Fatal(err) + t.Fatal("can't listen:", err) } go http.Serve(l, srv.WebsocketHandler([]string{"*"})) return srv, l } - ctx, cancel := context.WithTimeout(context.Background(), 10*time.Second) + ctx, cancel := context.WithTimeout(context.Background(), 12*time.Second) defer cancel() // Start a server and corresponding client. @@ -466,21 +448,22 @@ func TestClientReconnect(t *testing.T) { // Perform a call. This should work because the server is up. var resp Result - if err := client.CallContext(ctx, &resp, "service_echo", "", 1, nil); err != nil { + if err := client.CallContext(ctx, &resp, "test_echo", "", 1, nil); err != nil { t.Fatal(err) } - // Shut down the server and try calling again. It shouldn't work. + // Shut down the server and allow for some cool down time so we can listen on the same + // address again. l1.Close() s1.Stop() - if err := client.CallContext(ctx, &resp, "service_echo", "", 2, nil); err == nil { + time.Sleep(2 * time.Second) + + // Try calling again. It shouldn't work. + if err := client.CallContext(ctx, &resp, "test_echo", "", 2, nil); err == nil { t.Error("successful call while the server is down") t.Logf("resp: %#v", resp) } - // Allow for some cool down time so we can listen on the same address again. - time.Sleep(2 * time.Second) - // Start it up again and call again. The connection should be reestablished. // We spawn multiple calls here to check whether this hangs somehow. s2, l2 := startServer(l1.Addr().String()) @@ -493,7 +476,7 @@ func TestClientReconnect(t *testing.T) { go func() { <-start var resp Result - errors <- client.CallContext(ctx, &resp, "service_echo", "", 3, nil) + errors <- client.CallContext(ctx, &resp, "test_echo", "", 3, nil) }() } close(start) @@ -503,20 +486,12 @@ func TestClientReconnect(t *testing.T) { errcount++ } } - t.Log("err:", err) + t.Logf("%d errors, last error: %v", errcount, err) if errcount > 1 { t.Errorf("expected one error after disconnect, got %d", errcount) } } -func newTestServer(serviceName string, service interface{}) *Server { - server := NewServer() - if err := server.RegisterName(serviceName, service); err != nil { - panic(err) - } - return server -} - func httpTestClient(srv *Server, transport string, fl *flakeyListener) (*Client, *httptest.Server) { // Create the HTTP server. var hs *httptest.Server diff --git a/rpc/doc.go b/rpc/doc.go index c60381b5ae..e5840c32d3 100644 --- a/rpc/doc.go +++ b/rpc/doc.go @@ -15,43 +15,49 @@ // along with the go-ethereum library. If not, see . /* -Package rpc provides access to the exported methods of an object across a network -or other I/O connection. After creating a server instance objects can be registered, -making it visible from the outside. Exported methods that follow specific -conventions can be called remotely. It also has support for the publish/subscribe -pattern. + +Package rpc implements bi-directional JSON-RPC 2.0 on multiple transports. + +It provides access to the exported methods of an object across a network or other I/O +connection. After creating a server or client instance, objects can be registered to make +them visible as 'services'. Exported methods that follow specific conventions can be +called remotely. It also has support for the publish/subscribe pattern. + +RPC Methods Methods that satisfy the following criteria are made available for remote access: - - object must be exported + - method must be exported - method returns 0, 1 (response or error) or 2 (response and error) values - method argument(s) must be exported or builtin types - method returned value(s) must be exported or builtin types An example method: + func (s *CalcService) Add(a, b int) (int, error) -When the returned error isn't nil the returned integer is ignored and the error is -sent back to the client. Otherwise the returned integer is sent back to the client. +When the returned error isn't nil the returned integer is ignored and the error is sent +back to the client. Otherwise the returned integer is sent back to the client. -Optional arguments are supported by accepting pointer values as arguments. E.g. -if we want to do the addition in an optional finite field we can accept a mod -argument as pointer value. +Optional arguments are supported by accepting pointer values as arguments. E.g. if we want +to do the addition in an optional finite field we can accept a mod argument as pointer +value. - func (s *CalService) Add(a, b int, mod *int) (int, error) + func (s *CalcService) Add(a, b int, mod *int) (int, error) -This RPC method can be called with 2 integers and a null value as third argument. -In that case the mod argument will be nil. Or it can be called with 3 integers, -in that case mod will be pointing to the given third argument. Since the optional -argument is the last argument the RPC package will also accept 2 integers as -arguments. It will pass the mod argument as nil to the RPC method. +This RPC method can be called with 2 integers and a null value as third argument. In that +case the mod argument will be nil. Or it can be called with 3 integers, in that case mod +will be pointing to the given third argument. Since the optional argument is the last +argument the RPC package will also accept 2 integers as arguments. It will pass the mod +argument as nil to the RPC method. -The server offers the ServeCodec method which accepts a ServerCodec instance. It will -read requests from the codec, process the request and sends the response back to the -client using the codec. The server can execute requests concurrently. Responses -can be sent back to the client out of order. +The server offers the ServeCodec method which accepts a ServerCodec instance. It will read +requests from the codec, process the request and sends the response back to the client +using the codec. The server can execute requests concurrently. Responses can be sent back +to the client out of order. An example server which uses the JSON codec: + type CalculatorService struct {} func (s *CalculatorService) Add(a, b int) int { @@ -73,26 +79,40 @@ An example server which uses the JSON codec: for { c, _ := l.AcceptUnix() codec := v2.NewJSONCodec(c) - go server.ServeCodec(codec) + go server.ServeCodec(codec, 0) } +Subscriptions + The package also supports the publish subscribe pattern through the use of subscriptions. -A method that is considered eligible for notifications must satisfy the following criteria: - - object must be exported +A method that is considered eligible for notifications must satisfy the following +criteria: + - method must be exported - first method argument type must be context.Context - method argument(s) must be exported or builtin types - - method must return the tuple Subscription, error + - method must have return types (rpc.Subscription, error) An example method: - func (s *BlockChainService) NewBlocks(ctx context.Context) (Subscription, error) { + + func (s *BlockChainService) NewBlocks(ctx context.Context) (rpc.Subscription, error) { ... } -Subscriptions are deleted when: - - the user sends an unsubscribe request - - the connection which was used to create the subscription is closed. This can be initiated - by the client and server. The server will close the connection on a write error or when - the queue of buffered notifications gets too big. +When the service containing the subscription method is registered to the server, for +example under the "blockchain" namespace, a subscription is created by calling the +"blockchain_subscribe" method. + +Subscriptions are deleted when the user sends an unsubscribe request or when the +connection which was used to create the subscription is closed. This can be initiated by +the client and server. The server will close the connection for any write error. + +For more information about subscriptions, see https://github.com/ethereum/go-ethereum/wiki/RPC-PUB-SUB. + +Reverse Calls + +In any method handler, an instance of rpc.Client can be accessed through the +ClientFromContext method. Using this client instance, server-to-client method calls can be +performed on the RPC connection. */ package rpc diff --git a/rpc/errors.go b/rpc/errors.go index 9cf9dc60c2..c3aa826cc8 100644 --- a/rpc/errors.go +++ b/rpc/errors.go @@ -18,18 +18,31 @@ package rpc import "fmt" -// request is for an unknown service -type methodNotFoundError struct { - service string - method string -} +const defaultErrorCode = -32000 + +type methodNotFoundError struct{ method string } func (e *methodNotFoundError) ErrorCode() int { return -32601 } func (e *methodNotFoundError) Error() string { - return fmt.Sprintf("The method %s%s%s does not exist/is not available", e.service, serviceMethodSeparator, e.method) + return fmt.Sprintf("the method %s does not exist/is not available", e.method) +} + +type subscriptionNotFoundError struct{ namespace, subscription string } + +func (e *subscriptionNotFoundError) ErrorCode() int { return -32601 } + +func (e *subscriptionNotFoundError) Error() string { + return fmt.Sprintf("no %q subscription in %s namespace", e.subscription, e.namespace) } +// Invalid JSON was received by the server. +type parseError struct{ message string } + +func (e *parseError) ErrorCode() int { return -32700 } + +func (e *parseError) Error() string { return e.message } + // received message isn't a valid request type invalidRequestError struct{ message string } @@ -50,17 +63,3 @@ type invalidParamsError struct{ message string } func (e *invalidParamsError) ErrorCode() int { return -32602 } func (e *invalidParamsError) Error() string { return e.message } - -// logic error, callback returned an error -type callbackError struct{ message string } - -func (e *callbackError) ErrorCode() int { return -32000 } - -func (e *callbackError) Error() string { return e.message } - -// issued when a request is received after the server is issued to stop. -type shutdownError struct{} - -func (e *shutdownError) ErrorCode() int { return -32000 } - -func (e *shutdownError) Error() string { return "server is shutting down" } diff --git a/rpc/handler.go b/rpc/handler.go new file mode 100644 index 0000000000..bc03ef25f4 --- /dev/null +++ b/rpc/handler.go @@ -0,0 +1,397 @@ +// Copyright 2018 The go-ethereum Authors +// This file is part of the go-ethereum library. +// +// The go-ethereum library is free software: you can redistribute it and/or modify +// it under the terms of the GNU Lesser General Public License as published by +// the Free Software Foundation, either version 3 of the License, or +// (at your option) any later version. +// +// The go-ethereum library is distributed in the hope that it will be useful, +// but WITHOUT ANY WARRANTY; without even the implied warranty of +// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the +// GNU Lesser General Public License for more details. +// +// You should have received a copy of the GNU Lesser General Public License +// along with the go-ethereum library. If not, see . + +package rpc + +import ( + "context" + "encoding/json" + "reflect" + "strconv" + "strings" + "sync" + "time" + + "github.com/ethereum/go-ethereum/log" +) + +// handler handles JSON-RPC messages. There is one handler per connection. Note that +// handler is not safe for concurrent use. Message handling never blocks indefinitely +// because RPCs are processed on background goroutines launched by handler. +// +// The entry points for incoming messages are: +// +// h.handleMsg(message) +// h.handleBatch(message) +// +// Outgoing calls use the requestOp struct. Register the request before sending it +// on the connection: +// +// op := &requestOp{ids: ...} +// h.addRequestOp(op) +// +// Now send the request, then wait for the reply to be delivered through handleMsg: +// +// if err := op.wait(...); err != nil { +// h.removeRequestOp(op) // timeout, etc. +// } +// +type handler struct { + reg *serviceRegistry + unsubscribeCb *callback + idgen func() ID // subscription ID generator + respWait map[string]*requestOp // active client requests + clientSubs map[string]*ClientSubscription // active client subscriptions + callWG sync.WaitGroup // pending call goroutines + rootCtx context.Context // canceled by close() + cancelRoot func() // cancel function for rootCtx + conn jsonWriter // where responses will be sent + log log.Logger + allowSubscribe bool + + subLock sync.Mutex + serverSubs map[ID]*Subscription +} + +type callProc struct { + ctx context.Context + notifiers []*Notifier +} + +func newHandler(connCtx context.Context, conn jsonWriter, idgen func() ID, reg *serviceRegistry) *handler { + rootCtx, cancelRoot := context.WithCancel(connCtx) + h := &handler{ + reg: reg, + idgen: idgen, + conn: conn, + respWait: make(map[string]*requestOp), + clientSubs: make(map[string]*ClientSubscription), + rootCtx: rootCtx, + cancelRoot: cancelRoot, + allowSubscribe: true, + serverSubs: make(map[ID]*Subscription), + log: log.Root(), + } + if conn.RemoteAddr() != "" { + h.log = h.log.New("conn", conn.RemoteAddr()) + } + h.unsubscribeCb = newCallback(reflect.Value{}, reflect.ValueOf(h.unsubscribe)) + return h +} + +// handleBatch executes all messages in a batch and returns the responses. +func (h *handler) handleBatch(msgs []*jsonrpcMessage) { + // Emit error response for empty batches: + if len(msgs) == 0 { + h.startCallProc(func(cp *callProc) { + h.conn.Write(cp.ctx, errorMessage(&invalidRequestError{"empty batch"})) + }) + return + } + + // Handle non-call messages first: + calls := make([]*jsonrpcMessage, 0, len(msgs)) + for _, msg := range msgs { + if handled := h.handleImmediate(msg); !handled { + calls = append(calls, msg) + } + } + if len(calls) == 0 { + return + } + // Process calls on a goroutine because they may block indefinitely: + h.startCallProc(func(cp *callProc) { + answers := make([]*jsonrpcMessage, 0, len(msgs)) + for _, msg := range calls { + if answer := h.handleCallMsg(cp, msg); answer != nil { + answers = append(answers, answer) + } + } + h.addSubscriptions(cp.notifiers) + if len(answers) > 0 { + h.conn.Write(cp.ctx, answers) + } + for _, n := range cp.notifiers { + n.activate() + } + }) +} + +// handleMsg handles a single message. +func (h *handler) handleMsg(msg *jsonrpcMessage) { + if ok := h.handleImmediate(msg); ok { + return + } + h.startCallProc(func(cp *callProc) { + answer := h.handleCallMsg(cp, msg) + h.addSubscriptions(cp.notifiers) + if answer != nil { + h.conn.Write(cp.ctx, answer) + } + for _, n := range cp.notifiers { + n.activate() + } + }) +} + +// close cancels all requests except for inflightReq and waits for +// call goroutines to shut down. +func (h *handler) close(err error, inflightReq *requestOp) { + h.cancelAllRequests(err, inflightReq) + h.cancelRoot() + h.callWG.Wait() + h.cancelServerSubscriptions(err) +} + +// addRequestOp registers a request operation. +func (h *handler) addRequestOp(op *requestOp) { + for _, id := range op.ids { + h.respWait[string(id)] = op + } +} + +// removeRequestOps stops waiting for the given request IDs. +func (h *handler) removeRequestOp(op *requestOp) { + for _, id := range op.ids { + delete(h.respWait, string(id)) + } +} + +// cancelAllRequests unblocks and removes pending requests and active subscriptions. +func (h *handler) cancelAllRequests(err error, inflightReq *requestOp) { + didClose := make(map[*requestOp]bool) + if inflightReq != nil { + didClose[inflightReq] = true + } + + for id, op := range h.respWait { + // Remove the op so that later calls will not close op.resp again. + delete(h.respWait, id) + + if !didClose[op] { + op.err = err + close(op.resp) + didClose[op] = true + } + } + for id, sub := range h.clientSubs { + delete(h.clientSubs, id) + sub.quitWithError(err, false) + } +} + +func (h *handler) addSubscriptions(nn []*Notifier) { + h.subLock.Lock() + defer h.subLock.Unlock() + + for _, n := range nn { + if sub := n.takeSubscription(); sub != nil { + h.serverSubs[sub.ID] = sub + } + } +} + +// cancelServerSubscriptions removes all subscriptions and closes their error channels. +func (h *handler) cancelServerSubscriptions(err error) { + h.subLock.Lock() + defer h.subLock.Unlock() + + for id, s := range h.serverSubs { + s.err <- err + close(s.err) + delete(h.serverSubs, id) + } +} + +// startCallProc runs fn in a new goroutine and starts tracking it in the h.calls wait group. +func (h *handler) startCallProc(fn func(*callProc)) { + h.callWG.Add(1) + go func() { + ctx, cancel := context.WithCancel(h.rootCtx) + defer h.callWG.Done() + defer cancel() + fn(&callProc{ctx: ctx}) + }() +} + +// handleImmediate executes non-call messages. It returns false if the message is a +// call or requires a reply. +func (h *handler) handleImmediate(msg *jsonrpcMessage) bool { + start := time.Now() + switch { + case msg.isNotification(): + if strings.HasSuffix(msg.Method, notificationMethodSuffix) { + h.handleSubscriptionResult(msg) + return true + } + return false + case msg.isResponse(): + h.handleResponse(msg) + h.log.Trace("Handled RPC response", "reqid", idForLog{msg.ID}, "t", time.Since(start)) + return true + default: + return false + } +} + +// handleSubscriptionResult processes subscription notifications. +func (h *handler) handleSubscriptionResult(msg *jsonrpcMessage) { + var result subscriptionResult + if err := json.Unmarshal(msg.Params, &result); err != nil { + h.log.Debug("Dropping invalid subscription message") + return + } + if h.clientSubs[result.ID] != nil { + h.clientSubs[result.ID].deliver(result.Result) + } +} + +// handleResponse processes method call responses. +func (h *handler) handleResponse(msg *jsonrpcMessage) { + op := h.respWait[string(msg.ID)] + if op == nil { + h.log.Debug("Unsolicited RPC response", "reqid", idForLog{msg.ID}) + return + } + delete(h.respWait, string(msg.ID)) + // For normal responses, just forward the reply to Call/BatchCall. + if op.sub == nil { + op.resp <- msg + return + } + // For subscription responses, start the subscription if the server + // indicates success. EthSubscribe gets unblocked in either case through + // the op.resp channel. + defer close(op.resp) + if msg.Error != nil { + op.err = msg.Error + return + } + if op.err = json.Unmarshal(msg.Result, &op.sub.subid); op.err == nil { + go op.sub.start() + h.clientSubs[op.sub.subid] = op.sub + } +} + +// handleCallMsg executes a call message and returns the answer. +func (h *handler) handleCallMsg(ctx *callProc, msg *jsonrpcMessage) *jsonrpcMessage { + start := time.Now() + switch { + case msg.isNotification(): + h.handleCall(ctx, msg) + h.log.Debug("Served "+msg.Method, "t", time.Since(start)) + return nil + case msg.isCall(): + resp := h.handleCall(ctx, msg) + if resp.Error != nil { + h.log.Info("Served "+msg.Method, "reqid", idForLog{msg.ID}, "t", time.Since(start), "err", resp.Error.Message) + } else { + h.log.Debug("Served "+msg.Method, "reqid", idForLog{msg.ID}, "t", time.Since(start)) + } + return resp + case msg.hasValidID(): + return msg.errorResponse(&invalidRequestError{"invalid request"}) + default: + return errorMessage(&invalidRequestError{"invalid request"}) + } +} + +// handleCall processes method calls. +func (h *handler) handleCall(cp *callProc, msg *jsonrpcMessage) *jsonrpcMessage { + if msg.isSubscribe() { + return h.handleSubscribe(cp, msg) + } + var callb *callback + if msg.isUnsubscribe() { + callb = h.unsubscribeCb + } else { + callb = h.reg.callback(msg.Method) + } + if callb == nil { + return msg.errorResponse(&methodNotFoundError{method: msg.Method}) + } + args, err := parsePositionalArguments(msg.Params, callb.argTypes) + if err != nil { + return msg.errorResponse(&invalidParamsError{err.Error()}) + } + + return h.runMethod(cp.ctx, msg, callb, args) +} + +// handleSubscribe processes *_subscribe method calls. +func (h *handler) handleSubscribe(cp *callProc, msg *jsonrpcMessage) *jsonrpcMessage { + if !h.allowSubscribe { + return msg.errorResponse(ErrNotificationsUnsupported) + } + + // Subscription method name is first argument. + name, err := parseSubscriptionName(msg.Params) + if err != nil { + return msg.errorResponse(&invalidParamsError{err.Error()}) + } + namespace := msg.namespace() + callb := h.reg.subscription(namespace, name) + if callb == nil { + return msg.errorResponse(&subscriptionNotFoundError{namespace, name}) + } + + // Parse subscription name arg too, but remove it before calling the callback. + argTypes := append([]reflect.Type{stringType}, callb.argTypes...) + args, err := parsePositionalArguments(msg.Params, argTypes) + if err != nil { + return msg.errorResponse(&invalidParamsError{err.Error()}) + } + args = args[1:] + + // Install notifier in context so the subscription handler can find it. + n := &Notifier{h: h, namespace: namespace} + cp.notifiers = append(cp.notifiers, n) + ctx := context.WithValue(cp.ctx, notifierKey{}, n) + + return h.runMethod(ctx, msg, callb, args) +} + +// runMethod runs the Go callback for an RPC method. +func (h *handler) runMethod(ctx context.Context, msg *jsonrpcMessage, callb *callback, args []reflect.Value) *jsonrpcMessage { + result, err := callb.call(ctx, msg.Method, args) + if err != nil { + return msg.errorResponse(err) + } + return msg.response(result) +} + +// unsubscribe is the callback function for all *_unsubscribe calls. +func (h *handler) unsubscribe(ctx context.Context, id ID) (bool, error) { + h.subLock.Lock() + defer h.subLock.Unlock() + + s := h.serverSubs[id] + if s == nil { + return false, ErrSubscriptionNotFound + } + close(s.err) + delete(h.serverSubs, id) + return true, nil +} + +type idForLog struct{ json.RawMessage } + +func (id idForLog) String() string { + if s, err := strconv.Unquote(string(id.RawMessage)); err == nil { + return s + } + return string(id.RawMessage) +} diff --git a/rpc/http.go b/rpc/http.go index 59dd5eebc6..518b3b874f 100644 --- a/rpc/http.go +++ b/rpc/http.go @@ -37,38 +37,39 @@ import ( const ( maxRequestContentLength = 1024 * 512 + contentType = "application/json" ) -var ( - // https://www.jsonrpc.org/historical/json-rpc-over-http.html#id13 - acceptedContentTypes = []string{"application/json", "application/json-rpc", "application/jsonrequest"} - contentType = acceptedContentTypes[0] - nullAddr, _ = net.ResolveTCPAddr("tcp", "127.0.0.1:0") -) +// https://www.jsonrpc.org/historical/json-rpc-over-http.html#id13 +var acceptedContentTypes = []string{contentType, "application/json-rpc", "application/jsonrequest"} type httpConn struct { client *http.Client req *http.Request closeOnce sync.Once - closed chan struct{} + closed chan interface{} } // httpConn is treated specially by Client. -func (hc *httpConn) LocalAddr() net.Addr { return nullAddr } -func (hc *httpConn) RemoteAddr() net.Addr { return nullAddr } -func (hc *httpConn) SetReadDeadline(time.Time) error { return nil } -func (hc *httpConn) SetWriteDeadline(time.Time) error { return nil } -func (hc *httpConn) SetDeadline(time.Time) error { return nil } -func (hc *httpConn) Write([]byte) (int, error) { panic("Write called") } - -func (hc *httpConn) Read(b []byte) (int, error) { +func (hc *httpConn) Write(context.Context, interface{}) error { + panic("Write called on httpConn") +} + +func (hc *httpConn) RemoteAddr() string { + return hc.req.URL.String() +} + +func (hc *httpConn) Read() ([]*jsonrpcMessage, bool, error) { <-hc.closed - return 0, io.EOF + return nil, false, io.EOF } -func (hc *httpConn) Close() error { +func (hc *httpConn) Close() { hc.closeOnce.Do(func() { close(hc.closed) }) - return nil +} + +func (hc *httpConn) Closed() <-chan interface{} { + return hc.closed } // HTTPTimeouts represents the configuration params for the HTTP RPC server. @@ -114,8 +115,8 @@ func DialHTTPWithClient(endpoint string, client *http.Client) (*Client, error) { req.Header.Set("Accept", contentType) initctx := context.Background() - return newClient(initctx, func(context.Context) (net.Conn, error) { - return &httpConn{client: client, req: req, closed: make(chan struct{})}, nil + return newClient(initctx, func(context.Context) (ServerCodec, error) { + return &httpConn{client: client, req: req, closed: make(chan interface{})}, nil }) } @@ -184,17 +185,30 @@ func (hc *httpConn) doRequest(ctx context.Context, msg interface{}) (io.ReadClos return resp.Body, nil } -// httpReadWriteNopCloser wraps a io.Reader and io.Writer with a NOP Close method. -type httpReadWriteNopCloser struct { +// httpServerConn turns a HTTP connection into a Conn. +type httpServerConn struct { io.Reader io.Writer + r *http.Request } -// Close does nothing and returns always nil -func (t *httpReadWriteNopCloser) Close() error { - return nil +func newHTTPServerConn(r *http.Request, w http.ResponseWriter) ServerCodec { + body := io.LimitReader(r.Body, maxRequestContentLength) + conn := &httpServerConn{Reader: body, Writer: w, r: r} + return NewJSONCodec(conn) } +// Close does nothing and always returns nil. +func (t *httpServerConn) Close() error { return nil } + +// RemoteAddr returns the peer address of the underlying connection. +func (t *httpServerConn) RemoteAddr() string { + return t.r.RemoteAddr +} + +// SetWriteDeadline does nothing and always returns nil. +func (t *httpServerConn) SetWriteDeadline(time.Time) error { return nil } + // NewHTTPServer creates a new HTTP RPC server around an API provider. // // Deprecated: Server implements http.Handler @@ -226,7 +240,7 @@ func NewHTTPServer(cors []string, vhosts []string, timeouts HTTPTimeouts, srv ht } // ServeHTTP serves JSON-RPC requests over HTTP. -func (srv *Server) ServeHTTP(w http.ResponseWriter, r *http.Request) { +func (s *Server) ServeHTTP(w http.ResponseWriter, r *http.Request) { // Permit dumb empty requests for remote health-checks (AWS) if r.Method == http.MethodGet && r.ContentLength == 0 && r.URL.RawQuery == "" { return @@ -249,12 +263,10 @@ func (srv *Server) ServeHTTP(w http.ResponseWriter, r *http.Request) { ctx = context.WithValue(ctx, "Origin", origin) } - body := io.LimitReader(r.Body, maxRequestContentLength) - codec := NewJSONCodec(&httpReadWriteNopCloser{body, w}) - defer codec.Close() - w.Header().Set("content-type", contentType) - srv.ServeSingleRequest(ctx, codec, OptionMethodInvocation) + codec := newHTTPServerConn(r, w) + defer codec.Close() + s.serveSingleRequest(ctx, codec) } // validateRequest returns a non-zero response code and error message if the diff --git a/rpc/inproc.go b/rpc/inproc.go index cbe65d10e7..c4456cfc4b 100644 --- a/rpc/inproc.go +++ b/rpc/inproc.go @@ -24,10 +24,10 @@ import ( // DialInProc attaches an in-process connection to the given RPC server. func DialInProc(handler *Server) *Client { initctx := context.Background() - c, _ := newClient(initctx, func(context.Context) (net.Conn, error) { + c, _ := newClient(initctx, func(context.Context) (ServerCodec, error) { p1, p2 := net.Pipe() go handler.ServeCodec(NewJSONCodec(p1), OptionMethodInvocation|OptionSubscriptions) - return p2, nil + return NewJSONCodec(p2), nil }) return c } diff --git a/rpc/ipc.go b/rpc/ipc.go index 4cce1cf74b..ad8ce03098 100644 --- a/rpc/ipc.go +++ b/rpc/ipc.go @@ -25,17 +25,17 @@ import ( ) // ServeListener accepts connections on l, serving JSON-RPC on them. -func (srv *Server) ServeListener(l net.Listener) error { +func (s *Server) ServeListener(l net.Listener) error { for { conn, err := l.Accept() if netutil.IsTemporaryError(err) { - log.Warn("IPC accept error", "err", err) + log.Warn("RPC accept error", "err", err) continue } else if err != nil { return err } - log.Trace("IPC accepted connection") - go srv.ServeCodec(NewJSONCodec(conn), OptionMethodInvocation|OptionSubscriptions) + log.Trace("Accepted RPC connection", "conn", conn.RemoteAddr()) + go s.ServeCodec(NewJSONCodec(conn), OptionMethodInvocation|OptionSubscriptions) } } @@ -46,7 +46,11 @@ func (srv *Server) ServeListener(l net.Listener) error { // The context is used for the initial connection establishment. It does not // affect subsequent interactions with the client. func DialIPC(ctx context.Context, endpoint string) (*Client, error) { - return newClient(ctx, func(ctx context.Context) (net.Conn, error) { - return newIPCConnection(ctx, endpoint) + return newClient(ctx, func(ctx context.Context) (ServerCodec, error) { + conn, err := newIPCConnection(ctx, endpoint) + if err != nil { + return nil, err + } + return NewJSONCodec(conn), err }) } diff --git a/rpc/json.go b/rpc/json.go index a523eeb8ef..b2e8c7bab3 100644 --- a/rpc/json.go +++ b/rpc/json.go @@ -18,71 +18,110 @@ package rpc import ( "bytes" + "context" "encoding/json" + "errors" "fmt" "io" "reflect" - "strconv" "strings" "sync" - - "github.com/ethereum/go-ethereum/log" + "time" ) const ( - jsonrpcVersion = "2.0" + vsn = "2.0" serviceMethodSeparator = "_" subscribeMethodSuffix = "_subscribe" unsubscribeMethodSuffix = "_unsubscribe" notificationMethodSuffix = "_subscription" + + defaultWriteTimeout = 10 * time.Second // used if context has no deadline ) -type jsonRequest struct { - Method string `json:"method"` - Version string `json:"jsonrpc"` - Id json.RawMessage `json:"id,omitempty"` - Payload json.RawMessage `json:"params,omitempty"` +var null = json.RawMessage("null") + +type subscriptionResult struct { + ID string `json:"subscription"` + Result json.RawMessage `json:"result,omitempty"` } -type jsonSuccessResponse struct { - Version string `json:"jsonrpc"` - Id interface{} `json:"id,omitempty"` - Result interface{} `json:"result"` +// A value of this type can a JSON-RPC request, notification, successful response or +// error response. Which one it is depends on the fields. +type jsonrpcMessage struct { + Version string `json:"jsonrpc,omitempty"` + ID json.RawMessage `json:"id,omitempty"` + Method string `json:"method,omitempty"` + Params json.RawMessage `json:"params,omitempty"` + Error *jsonError `json:"error,omitempty"` + Result json.RawMessage `json:"result,omitempty"` } -type jsonError struct { - Code int `json:"code"` - Message string `json:"message"` - Data interface{} `json:"data,omitempty"` +func (msg *jsonrpcMessage) isNotification() bool { + return msg.ID == nil && msg.Method != "" } -type jsonErrResponse struct { - Version string `json:"jsonrpc"` - Id interface{} `json:"id,omitempty"` - Error jsonError `json:"error"` +func (msg *jsonrpcMessage) isCall() bool { + return msg.hasValidID() && msg.Method != "" } -type jsonSubscription struct { - Subscription string `json:"subscription"` - Result interface{} `json:"result,omitempty"` +func (msg *jsonrpcMessage) isResponse() bool { + return msg.hasValidID() && msg.Method == "" && msg.Params == nil && (msg.Result != nil || msg.Error != nil) } -type jsonNotification struct { - Version string `json:"jsonrpc"` - Method string `json:"method"` - Params jsonSubscription `json:"params"` +func (msg *jsonrpcMessage) hasValidID() bool { + return len(msg.ID) > 0 && msg.ID[0] != '{' && msg.ID[0] != '[' } -// jsonCodec reads and writes JSON-RPC messages to the underlying connection. It -// also has support for parsing arguments and serializing (result) objects. -type jsonCodec struct { - closer sync.Once // close closed channel once - closed chan interface{} // closed on Close - decMu sync.Mutex // guards the decoder - decode func(v interface{}) error // decoder to allow multiple transports - encMu sync.Mutex // guards the encoder - encode func(v interface{}) error // encoder to allow multiple transports - rw io.ReadWriteCloser // connection +func (msg *jsonrpcMessage) isSubscribe() bool { + return strings.HasSuffix(msg.Method, subscribeMethodSuffix) +} + +func (msg *jsonrpcMessage) isUnsubscribe() bool { + return strings.HasSuffix(msg.Method, unsubscribeMethodSuffix) +} + +func (msg *jsonrpcMessage) namespace() string { + elem := strings.SplitN(msg.Method, serviceMethodSeparator, 2) + return elem[0] +} + +func (msg *jsonrpcMessage) String() string { + b, _ := json.Marshal(msg) + return string(b) +} + +func (msg *jsonrpcMessage) errorResponse(err error) *jsonrpcMessage { + resp := errorMessage(err) + resp.ID = msg.ID + return resp +} + +func (msg *jsonrpcMessage) response(result interface{}) *jsonrpcMessage { + enc, err := json.Marshal(result) + if err != nil { + // TODO: wrap with 'internal server error' + return msg.errorResponse(err) + } + return &jsonrpcMessage{Version: vsn, ID: msg.ID, Result: enc} +} + +func errorMessage(err error) *jsonrpcMessage { + msg := &jsonrpcMessage{Version: vsn, ID: null, Error: &jsonError{ + Code: defaultErrorCode, + Message: err.Error(), + }} + ec, ok := err.(Error) + if ok { + msg.Error.Code = ec.ErrorCode() + } + return msg +} + +type jsonError struct { + Code int `json:"code"` + Message string `json:"message"` + Data interface{} `json:"data,omitempty"` } func (err *jsonError) Error() string { @@ -96,268 +135,196 @@ func (err *jsonError) ErrorCode() int { return err.Code } +// Conn is a subset of the methods of net.Conn which are sufficient for ServerCodec. +type Conn interface { + io.ReadWriteCloser + SetWriteDeadline(time.Time) error +} + +// ConnRemoteAddr wraps the RemoteAddr operation, which returns a description +// of the peer address of a connection. If a Conn also implements ConnRemoteAddr, this +// description is used in log messages. +type ConnRemoteAddr interface { + RemoteAddr() string +} + +// connWithRemoteAddr overrides the remote address of a connection. +type connWithRemoteAddr struct { + Conn + addr string +} + +func (c connWithRemoteAddr) RemoteAddr() string { return c.addr } + +// jsonCodec reads and writes JSON-RPC messages to the underlying connection. It also has +// support for parsing arguments and serializing (result) objects. +type jsonCodec struct { + remoteAddr string + closer sync.Once // close closed channel once + closed chan interface{} // closed on Close + decode func(v interface{}) error // decoder to allow multiple transports + encMu sync.Mutex // guards the encoder + encode func(v interface{}) error // encoder to allow multiple transports + conn Conn +} + // NewCodec creates a new RPC server codec with support for JSON-RPC 2.0 based // on explicitly given encoding and decoding methods. -func NewCodec(rwc io.ReadWriteCloser, encode, decode func(v interface{}) error) ServerCodec { - return &jsonCodec{ +func NewCodec(conn Conn, encode, decode func(v interface{}) error) ServerCodec { + codec := &jsonCodec{ closed: make(chan interface{}), encode: encode, decode: decode, - rw: rwc, + conn: conn, } + if ra, ok := conn.(ConnRemoteAddr); ok { + codec.remoteAddr = ra.RemoteAddr() + } + return codec } // NewJSONCodec creates a new RPC server codec with support for JSON-RPC 2.0. -func NewJSONCodec(rwc io.ReadWriteCloser) ServerCodec { - enc := json.NewEncoder(rwc) - dec := json.NewDecoder(rwc) +func NewJSONCodec(conn Conn) ServerCodec { + enc := json.NewEncoder(conn) + dec := json.NewDecoder(conn) dec.UseNumber() + return NewCodec(conn, enc.Encode, dec.Decode) +} - return &jsonCodec{ - closed: make(chan interface{}), - encode: enc.Encode, - decode: dec.Decode, - rw: rwc, - } +func (c *jsonCodec) RemoteAddr() string { + return c.remoteAddr } -// isBatch returns true when the first non-whitespace characters is '[' -func isBatch(msg json.RawMessage) bool { - for _, c := range msg { - // skip insignificant whitespace (http://www.ietf.org/rfc/rfc4627.txt) - if c == 0x20 || c == 0x09 || c == 0x0a || c == 0x0d { - continue - } - return c == '[' +func (c *jsonCodec) Read() (msg []*jsonrpcMessage, batch bool, err error) { + // Decode the next JSON object in the input stream. + // This verifies basic syntax, etc. + var rawmsg json.RawMessage + if err := c.decode(&rawmsg); err != nil { + return nil, false, err } - return false + msg, batch = parseMessage(rawmsg) + return msg, batch, nil } -// ReadRequestHeaders will read new requests without parsing the arguments. It will -// return a collection of requests, an indication if these requests are in batch -// form or an error when the incoming message could not be read/parsed. -func (c *jsonCodec) ReadRequestHeaders() ([]rpcRequest, bool, Error) { - c.decMu.Lock() - defer c.decMu.Unlock() +// Write sends a message to client. +func (c *jsonCodec) Write(ctx context.Context, v interface{}) error { + c.encMu.Lock() + defer c.encMu.Unlock() - var incomingMsg json.RawMessage - if err := c.decode(&incomingMsg); err != nil { - return nil, false, &invalidRequestError{err.Error()} - } - if isBatch(incomingMsg) { - return parseBatchRequest(incomingMsg) + deadline, ok := ctx.Deadline() + if !ok { + deadline = time.Now().Add(defaultWriteTimeout) } - return parseRequest(incomingMsg) + c.conn.SetWriteDeadline(deadline) + return c.encode(v) } -// checkReqId returns an error when the given reqId isn't valid for RPC method calls. -// valid id's are strings, numbers or null -func checkReqId(reqId json.RawMessage) error { - if len(reqId) == 0 { - return fmt.Errorf("missing request id") - } - if _, err := strconv.ParseFloat(string(reqId), 64); err == nil { - return nil - } - var str string - if err := json.Unmarshal(reqId, &str); err == nil { - return nil - } - return fmt.Errorf("invalid request id") +// Close the underlying connection +func (c *jsonCodec) Close() { + c.closer.Do(func() { + close(c.closed) + c.conn.Close() + }) } -// parseRequest will parse a single request from the given RawMessage. It will return -// the parsed request, an indication if the request was a batch or an error when -// the request could not be parsed. -func parseRequest(incomingMsg json.RawMessage) ([]rpcRequest, bool, Error) { - var in jsonRequest - if err := json.Unmarshal(incomingMsg, &in); err != nil { - return nil, false, &invalidMessageError{err.Error()} - } - - if err := checkReqId(in.Id); err != nil { - return nil, false, &invalidMessageError{err.Error()} - } - - // subscribe are special, they will always use `subscribeMethod` as first param in the payload - if strings.HasSuffix(in.Method, subscribeMethodSuffix) { - reqs := []rpcRequest{{id: &in.Id, isPubSub: true}} - if len(in.Payload) > 0 { - // first param must be subscription name - var subscribeMethod [1]string - if err := json.Unmarshal(in.Payload, &subscribeMethod); err != nil { - log.Debug(fmt.Sprintf("Unable to parse subscription method: %v\n", err)) - return nil, false, &invalidRequestError{"Unable to parse subscription request"} - } - - reqs[0].service, reqs[0].method = strings.TrimSuffix(in.Method, subscribeMethodSuffix), subscribeMethod[0] - reqs[0].params = in.Payload - return reqs, false, nil - } - return nil, false, &invalidRequestError{"Unable to parse subscription request"} - } - - if strings.HasSuffix(in.Method, unsubscribeMethodSuffix) { - return []rpcRequest{{id: &in.Id, isPubSub: true, - method: in.Method, params: in.Payload}}, false, nil - } +// Closed returns a channel which will be closed when Close is called +func (c *jsonCodec) Closed() <-chan interface{} { + return c.closed +} - elems := strings.Split(in.Method, serviceMethodSeparator) - if len(elems) != 2 { - return nil, false, &methodNotFoundError{in.Method, ""} +// parseMessage parses raw bytes as a (batch of) JSON-RPC message(s). There are no error +// checks in this function because the raw message has already been syntax-checked when it +// is called. Any non-JSON-RPC messages in the input return the zero value of +// jsonrpcMessage. +func parseMessage(raw json.RawMessage) ([]*jsonrpcMessage, bool) { + if !isBatch(raw) { + msgs := []*jsonrpcMessage{{}} + json.Unmarshal(raw, &msgs[0]) + return msgs, false } - - // regular RPC call - if len(in.Payload) == 0 { - return []rpcRequest{{service: elems[0], method: elems[1], id: &in.Id}}, false, nil + dec := json.NewDecoder(bytes.NewReader(raw)) + dec.Token() // skip '[' + var msgs []*jsonrpcMessage + for dec.More() { + msgs = append(msgs, new(jsonrpcMessage)) + dec.Decode(&msgs[len(msgs)-1]) } - - return []rpcRequest{{service: elems[0], method: elems[1], id: &in.Id, params: in.Payload}}, false, nil + return msgs, true } -// parseBatchRequest will parse a batch request into a collection of requests from the given RawMessage, an indication -// if the request was a batch or an error when the request could not be read. -func parseBatchRequest(incomingMsg json.RawMessage) ([]rpcRequest, bool, Error) { - var in []jsonRequest - if err := json.Unmarshal(incomingMsg, &in); err != nil { - return nil, false, &invalidMessageError{err.Error()} - } - - requests := make([]rpcRequest, len(in)) - for i, r := range in { - if err := checkReqId(r.Id); err != nil { - return nil, false, &invalidMessageError{err.Error()} - } - - id := &in[i].Id - - // subscribe are special, they will always use `subscriptionMethod` as first param in the payload - if strings.HasSuffix(r.Method, subscribeMethodSuffix) { - requests[i] = rpcRequest{id: id, isPubSub: true} - if len(r.Payload) > 0 { - // first param must be subscription name - var subscribeMethod [1]string - if err := json.Unmarshal(r.Payload, &subscribeMethod); err != nil { - log.Debug(fmt.Sprintf("Unable to parse subscription method: %v\n", err)) - return nil, false, &invalidRequestError{"Unable to parse subscription request"} - } - - requests[i].service, requests[i].method = strings.TrimSuffix(r.Method, subscribeMethodSuffix), subscribeMethod[0] - requests[i].params = r.Payload - continue - } - - return nil, true, &invalidRequestError{"Unable to parse (un)subscribe request arguments"} - } - - if strings.HasSuffix(r.Method, unsubscribeMethodSuffix) { - requests[i] = rpcRequest{id: id, isPubSub: true, method: r.Method, params: r.Payload} +// isBatch returns true when the first non-whitespace characters is '[' +func isBatch(raw json.RawMessage) bool { + for _, c := range raw { + // skip insignificant whitespace (http://www.ietf.org/rfc/rfc4627.txt) + if c == 0x20 || c == 0x09 || c == 0x0a || c == 0x0d { continue } - - if len(r.Payload) == 0 { - requests[i] = rpcRequest{id: id, params: nil} - } else { - requests[i] = rpcRequest{id: id, params: r.Payload} - } - if elem := strings.Split(r.Method, serviceMethodSeparator); len(elem) == 2 { - requests[i].service, requests[i].method = elem[0], elem[1] - } else { - requests[i].err = &methodNotFoundError{r.Method, ""} - } - } - - return requests, true, nil -} - -// ParseRequestArguments tries to parse the given params (json.RawMessage) with the given -// types. It returns the parsed values or an error when the parsing failed. -func (c *jsonCodec) ParseRequestArguments(argTypes []reflect.Type, params interface{}) ([]reflect.Value, Error) { - if args, ok := params.(json.RawMessage); !ok { - return nil, &invalidParamsError{"Invalid params supplied"} - } else { - return parsePositionalArguments(args, argTypes) + return c == '[' } + return false } // parsePositionalArguments tries to parse the given args to an array of values with the // given types. It returns the parsed values or an error when the args could not be // parsed. Missing optional arguments are returned as reflect.Zero values. -func parsePositionalArguments(rawArgs json.RawMessage, types []reflect.Type) ([]reflect.Value, Error) { - // Read beginning of the args array. +func parsePositionalArguments(rawArgs json.RawMessage, types []reflect.Type) ([]reflect.Value, error) { dec := json.NewDecoder(bytes.NewReader(rawArgs)) - if tok, _ := dec.Token(); tok != json.Delim('[') { - return nil, &invalidParamsError{"non-array args"} + var args []reflect.Value + tok, err := dec.Token() + switch { + case err == io.EOF || tok == nil && err == nil: + // "params" is optional and may be empty. Also allow "params":null even though it's + // not in the spec because our own client used to send it. + case err != nil: + return nil, err + case tok == json.Delim('['): + // Read argument array. + if args, err = parseArgumentArray(dec, types); err != nil { + return nil, err + } + default: + return nil, errors.New("non-array args") } - // Read args. + // Set any missing args to nil. + for i := len(args); i < len(types); i++ { + if types[i].Kind() != reflect.Ptr { + return nil, fmt.Errorf("missing value for required argument %d", i) + } + args = append(args, reflect.Zero(types[i])) + } + return args, nil +} + +func parseArgumentArray(dec *json.Decoder, types []reflect.Type) ([]reflect.Value, error) { args := make([]reflect.Value, 0, len(types)) for i := 0; dec.More(); i++ { if i >= len(types) { - return nil, &invalidParamsError{fmt.Sprintf("too many arguments, want at most %d", len(types))} + return args, fmt.Errorf("too many arguments, want at most %d", len(types)) } argval := reflect.New(types[i]) if err := dec.Decode(argval.Interface()); err != nil { - return nil, &invalidParamsError{fmt.Sprintf("invalid argument %d: %v", i, err)} + return args, fmt.Errorf("invalid argument %d: %v", i, err) } if argval.IsNil() && types[i].Kind() != reflect.Ptr { - return nil, &invalidParamsError{fmt.Sprintf("missing value for required argument %d", i)} + return args, fmt.Errorf("missing value for required argument %d", i) } args = append(args, argval.Elem()) } // Read end of args array. - if _, err := dec.Token(); err != nil { - return nil, &invalidParamsError{err.Error()} - } - // Set any missing args to nil. - for i := len(args); i < len(types); i++ { - if types[i].Kind() != reflect.Ptr { - return nil, &invalidParamsError{fmt.Sprintf("missing value for required argument %d", i)} - } - args = append(args, reflect.Zero(types[i])) - } - return args, nil -} - -// CreateResponse will create a JSON-RPC success response with the given id and reply as result. -func (c *jsonCodec) CreateResponse(id interface{}, reply interface{}) interface{} { - return &jsonSuccessResponse{Version: jsonrpcVersion, Id: id, Result: reply} -} - -// CreateErrorResponse will create a JSON-RPC error response with the given id and error. -func (c *jsonCodec) CreateErrorResponse(id interface{}, err Error) interface{} { - return &jsonErrResponse{Version: jsonrpcVersion, Id: id, Error: jsonError{Code: err.ErrorCode(), Message: err.Error()}} -} - -// CreateErrorResponseWithInfo will create a JSON-RPC error response with the given id and error. -// info is optional and contains additional information about the error. When an empty string is passed it is ignored. -func (c *jsonCodec) CreateErrorResponseWithInfo(id interface{}, err Error, info interface{}) interface{} { - return &jsonErrResponse{Version: jsonrpcVersion, Id: id, - Error: jsonError{Code: err.ErrorCode(), Message: err.Error(), Data: info}} -} - -// CreateNotification will create a JSON-RPC notification with the given subscription id and event as params. -func (c *jsonCodec) CreateNotification(subid, namespace string, event interface{}) interface{} { - return &jsonNotification{Version: jsonrpcVersion, Method: namespace + notificationMethodSuffix, - Params: jsonSubscription{Subscription: subid, Result: event}} -} - -// Write message to client -func (c *jsonCodec) Write(res interface{}) error { - c.encMu.Lock() - defer c.encMu.Unlock() - - return c.encode(res) + _, err := dec.Token() + return args, err } -// Close the underlying connection -func (c *jsonCodec) Close() { - c.closer.Do(func() { - close(c.closed) - c.rw.Close() - }) -} - -// Closed returns a channel which will be closed when Close is called -func (c *jsonCodec) Closed() <-chan interface{} { - return c.closed +// parseSubscriptionName extracts the subscription name from an encoded argument array. +func parseSubscriptionName(rawArgs json.RawMessage) (string, error) { + dec := json.NewDecoder(bytes.NewReader(rawArgs)) + if tok, _ := dec.Token(); tok != json.Delim('[') { + return "", errors.New("non-array args") + } + v, _ := dec.Token() + method, ok := v.(string) + if !ok { + return "", errors.New("expected subscription name as first argument") + } + return method, nil } diff --git a/rpc/json_test.go b/rpc/json_test.go deleted file mode 100644 index 5048d2f7a0..0000000000 --- a/rpc/json_test.go +++ /dev/null @@ -1,178 +0,0 @@ -// Copyright 2015 The go-ethereum Authors -// This file is part of the go-ethereum library. -// -// The go-ethereum library is free software: you can redistribute it and/or modify -// it under the terms of the GNU Lesser General Public License as published by -// the Free Software Foundation, either version 3 of the License, or -// (at your option) any later version. -// -// The go-ethereum library is distributed in the hope that it will be useful, -// but WITHOUT ANY WARRANTY; without even the implied warranty of -// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the -// GNU Lesser General Public License for more details. -// -// You should have received a copy of the GNU Lesser General Public License -// along with the go-ethereum library. If not, see . - -package rpc - -import ( - "bufio" - "bytes" - "encoding/json" - "reflect" - "strconv" - "testing" -) - -type RWC struct { - *bufio.ReadWriter -} - -func (rwc *RWC) Close() error { - return nil -} - -func TestJSONRequestParsing(t *testing.T) { - server := NewServer() - service := new(Service) - - if err := server.RegisterName("calc", service); err != nil { - t.Fatalf("%v", err) - } - - req := bytes.NewBufferString(`{"id": 1234, "jsonrpc": "2.0", "method": "calc_add", "params": [11, 22]}`) - var str string - reply := bytes.NewBufferString(str) - rw := &RWC{bufio.NewReadWriter(bufio.NewReader(req), bufio.NewWriter(reply))} - - codec := NewJSONCodec(rw) - - requests, batch, err := codec.ReadRequestHeaders() - if err != nil { - t.Fatalf("%v", err) - } - - if batch { - t.Fatalf("Request isn't a batch") - } - - if len(requests) != 1 { - t.Fatalf("Expected 1 request but got %d requests - %v", len(requests), requests) - } - - if requests[0].service != "calc" { - t.Fatalf("Expected service 'calc' but got '%s'", requests[0].service) - } - - if requests[0].method != "add" { - t.Fatalf("Expected method 'Add' but got '%s'", requests[0].method) - } - - if rawId, ok := requests[0].id.(*json.RawMessage); ok { - id, e := strconv.ParseInt(string(*rawId), 0, 64) - if e != nil { - t.Fatalf("%v", e) - } - if id != 1234 { - t.Fatalf("Expected id 1234 but got %d", id) - } - } else { - t.Fatalf("invalid request, expected *json.RawMesage got %T", requests[0].id) - } - - var arg int - args := []reflect.Type{reflect.TypeOf(arg), reflect.TypeOf(arg)} - - v, err := codec.ParseRequestArguments(args, requests[0].params) - if err != nil { - t.Fatalf("%v", err) - } - - if len(v) != 2 { - t.Fatalf("Expected 2 argument values, got %d", len(v)) - } - - if v[0].Int() != 11 || v[1].Int() != 22 { - t.Fatalf("expected %d == 11 && %d == 22", v[0].Int(), v[1].Int()) - } -} - -func TestJSONRequestParamsParsing(t *testing.T) { - - var ( - stringT = reflect.TypeOf("") - intT = reflect.TypeOf(0) - intPtrT = reflect.TypeOf(new(int)) - - stringV = reflect.ValueOf("abc") - i = 1 - intV = reflect.ValueOf(i) - intPtrV = reflect.ValueOf(&i) - ) - - var validTests = []struct { - input string - argTypes []reflect.Type - expected []reflect.Value - }{ - {`[]`, []reflect.Type{}, []reflect.Value{}}, - {`[]`, []reflect.Type{intPtrT}, []reflect.Value{intPtrV}}, - {`[1]`, []reflect.Type{intT}, []reflect.Value{intV}}, - {`[1,"abc"]`, []reflect.Type{intT, stringT}, []reflect.Value{intV, stringV}}, - {`[null]`, []reflect.Type{intPtrT}, []reflect.Value{intPtrV}}, - {`[null,"abc"]`, []reflect.Type{intPtrT, stringT, intPtrT}, []reflect.Value{intPtrV, stringV, intPtrV}}, - {`[null,"abc",null]`, []reflect.Type{intPtrT, stringT, intPtrT}, []reflect.Value{intPtrV, stringV, intPtrV}}, - } - - codec := jsonCodec{} - - for _, test := range validTests { - params := (json.RawMessage)([]byte(test.input)) - args, err := codec.ParseRequestArguments(test.argTypes, params) - - if err != nil { - t.Fatal(err) - } - - var match []interface{} - json.Unmarshal([]byte(test.input), &match) - - if len(args) != len(test.argTypes) { - t.Fatalf("expected %d parsed args, got %d", len(test.argTypes), len(args)) - } - - for i, arg := range args { - expected := test.expected[i] - - if arg.Kind() != expected.Kind() { - t.Errorf("expected type for param %d in %s", i, test.input) - } - - if arg.Kind() == reflect.Int && arg.Int() != expected.Int() { - t.Errorf("expected int(%d), got int(%d) in %s", expected.Int(), arg.Int(), test.input) - } - - if arg.Kind() == reflect.String && arg.String() != expected.String() { - t.Errorf("expected string(%s), got string(%s) in %s", expected.String(), arg.String(), test.input) - } - } - } - - var invalidTests = []struct { - input string - argTypes []reflect.Type - }{ - {`[]`, []reflect.Type{intT}}, - {`[null]`, []reflect.Type{intT}}, - {`[1]`, []reflect.Type{stringT}}, - {`[1,2]`, []reflect.Type{stringT}}, - {`["abc", null]`, []reflect.Type{stringT, intT}}, - } - - for i, test := range invalidTests { - if _, err := codec.ParseRequestArguments(test.argTypes, test.input); err == nil { - t.Errorf("expected test %d - %s to fail", i, test.input) - } - } -} diff --git a/rpc/server.go b/rpc/server.go index 214e1d3ed9..5a92847f20 100644 --- a/rpc/server.go +++ b/rpc/server.go @@ -18,11 +18,7 @@ package rpc import ( "context" - "fmt" - "reflect" - "runtime" - "strings" - "sync" + "io" "sync/atomic" mapset "github.com/deckarep/golang-set" @@ -31,7 +27,9 @@ import ( const MetadataApi = "rpc" -// CodecOption specifies which type of messages this codec supports +// CodecOption specifies which type of messages a codec supports. +// +// Deprecated: this option is no longer honored by Server. type CodecOption int const ( @@ -42,194 +40,87 @@ const ( OptionSubscriptions = 1 << iota // support pub sub ) -// NewServer will create a new server instance with no registered handlers. -func NewServer() *Server { - server := &Server{ - services: make(serviceRegistry), - codecs: mapset.NewSet(), - run: 1, - } +// Server is an RPC server. +type Server struct { + services serviceRegistry + idgen func() ID + run int32 + codecs mapset.Set +} - // register a default service which will provide meta information about the RPC service such as the services and - // methods it offers. +// NewServer creates a new server instance with no registered handlers. +func NewServer() *Server { + server := &Server{idgen: randomIDGenerator(), codecs: mapset.NewSet(), run: 1} + // Register the default service providing meta information about the RPC service such + // as the services and methods it offers. rpcService := &RPCService{server} server.RegisterName(MetadataApi, rpcService) - return server } -// RPCService gives meta information about the server. -// e.g. gives information about the loaded modules. -type RPCService struct { - server *Server -} - -// Modules returns the list of RPC services with their version number -func (s *RPCService) Modules() map[string]string { - modules := make(map[string]string) - for name := range s.server.services { - modules[name] = "1.0" - } - return modules +// RegisterName creates a service for the given receiver type under the given name. When no +// methods on the given receiver match the criteria to be either a RPC method or a +// subscription an error is returned. Otherwise a new service is created and added to the +// service collection this server provides to clients. +func (s *Server) RegisterName(name string, receiver interface{}) error { + return s.services.registerName(name, receiver) } -// RegisterName will create a service for the given rcvr type under the given name. When no methods on the given rcvr -// match the criteria to be either a RPC method or a subscription an error is returned. Otherwise a new service is -// created and added to the service collection this server instance serves. -func (s *Server) RegisterName(name string, rcvr interface{}) error { - if s.services == nil { - s.services = make(serviceRegistry) - } - - svc := new(service) - svc.typ = reflect.TypeOf(rcvr) - rcvrVal := reflect.ValueOf(rcvr) - - if name == "" { - return fmt.Errorf("no service name for type %s", svc.typ.String()) - } - if !isExported(reflect.Indirect(rcvrVal).Type().Name()) { - return fmt.Errorf("%s is not exported", reflect.Indirect(rcvrVal).Type().Name()) - } - - methods, subscriptions := suitableCallbacks(rcvrVal, svc.typ) +// ServeCodec reads incoming requests from codec, calls the appropriate callback and writes +// the response back using the given codec. It will block until the codec is closed or the +// server is stopped. In either case the codec is closed. +// +// Note that codec options are no longer supported. +func (s *Server) ServeCodec(codec ServerCodec, options CodecOption) { + defer codec.Close() - if len(methods) == 0 && len(subscriptions) == 0 { - return fmt.Errorf("Service %T doesn't have any suitable methods/subscriptions to expose", rcvr) + // Don't serve if server is stopped. + if atomic.LoadInt32(&s.run) == 0 { + return } - // already a previous service register under given name, merge methods/subscriptions - if regsvc, present := s.services[name]; present { - for _, m := range methods { - regsvc.callbacks[formatName(m.method.Name)] = m - } - for _, s := range subscriptions { - regsvc.subscriptions[formatName(s.method.Name)] = s - } - return nil - } - - svc.name = name - svc.callbacks, svc.subscriptions = methods, subscriptions + // Add the codec to the set so it can be closed by Stop. + s.codecs.Add(codec) + defer s.codecs.Remove(codec) - s.services[svc.name] = svc - return nil + c := initClient(codec, s.idgen, &s.services) + <-codec.Closed() + c.Close() } -// serveRequest will reads requests from the codec, calls the RPC callback and -// writes the response to the given codec. -// -// If singleShot is true it will process a single request, otherwise it will handle -// requests until the codec returns an error when reading a request (in most cases -// an EOF). It executes requests in parallel when singleShot is false. -func (s *Server) serveRequest(ctx context.Context, codec ServerCodec, singleShot bool, options CodecOption) error { - var pend sync.WaitGroup - - defer func() { - if err := recover(); err != nil { - const size = 64 << 10 - buf := make([]byte, size) - buf = buf[:runtime.Stack(buf, false)] - log.Error(string(buf)) - } - s.codecsMu.Lock() - s.codecs.Remove(codec) - s.codecsMu.Unlock() - }() - - // ctx, cancel := context.WithCancel(context.Background()) - ctx, cancel := context.WithCancel(ctx) - defer cancel() - - // if the codec supports notification include a notifier that callbacks can use - // to send notification to clients. It is tied to the codec/connection. If the - // connection is closed the notifier will stop and cancels all active subscriptions. - if options&OptionSubscriptions == OptionSubscriptions { - ctx = context.WithValue(ctx, notifierKey{}, newNotifier(codec)) - } - s.codecsMu.Lock() - if atomic.LoadInt32(&s.run) != 1 { // server stopped - s.codecsMu.Unlock() - return &shutdownError{} +// serveSingleRequest reads and processes a single RPC request from the given codec. This +// is used to serve HTTP connections. Subscriptions and reverse calls are not allowed in +// this mode. +func (s *Server) serveSingleRequest(ctx context.Context, codec ServerCodec) { + // Don't serve if server is stopped. + if atomic.LoadInt32(&s.run) == 0 { + return } - s.codecs.Add(codec) - s.codecsMu.Unlock() - // test if the server is ordered to stop - for atomic.LoadInt32(&s.run) == 1 { - reqs, batch, err := s.readRequest(codec) - if err != nil { - // If a parsing error occurred, send an error - if err.Error() != "EOF" { - log.Debug(fmt.Sprintf("read error %v\n", err)) - codec.Write(codec.CreateErrorResponse(nil, err)) - } - // Error or end of stream, wait for requests and tear down - pend.Wait() - return nil - } + h := newHandler(ctx, codec, s.idgen, &s.services) + h.allowSubscribe = false + defer h.close(io.EOF, nil) - // check if server is ordered to shutdown and return an error - // telling the client that his request failed. - if atomic.LoadInt32(&s.run) != 1 { - err = &shutdownError{} - if batch { - resps := make([]interface{}, len(reqs)) - for i, r := range reqs { - resps[i] = codec.CreateErrorResponse(&r.id, err) - } - codec.Write(resps) - } else { - codec.Write(codec.CreateErrorResponse(&reqs[0].id, err)) - } - return nil - } - // If a single shot request is executing, run and return immediately - if singleShot { - if batch { - s.execBatch(ctx, codec, reqs) - } else { - s.exec(ctx, codec, reqs[0]) - } - return nil + reqs, batch, err := codec.Read() + if err != nil { + if err != io.EOF { + codec.Write(ctx, errorMessage(&invalidMessageError{"parse error"})) } - // For multi-shot connections, start a goroutine to serve and loop back - pend.Add(1) - - go func(reqs []*serverRequest, batch bool) { - defer pend.Done() - if batch { - s.execBatch(ctx, codec, reqs) - } else { - s.exec(ctx, codec, reqs[0]) - } - }(reqs, batch) + return + } + if batch { + h.handleBatch(reqs) + } else { + h.handleMsg(reqs[0]) } - return nil -} - -// ServeCodec reads incoming requests from codec, calls the appropriate callback and writes the -// response back using the given codec. It will block until the codec is closed or the server is -// stopped. In either case the codec is closed. -func (s *Server) ServeCodec(codec ServerCodec, options CodecOption) { - defer codec.Close() - s.serveRequest(context.Background(), codec, false, options) -} - -// ServeSingleRequest reads and processes a single RPC request from the given codec. It will not -// close the codec unless a non-recoverable error has occurred. Note, this method will return after -// a single request has been processed! -func (s *Server) ServeSingleRequest(ctx context.Context, codec ServerCodec, options CodecOption) { - s.serveRequest(ctx, codec, true, options) } -// Stop will stop reading new requests, wait for stopPendingRequestTimeout to allow pending requests to finish, -// close all codecs which will cancel pending requests/subscriptions. +// Stop stops reading new requests, waits for stopPendingRequestTimeout to allow pending +// requests to finish, then closes all codecs which will cancel pending requests and +// subscriptions. func (s *Server) Stop() { if atomic.CompareAndSwapInt32(&s.run, 1, 0) { - log.Debug("RPC Server shutdown initiatied") - s.codecsMu.Lock() - defer s.codecsMu.Unlock() + log.Debug("RPC server shutting down") s.codecs.Each(func(c interface{}) bool { c.(ServerCodec).Close() return true @@ -237,206 +128,20 @@ func (s *Server) Stop() { } } -// createSubscription will call the subscription callback and returns the subscription id or error. -func (s *Server) createSubscription(ctx context.Context, c ServerCodec, req *serverRequest) (ID, error) { - // subscription have as first argument the context following optional arguments - args := []reflect.Value{req.callb.rcvr, reflect.ValueOf(ctx)} - args = append(args, req.args...) - reply := req.callb.method.Func.Call(args) - - if !reply[1].IsNil() { // subscription creation failed - return "", reply[1].Interface().(error) - } - - return reply[0].Interface().(*Subscription).ID, nil -} - -// handle executes a request and returns the response from the callback. -func (s *Server) handle(ctx context.Context, codec ServerCodec, req *serverRequest) (interface{}, func()) { - if req.err != nil { - return codec.CreateErrorResponse(&req.id, req.err), nil - } - - if req.isUnsubscribe { // cancel subscription, first param must be the subscription id - if len(req.args) >= 1 && req.args[0].Kind() == reflect.String { - notifier, supported := NotifierFromContext(ctx) - if !supported { // interface doesn't support subscriptions (e.g. http) - return codec.CreateErrorResponse(&req.id, &callbackError{ErrNotificationsUnsupported.Error()}), nil - } - - subid := ID(req.args[0].String()) - if err := notifier.unsubscribe(subid); err != nil { - return codec.CreateErrorResponse(&req.id, &callbackError{err.Error()}), nil - } - - return codec.CreateResponse(req.id, true), nil - } - return codec.CreateErrorResponse(&req.id, &invalidParamsError{"Expected subscription id as first argument"}), nil - } - - if req.callb.isSubscribe { - subid, err := s.createSubscription(ctx, codec, req) - if err != nil { - return codec.CreateErrorResponse(&req.id, &callbackError{err.Error()}), nil - } - - // active the subscription after the sub id was successfully sent to the client - activateSub := func() { - notifier, _ := NotifierFromContext(ctx) - notifier.activate(subid, req.svcname) - } - - return codec.CreateResponse(req.id, subid), activateSub - } - - // regular RPC call, prepare arguments - if len(req.args) != len(req.callb.argTypes) { - rpcErr := &invalidParamsError{fmt.Sprintf("%s%s%s expects %d parameters, got %d", - req.svcname, serviceMethodSeparator, req.callb.method.Name, - len(req.callb.argTypes), len(req.args))} - return codec.CreateErrorResponse(&req.id, rpcErr), nil - } - - arguments := []reflect.Value{req.callb.rcvr} - if req.callb.hasCtx { - arguments = append(arguments, reflect.ValueOf(ctx)) - } - if len(req.args) > 0 { - arguments = append(arguments, req.args...) - } - - // execute RPC method and return result - reply := req.callb.method.Func.Call(arguments) - if len(reply) == 0 { - return codec.CreateResponse(req.id, nil), nil - } - if req.callb.errPos >= 0 { // test if method returned an error - if !reply[req.callb.errPos].IsNil() { - e := reply[req.callb.errPos].Interface().(error) - res := codec.CreateErrorResponse(&req.id, &callbackError{e.Error()}) - return res, nil - } - } - return codec.CreateResponse(req.id, reply[0].Interface()), nil -} - -// exec executes the given request and writes the result back using the codec. -func (s *Server) exec(ctx context.Context, codec ServerCodec, req *serverRequest) { - var response interface{} - var callback func() - if req.err != nil { - response = codec.CreateErrorResponse(&req.id, req.err) - } else { - response, callback = s.handle(ctx, codec, req) - } - - if err := codec.Write(response); err != nil { - log.Error(fmt.Sprintf("%v\n", err)) - codec.Close() - } - - // when request was a subscribe request this allows these subscriptions to be actived - if callback != nil { - callback() - } -} - -// execBatch executes the given requests and writes the result back using the codec. -// It will only write the response back when the last request is processed. -func (s *Server) execBatch(ctx context.Context, codec ServerCodec, requests []*serverRequest) { - responses := make([]interface{}, len(requests)) - var callbacks []func() - for i, req := range requests { - if req.err != nil { - responses[i] = codec.CreateErrorResponse(&req.id, req.err) - } else { - var callback func() - if responses[i], callback = s.handle(ctx, codec, req); callback != nil { - callbacks = append(callbacks, callback) - } - } - } - - if err := codec.Write(responses); err != nil { - log.Error(fmt.Sprintf("%v\n", err)) - codec.Close() - } - - // when request holds one of more subscribe requests this allows these subscriptions to be activated - for _, c := range callbacks { - c() - } +// RPCService gives meta information about the server. +// e.g. gives information about the loaded modules. +type RPCService struct { + server *Server } -// readRequest requests the next (batch) request from the codec. It will return the collection -// of requests, an indication if the request was a batch, the invalid request identifier and an -// error when the request could not be read/parsed. -func (s *Server) readRequest(codec ServerCodec) ([]*serverRequest, bool, Error) { - reqs, batch, err := codec.ReadRequestHeaders() - if err != nil { - return nil, batch, err - } - - requests := make([]*serverRequest, len(reqs)) - - // verify requests - for i, r := range reqs { - var ok bool - var svc *service - - if r.err != nil { - requests[i] = &serverRequest{id: r.id, err: r.err} - continue - } - - if r.isPubSub && strings.HasSuffix(r.method, unsubscribeMethodSuffix) { - requests[i] = &serverRequest{id: r.id, isUnsubscribe: true} - argTypes := []reflect.Type{reflect.TypeOf("")} // expect subscription id as first arg - if args, err := codec.ParseRequestArguments(argTypes, r.params); err == nil { - requests[i].args = args - } else { - requests[i].err = &invalidParamsError{err.Error()} - } - continue - } - - if svc, ok = s.services[r.service]; !ok { // rpc method isn't available - requests[i] = &serverRequest{id: r.id, err: &methodNotFoundError{r.service, r.method}} - continue - } - - if r.isPubSub { // eth_subscribe, r.method contains the subscription method name - if callb, ok := svc.subscriptions[r.method]; ok { - requests[i] = &serverRequest{id: r.id, svcname: svc.name, callb: callb} - if r.params != nil && len(callb.argTypes) > 0 { - argTypes := []reflect.Type{reflect.TypeOf("")} - argTypes = append(argTypes, callb.argTypes...) - if args, err := codec.ParseRequestArguments(argTypes, r.params); err == nil { - requests[i].args = args[1:] // first one is service.method name which isn't an actual argument - } else { - requests[i].err = &invalidParamsError{err.Error()} - } - } - } else { - requests[i] = &serverRequest{id: r.id, err: &methodNotFoundError{r.service, r.method}} - } - continue - } - - if callb, ok := svc.callbacks[r.method]; ok { // lookup RPC method - requests[i] = &serverRequest{id: r.id, svcname: svc.name, callb: callb} - if r.params != nil && len(callb.argTypes) > 0 { - if args, err := codec.ParseRequestArguments(callb.argTypes, r.params); err == nil { - requests[i].args = args - } else { - requests[i].err = &invalidParamsError{err.Error()} - } - } - continue - } +// Modules returns the list of RPC services with their version number +func (s *RPCService) Modules() map[string]string { + s.server.services.mu.Lock() + defer s.server.services.mu.Unlock() - requests[i] = &serverRequest{id: r.id, err: &methodNotFoundError{r.service, r.method}} + modules := make(map[string]string) + for name := range s.server.services.services { + modules[name] = "1.0" } - - return requests, batch, nil + return modules } diff --git a/rpc/server_test.go b/rpc/server_test.go index 90d62f26d8..39099546bb 100644 --- a/rpc/server_test.go +++ b/rpc/server_test.go @@ -17,146 +17,136 @@ package rpc import ( - "context" - "encoding/json" + "bufio" + "bytes" + "io" + "io/ioutil" "net" - "reflect" + "path/filepath" + "strings" "testing" "time" ) -type Service struct{} - -type Args struct { - S string -} - -func (s *Service) NoArgsRets() { -} - -type Result struct { - String string - Int int - Args *Args -} - -func (s *Service) Echo(str string, i int, args *Args) Result { - return Result{str, i, args} -} - -func (s *Service) EchoWithCtx(ctx context.Context, str string, i int, args *Args) Result { - return Result{str, i, args} -} - -func (s *Service) Sleep(ctx context.Context, duration time.Duration) { - select { - case <-time.After(duration): - case <-ctx.Done(): - } -} - -func (s *Service) Rets() (string, error) { - return "", nil -} - -func (s *Service) InvalidRets1() (error, string) { - return nil, "" -} - -func (s *Service) InvalidRets2() (string, string) { - return "", "" -} - -func (s *Service) InvalidRets3() (string, string, error) { - return "", "", nil -} - -func (s *Service) Subscription(ctx context.Context) (*Subscription, error) { - return nil, nil -} - func TestServerRegisterName(t *testing.T) { server := NewServer() - service := new(Service) + service := new(testService) - if err := server.RegisterName("calc", service); err != nil { + if err := server.RegisterName("test", service); err != nil { t.Fatalf("%v", err) } - if len(server.services) != 2 { - t.Fatalf("Expected 2 service entries, got %d", len(server.services)) + if len(server.services.services) != 2 { + t.Fatalf("Expected 2 service entries, got %d", len(server.services.services)) } - svc, ok := server.services["calc"] + svc, ok := server.services.services["test"] if !ok { t.Fatalf("Expected service calc to be registered") } - if len(svc.callbacks) != 5 { - t.Errorf("Expected 5 callbacks for service 'calc', got %d", len(svc.callbacks)) - } - - if len(svc.subscriptions) != 1 { - t.Errorf("Expected 1 subscription for service 'calc', got %d", len(svc.subscriptions)) + wantCallbacks := 7 + if len(svc.callbacks) != wantCallbacks { + t.Errorf("Expected %d callbacks for service 'service', got %d", wantCallbacks, len(svc.callbacks)) } } -func testServerMethodExecution(t *testing.T, method string) { - server := NewServer() - service := new(Service) - - if err := server.RegisterName("test", service); err != nil { - t.Fatalf("%v", err) +func TestServer(t *testing.T) { + files, err := ioutil.ReadDir("testdata") + if err != nil { + t.Fatal("where'd my testdata go?") } + for _, f := range files { + if f.IsDir() || strings.HasPrefix(f.Name(), ".") { + continue + } + path := filepath.Join("testdata", f.Name()) + name := strings.TrimSuffix(f.Name(), filepath.Ext(f.Name())) + t.Run(name, func(t *testing.T) { + runTestScript(t, path) + }) + } +} - stringArg := "string arg" - intArg := 1122 - argsArg := &Args{"abcde"} - params := []interface{}{stringArg, intArg, argsArg} - - request := map[string]interface{}{ - "id": 12345, - "method": "test_" + method, - "version": "2.0", - "params": params, +func runTestScript(t *testing.T, file string) { + server := newTestServer() + content, err := ioutil.ReadFile(file) + if err != nil { + t.Fatal(err) } clientConn, serverConn := net.Pipe() defer clientConn.Close() - - go server.ServeCodec(NewJSONCodec(serverConn), OptionMethodInvocation) - - out := json.NewEncoder(clientConn) - in := json.NewDecoder(clientConn) - - if err := out.Encode(request); err != nil { - t.Fatal(err) + go server.ServeCodec(NewJSONCodec(serverConn), OptionMethodInvocation|OptionSubscriptions) + readbuf := bufio.NewReader(clientConn) + for _, line := range strings.Split(string(content), "\n") { + line = strings.TrimSpace(line) + switch { + case len(line) == 0 || strings.HasPrefix(line, "//"): + // skip comments, blank lines + continue + case strings.HasPrefix(line, "--> "): + t.Log(line) + // write to connection + clientConn.SetWriteDeadline(time.Now().Add(5 * time.Second)) + if _, err := io.WriteString(clientConn, line[4:]+"\n"); err != nil { + t.Fatalf("write error: %v", err) + } + case strings.HasPrefix(line, "<-- "): + t.Log(line) + want := line[4:] + // read line from connection and compare text + clientConn.SetReadDeadline(time.Now().Add(5 * time.Second)) + sent, err := readbuf.ReadString('\n') + if err != nil { + t.Fatalf("read error: %v", err) + } + sent = strings.TrimRight(sent, "\r\n") + if sent != want { + t.Errorf("wrong line from server\ngot: %s\nwant: %s", sent, want) + } + default: + panic("invalid line in test script: " + line) + } } +} - response := jsonSuccessResponse{Result: &Result{}} - if err := in.Decode(&response); err != nil { - t.Fatal(err) - } +// This test checks that responses are delivered for very short-lived connections that +// only carry a single request. +func TestServerShortLivedConn(t *testing.T) { + server := newTestServer() + defer server.Stop() - if result, ok := response.Result.(*Result); ok { - if result.String != stringArg { - t.Errorf("expected %s, got : %s\n", stringArg, result.String) + listener, err := net.Listen("tcp", "127.0.0.1:0") + if err != nil { + t.Fatal("can't listen:", err) + } + defer listener.Close() + go server.ServeListener(listener) + + var ( + request = `{"jsonrpc":"2.0","id":1,"method":"rpc_modules"}` + "\n" + wantResp = `{"jsonrpc":"2.0","id":1,"result":{"nftest":"1.0","rpc":"1.0","test":"1.0"}}` + "\n" + deadline = time.Now().Add(10 * time.Second) + ) + for i := 0; i < 20; i++ { + conn, err := net.Dial("tcp", listener.Addr().String()) + if err != nil { + t.Fatal("can't dial:", err) } - if result.Int != intArg { - t.Errorf("expected %d, got %d\n", intArg, result.Int) + defer conn.Close() + conn.SetDeadline(deadline) + // Write the request, then half-close the connection so the server stops reading. + conn.Write([]byte(request)) + conn.(*net.TCPConn).CloseWrite() + // Now try to get the response. + buf := make([]byte, 2000) + n, err := conn.Read(buf) + if err != nil { + t.Fatal("read error:", err) } - if !reflect.DeepEqual(result.Args, argsArg) { - t.Errorf("expected %v, got %v\n", argsArg, result) + if !bytes.Equal(buf[:n], []byte(wantResp)) { + t.Fatalf("wrong response: %s", buf[:n]) } - } else { - t.Fatalf("invalid response: expected *Result - got: %T", response.Result) } } - -func TestServerMethodExecution(t *testing.T) { - testServerMethodExecution(t, "echo") -} - -func TestServerMethodWithCtx(t *testing.T) { - testServerMethodExecution(t, "echoWithCtx") -} diff --git a/rpc/service.go b/rpc/service.go new file mode 100644 index 0000000000..a9426c6b0e --- /dev/null +++ b/rpc/service.go @@ -0,0 +1,285 @@ +// Copyright 2015 The go-ethereum Authors +// This file is part of the go-ethereum library. +// +// The go-ethereum library is free software: you can redistribute it and/or modify +// it under the terms of the GNU Lesser General Public License as published by +// the Free Software Foundation, either version 3 of the License, or +// (at your option) any later version. +// +// The go-ethereum library is distributed in the hope that it will be useful, +// but WITHOUT ANY WARRANTY; without even the implied warranty of +// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the +// GNU Lesser General Public License for more details. +// +// You should have received a copy of the GNU Lesser General Public License +// along with the go-ethereum library. If not, see . + +package rpc + +import ( + "context" + "errors" + "fmt" + "reflect" + "runtime" + "strings" + "sync" + "unicode" + "unicode/utf8" + + "github.com/ethereum/go-ethereum/log" +) + +var ( + contextType = reflect.TypeOf((*context.Context)(nil)).Elem() + errorType = reflect.TypeOf((*error)(nil)).Elem() + subscriptionType = reflect.TypeOf(Subscription{}) + stringType = reflect.TypeOf("") +) + +type serviceRegistry struct { + mu sync.Mutex + services map[string]service +} + +// service represents a registered object. +type service struct { + name string // name for service + callbacks map[string]*callback // registered handlers + subscriptions map[string]*callback // available subscriptions/notifications +} + +// callback is a method callback which was registered in the server +type callback struct { + fn reflect.Value // the function + rcvr reflect.Value // receiver object of method, set if fn is method + argTypes []reflect.Type // input argument types + hasCtx bool // method's first argument is a context (not included in argTypes) + errPos int // err return idx, of -1 when method cannot return error + isSubscribe bool // true if this is a subscription callback +} + +func (r *serviceRegistry) registerName(name string, rcvr interface{}) error { + rcvrVal := reflect.ValueOf(rcvr) + if name == "" { + return fmt.Errorf("no service name for type %s", rcvrVal.Type().String()) + } + callbacks := suitableCallbacks(rcvrVal) + if len(callbacks) == 0 { + return fmt.Errorf("service %T doesn't have any suitable methods/subscriptions to expose", rcvr) + } + + r.mu.Lock() + defer r.mu.Unlock() + if r.services == nil { + r.services = make(map[string]service) + } + svc, ok := r.services[name] + if !ok { + svc = service{ + name: name, + callbacks: make(map[string]*callback), + subscriptions: make(map[string]*callback), + } + r.services[name] = svc + } + for name, cb := range callbacks { + if cb.isSubscribe { + svc.subscriptions[name] = cb + } else { + svc.callbacks[name] = cb + } + } + return nil +} + +// callback returns the callback corresponding to the given RPC method name. +func (r *serviceRegistry) callback(method string) *callback { + elem := strings.SplitN(method, serviceMethodSeparator, 2) + if len(elem) != 2 { + return nil + } + r.mu.Lock() + defer r.mu.Unlock() + return r.services[elem[0]].callbacks[elem[1]] +} + +// subscription returns a subscription callback in the given service. +func (r *serviceRegistry) subscription(service, name string) *callback { + r.mu.Lock() + defer r.mu.Unlock() + return r.services[service].subscriptions[name] +} + +// suitableCallbacks iterates over the methods of the given type. It determines if a method +// satisfies the criteria for a RPC callback or a subscription callback and adds it to the +// collection of callbacks. See server documentation for a summary of these criteria. +func suitableCallbacks(receiver reflect.Value) map[string]*callback { + typ := receiver.Type() + callbacks := make(map[string]*callback) + for m := 0; m < typ.NumMethod(); m++ { + method := typ.Method(m) + if method.PkgPath != "" { + continue // method not exported + } + cb := newCallback(receiver, method.Func) + if cb == nil { + continue // function invalid + } + name := formatName(method.Name) + callbacks[name] = cb + } + return callbacks +} + +// newCallback turns fn (a function) into a callback object. It returns nil if the function +// is unsuitable as an RPC callback. +func newCallback(receiver, fn reflect.Value) *callback { + fntype := fn.Type() + c := &callback{fn: fn, rcvr: receiver, errPos: -1, isSubscribe: isPubSub(fntype)} + // Determine parameter types. They must all be exported or builtin types. + c.makeArgTypes() + if !allExportedOrBuiltin(c.argTypes) { + return nil + } + // Verify return types. The function must return at most one error + // and/or one other non-error value. + outs := make([]reflect.Type, fntype.NumOut()) + for i := 0; i < fntype.NumOut(); i++ { + outs[i] = fntype.Out(i) + } + if len(outs) > 2 || !allExportedOrBuiltin(outs) { + return nil + } + // If an error is returned, it must be the last returned value. + switch { + case len(outs) == 1 && isErrorType(outs[0]): + c.errPos = 0 + case len(outs) == 2: + if isErrorType(outs[0]) || !isErrorType(outs[1]) { + return nil + } + c.errPos = 1 + } + return c +} + +// makeArgTypes composes the argTypes list. +func (c *callback) makeArgTypes() { + fntype := c.fn.Type() + // Skip receiver and context.Context parameter (if present). + firstArg := 0 + if c.rcvr.IsValid() { + firstArg++ + } + if fntype.NumIn() > firstArg && fntype.In(firstArg) == contextType { + c.hasCtx = true + firstArg++ + } + // Add all remaining parameters. + c.argTypes = make([]reflect.Type, fntype.NumIn()-firstArg) + for i := firstArg; i < fntype.NumIn(); i++ { + c.argTypes[i-firstArg] = fntype.In(i) + } +} + +// call invokes the callback. +func (c *callback) call(ctx context.Context, method string, args []reflect.Value) (res interface{}, errRes error) { + // Create the argument slice. + fullargs := make([]reflect.Value, 0, 2+len(args)) + if c.rcvr.IsValid() { + fullargs = append(fullargs, c.rcvr) + } + if c.hasCtx { + fullargs = append(fullargs, reflect.ValueOf(ctx)) + } + fullargs = append(fullargs, args...) + + // Catch panic while running the callback. + defer func() { + if err := recover(); err != nil { + const size = 64 << 10 + buf := make([]byte, size) + buf = buf[:runtime.Stack(buf, false)] + log.Error("RPC method " + method + " crashed: " + fmt.Sprintf("%v\n%s", err, buf)) + errRes = errors.New("method handler crashed") + } + }() + // Run the callback. + results := c.fn.Call(fullargs) + if len(results) == 0 { + return nil, nil + } + if c.errPos >= 0 && !results[c.errPos].IsNil() { + // Method has returned non-nil error value. + err := results[c.errPos].Interface().(error) + return reflect.Value{}, err + } + return results[0].Interface(), nil +} + +// Is this an exported - upper case - name? +func isExported(name string) bool { + rune, _ := utf8.DecodeRuneInString(name) + return unicode.IsUpper(rune) +} + +// Are all those types exported or built-in? +func allExportedOrBuiltin(types []reflect.Type) bool { + for _, typ := range types { + for typ.Kind() == reflect.Ptr { + typ = typ.Elem() + } + // PkgPath will be non-empty even for an exported type, + // so we need to check the type name as well. + if !isExported(typ.Name()) && typ.PkgPath() != "" { + return false + } + } + return true +} + +// Is t context.Context or *context.Context? +func isContextType(t reflect.Type) bool { + for t.Kind() == reflect.Ptr { + t = t.Elem() + } + return t == contextType +} + +// Does t satisfy the error interface? +func isErrorType(t reflect.Type) bool { + for t.Kind() == reflect.Ptr { + t = t.Elem() + } + return t.Implements(errorType) +} + +// Is t Subscription or *Subscription? +func isSubscriptionType(t reflect.Type) bool { + for t.Kind() == reflect.Ptr { + t = t.Elem() + } + return t == subscriptionType +} + +// isPubSub tests whether the given method has as as first argument a context.Context and +// returns the pair (Subscription, error). +func isPubSub(methodType reflect.Type) bool { + // numIn(0) is the receiver type + if methodType.NumIn() < 2 || methodType.NumOut() != 2 { + return false + } + return isContextType(methodType.In(1)) && + isSubscriptionType(methodType.Out(0)) && + isErrorType(methodType.Out(1)) +} + +// formatName converts to first character of name to lowercase. +func formatName(name string) string { + ret := []rune(name) + if len(ret) > 0 { + ret[0] = unicode.ToLower(ret[0]) + } + return string(ret) +} diff --git a/rpc/stdio.go b/rpc/stdio.go index ea552cca28..8f6b7bd4bf 100644 --- a/rpc/stdio.go +++ b/rpc/stdio.go @@ -26,8 +26,8 @@ import ( // DialStdIO creates a client on stdin/stdout. func DialStdIO(ctx context.Context) (*Client, error) { - return newClient(ctx, func(_ context.Context) (net.Conn, error) { - return stdioConn{}, nil + return newClient(ctx, func(_ context.Context) (ServerCodec, error) { + return NewJSONCodec(stdioConn{}), nil }) } @@ -45,20 +45,8 @@ func (io stdioConn) Close() error { return nil } -func (io stdioConn) LocalAddr() net.Addr { - return &net.UnixAddr{Name: "stdio", Net: "stdio"} -} - -func (io stdioConn) RemoteAddr() net.Addr { - return &net.UnixAddr{Name: "stdio", Net: "stdio"} -} - -func (io stdioConn) SetDeadline(t time.Time) error { - return &net.OpError{Op: "set", Net: "stdio", Source: nil, Addr: nil, Err: errors.New("deadline not supported")} -} - -func (io stdioConn) SetReadDeadline(t time.Time) error { - return &net.OpError{Op: "set", Net: "stdio", Source: nil, Addr: nil, Err: errors.New("deadline not supported")} +func (io stdioConn) RemoteAddr() string { + return "/dev/stdin" } func (io stdioConn) SetWriteDeadline(t time.Time) error { diff --git a/rpc/subscription.go b/rpc/subscription.go index 6bbb6f75d2..c1e869b8a3 100644 --- a/rpc/subscription.go +++ b/rpc/subscription.go @@ -17,9 +17,19 @@ package rpc import ( + "bufio" + "container/list" "context" + crand "crypto/rand" + "encoding/binary" + "encoding/hex" + "encoding/json" "errors" + "math/rand" + "reflect" + "strings" "sync" + "time" ) var ( @@ -29,121 +39,289 @@ var ( ErrSubscriptionNotFound = errors.New("subscription not found") ) +var globalGen = randomIDGenerator() + // ID defines a pseudo random number that is used to identify RPC subscriptions. type ID string -// a Subscription is created by a notifier and tight to that notifier. The client can use -// this subscription to wait for an unsubscribe request for the client, see Err(). -type Subscription struct { - ID ID - namespace string - err chan error // closed on unsubscribe +// NewID returns a new, random ID. +func NewID() ID { + return globalGen() } -// Err returns a channel that is closed when the client send an unsubscribe request. -func (s *Subscription) Err() <-chan error { - return s.err +// randomIDGenerator returns a function generates a random IDs. +func randomIDGenerator() func() ID { + seed, err := binary.ReadVarint(bufio.NewReader(crand.Reader)) + if err != nil { + seed = int64(time.Now().Nanosecond()) + } + var ( + mu sync.Mutex + rng = rand.New(rand.NewSource(seed)) + ) + return func() ID { + mu.Lock() + defer mu.Unlock() + id := make([]byte, 16) + rng.Read(id) + return encodeID(id) + } } -// notifierKey is used to store a notifier within the connection context. -type notifierKey struct{} - -// Notifier is tight to a RPC connection that supports subscriptions. -// Server callbacks use the notifier to send notifications. -type Notifier struct { - codec ServerCodec - subMu sync.Mutex - active map[ID]*Subscription - inactive map[ID]*Subscription - buffer map[ID][]interface{} // unsent notifications of inactive subscriptions -} - -// newNotifier creates a new notifier that can be used to send subscription -// notifications to the client. -func newNotifier(codec ServerCodec) *Notifier { - return &Notifier{ - codec: codec, - active: make(map[ID]*Subscription), - inactive: make(map[ID]*Subscription), - buffer: make(map[ID][]interface{}), +func encodeID(b []byte) ID { + id := hex.EncodeToString(b) + id = strings.TrimLeft(id, "0") + if id == "" { + id = "0" // ID's are RPC quantities, no leading zero's and 0 is 0x0. } + return ID("0x" + id) } +type notifierKey struct{} + // NotifierFromContext returns the Notifier value stored in ctx, if any. func NotifierFromContext(ctx context.Context) (*Notifier, bool) { n, ok := ctx.Value(notifierKey{}).(*Notifier) return n, ok } +// Notifier is tied to a RPC connection that supports subscriptions. +// Server callbacks use the notifier to send notifications. +type Notifier struct { + h *handler + namespace string + + mu sync.Mutex + sub *Subscription + buffer []json.RawMessage + callReturned bool + activated bool +} + // CreateSubscription returns a new subscription that is coupled to the // RPC connection. By default subscriptions are inactive and notifications // are dropped until the subscription is marked as active. This is done // by the RPC server after the subscription ID is send to the client. func (n *Notifier) CreateSubscription() *Subscription { - s := &Subscription{ID: NewID(), err: make(chan error)} - n.subMu.Lock() - n.inactive[s.ID] = s - n.subMu.Unlock() - return s + n.mu.Lock() + defer n.mu.Unlock() + + if n.sub != nil { + panic("can't create multiple subscriptions with Notifier") + } else if n.callReturned { + panic("can't create subscription after subscribe call has returned") + } + n.sub = &Subscription{ID: n.h.idgen(), namespace: n.namespace, err: make(chan error, 1)} + return n.sub } // Notify sends a notification to the client with the given data as payload. // If an error occurs the RPC connection is closed and the error is returned. func (n *Notifier) Notify(id ID, data interface{}) error { - n.subMu.Lock() - defer n.subMu.Unlock() + enc, err := json.Marshal(data) + if err != nil { + return err + } - if sub, active := n.active[id]; active { - n.send(sub, data) - } else { - n.buffer[id] = append(n.buffer[id], data) + n.mu.Lock() + defer n.mu.Unlock() + + if n.sub == nil { + panic("can't Notify before subscription is created") + } else if n.sub.ID != id { + panic("Notify with wrong ID") + } + if n.activated { + return n.send(n.sub, enc) } + n.buffer = append(n.buffer, enc) return nil } -func (n *Notifier) send(sub *Subscription, data interface{}) error { - notification := n.codec.CreateNotification(string(sub.ID), sub.namespace, data) - err := n.codec.Write(notification) - if err != nil { - n.codec.Close() +// Closed returns a channel that is closed when the RPC connection is closed. +// Deprecated: use subscription error channel +func (n *Notifier) Closed() <-chan interface{} { + return n.h.conn.Closed() +} + +// takeSubscription returns the subscription (if one has been created). No subscription can +// be created after this call. +func (n *Notifier) takeSubscription() *Subscription { + n.mu.Lock() + defer n.mu.Unlock() + n.callReturned = true + return n.sub +} + +// acticate is called after the subscription ID was sent to client. Notifications are +// buffered before activation. This prevents notifications being sent to the client before +// the subscription ID is sent to the client. +func (n *Notifier) activate() error { + n.mu.Lock() + defer n.mu.Unlock() + + for _, data := range n.buffer { + if err := n.send(n.sub, data); err != nil { + return err + } } - return err + n.activated = true + return nil } -// Closed returns a channel that is closed when the RPC connection is closed. -func (n *Notifier) Closed() <-chan interface{} { - return n.codec.Closed() -} - -// unsubscribe a subscription. -// If the subscription could not be found ErrSubscriptionNotFound is returned. -func (n *Notifier) unsubscribe(id ID) error { - n.subMu.Lock() - defer n.subMu.Unlock() - if s, found := n.active[id]; found { - close(s.err) - delete(n.active, id) - return nil +func (n *Notifier) send(sub *Subscription, data json.RawMessage) error { + params, _ := json.Marshal(&subscriptionResult{ID: string(sub.ID), Result: data}) + ctx := context.Background() + return n.h.conn.Write(ctx, &jsonrpcMessage{ + Version: vsn, + Method: n.namespace + notificationMethodSuffix, + Params: params, + }) +} + +// A Subscription is created by a notifier and tight to that notifier. The client can use +// this subscription to wait for an unsubscribe request for the client, see Err(). +type Subscription struct { + ID ID + namespace string + err chan error // closed on unsubscribe +} + +// Err returns a channel that is closed when the client send an unsubscribe request. +func (s *Subscription) Err() <-chan error { + return s.err +} + +// MarshalJSON marshals a subscription as its ID. +func (s *Subscription) MarshalJSON() ([]byte, error) { + return json.Marshal(s.ID) +} + +// ClientSubscription is a subscription established through the Client's Subscribe or +// EthSubscribe methods. +type ClientSubscription struct { + client *Client + etype reflect.Type + channel reflect.Value + namespace string + subid string + in chan json.RawMessage + + quitOnce sync.Once // ensures quit is closed once + quit chan struct{} // quit is closed when the subscription exits + errOnce sync.Once // ensures err is closed once + err chan error +} + +func newClientSubscription(c *Client, namespace string, channel reflect.Value) *ClientSubscription { + sub := &ClientSubscription{ + client: c, + namespace: namespace, + etype: channel.Type().Elem(), + channel: channel, + quit: make(chan struct{}), + err: make(chan error, 1), + in: make(chan json.RawMessage), } - return ErrSubscriptionNotFound -} - -// activate enables a subscription. Until a subscription is enabled all -// notifications are dropped. This method is called by the RPC server after -// the subscription ID was sent to client. This prevents notifications being -// send to the client before the subscription ID is send to the client. -func (n *Notifier) activate(id ID, namespace string) { - n.subMu.Lock() - defer n.subMu.Unlock() - - if sub, found := n.inactive[id]; found { - sub.namespace = namespace - n.active[id] = sub - delete(n.inactive, id) - // Send buffered notifications. - for _, data := range n.buffer[id] { - n.send(sub, data) + return sub +} + +// Err returns the subscription error channel. The intended use of Err is to schedule +// resubscription when the client connection is closed unexpectedly. +// +// The error channel receives a value when the subscription has ended due +// to an error. The received error is nil if Close has been called +// on the underlying client and no other error has occurred. +// +// The error channel is closed when Unsubscribe is called on the subscription. +func (sub *ClientSubscription) Err() <-chan error { + return sub.err +} + +// Unsubscribe unsubscribes the notification and closes the error channel. +// It can safely be called more than once. +func (sub *ClientSubscription) Unsubscribe() { + sub.quitWithError(nil, true) + sub.errOnce.Do(func() { close(sub.err) }) +} + +func (sub *ClientSubscription) quitWithError(err error, unsubscribeServer bool) { + sub.quitOnce.Do(func() { + // The dispatch loop won't be able to execute the unsubscribe call + // if it is blocked on deliver. Close sub.quit first because it + // unblocks deliver. + close(sub.quit) + if unsubscribeServer { + sub.requestUnsubscribe() + } + if err != nil { + if err == ErrClientQuit { + err = nil // Adhere to subscription semantics. + } + sub.err <- err } - delete(n.buffer, id) + }) +} + +func (sub *ClientSubscription) deliver(result json.RawMessage) (ok bool) { + select { + case sub.in <- result: + return true + case <-sub.quit: + return false } } + +func (sub *ClientSubscription) start() { + sub.quitWithError(sub.forward()) +} + +func (sub *ClientSubscription) forward() (err error, unsubscribeServer bool) { + cases := []reflect.SelectCase{ + {Dir: reflect.SelectRecv, Chan: reflect.ValueOf(sub.quit)}, + {Dir: reflect.SelectRecv, Chan: reflect.ValueOf(sub.in)}, + {Dir: reflect.SelectSend, Chan: sub.channel}, + } + buffer := list.New() + defer buffer.Init() + for { + var chosen int + var recv reflect.Value + if buffer.Len() == 0 { + // Idle, omit send case. + chosen, recv, _ = reflect.Select(cases[:2]) + } else { + // Non-empty buffer, send the first queued item. + cases[2].Send = reflect.ValueOf(buffer.Front().Value) + chosen, recv, _ = reflect.Select(cases) + } + + switch chosen { + case 0: // <-sub.quit + return nil, false + case 1: // <-sub.in + val, err := sub.unmarshal(recv.Interface().(json.RawMessage)) + if err != nil { + return err, true + } + if buffer.Len() == maxClientSubscriptionBuffer { + return ErrSubscriptionQueueOverflow, true + } + buffer.PushBack(val) + case 2: // sub.channel<- + cases[2].Send = reflect.Value{} // Don't hold onto the value. + buffer.Remove(buffer.Front()) + } + } +} + +func (sub *ClientSubscription) unmarshal(result json.RawMessage) (interface{}, error) { + val := reflect.New(sub.etype) + err := json.Unmarshal(result, val.Interface()) + return val.Elem().Interface(), err +} + +func (sub *ClientSubscription) requestUnsubscribe() error { + var result interface{} + return sub.client.Call(&result, sub.namespace+unsubscribeMethodSuffix, sub.subid) +} diff --git a/rpc/subscription_test.go b/rpc/subscription_test.go index 24febc9190..eba192450d 100644 --- a/rpc/subscription_test.go +++ b/rpc/subscription_test.go @@ -17,232 +17,62 @@ package rpc import ( - "context" "encoding/json" "fmt" "net" - "sync" + "strings" "testing" "time" ) -type NotificationTestService struct { - mu sync.Mutex - unsubscribed chan string - gotHangSubscriptionReq chan struct{} - unblockHangSubscription chan struct{} -} - -func (s *NotificationTestService) Echo(i int) int { - return i -} - -func (s *NotificationTestService) Unsubscribe(subid string) { - if s.unsubscribed != nil { - s.unsubscribed <- subid - } -} - -func (s *NotificationTestService) SomeSubscription(ctx context.Context, n, val int) (*Subscription, error) { - notifier, supported := NotifierFromContext(ctx) - if !supported { - return nil, ErrNotificationsUnsupported - } - - // by explicitly creating an subscription we make sure that the subscription id is send back to the client - // before the first subscription.Notify is called. Otherwise the events might be send before the response - // for the eth_subscribe method. - subscription := notifier.CreateSubscription() - - go func() { - // test expects n events, if we begin sending event immediately some events - // will probably be dropped since the subscription ID might not be send to - // the client. - for i := 0; i < n; i++ { - if err := notifier.Notify(subscription.ID, val+i); err != nil { - return - } - } - - select { - case <-notifier.Closed(): - case <-subscription.Err(): - } - if s.unsubscribed != nil { - s.unsubscribed <- string(subscription.ID) - } - }() - - return subscription, nil -} - -// HangSubscription blocks on s.unblockHangSubscription before -// sending anything. -func (s *NotificationTestService) HangSubscription(ctx context.Context, val int) (*Subscription, error) { - notifier, supported := NotifierFromContext(ctx) - if !supported { - return nil, ErrNotificationsUnsupported - } - - s.gotHangSubscriptionReq <- struct{}{} - <-s.unblockHangSubscription - subscription := notifier.CreateSubscription() - - go func() { - notifier.Notify(subscription.ID, val) - }() - return subscription, nil -} - -func TestNotifications(t *testing.T) { - server := NewServer() - service := &NotificationTestService{unsubscribed: make(chan string)} - - if err := server.RegisterName("eth", service); err != nil { - t.Fatalf("unable to register test service %v", err) - } - - clientConn, serverConn := net.Pipe() - - go server.ServeCodec(NewJSONCodec(serverConn), OptionMethodInvocation|OptionSubscriptions) - - out := json.NewEncoder(clientConn) - in := json.NewDecoder(clientConn) - - n := 5 - val := 12345 - request := map[string]interface{}{ - "id": 1, - "method": "eth_subscribe", - "version": "2.0", - "params": []interface{}{"someSubscription", n, val}, - } - - // create subscription - if err := out.Encode(request); err != nil { - t.Fatal(err) - } - - var subid string - response := jsonSuccessResponse{Result: subid} - if err := in.Decode(&response); err != nil { - t.Fatal(err) - } - - var ok bool - if _, ok = response.Result.(string); !ok { - t.Fatalf("expected subscription id, got %T", response.Result) - } - - for i := 0; i < n; i++ { - var notification jsonNotification - if err := in.Decode(¬ification); err != nil { - t.Fatalf("%v", err) - } - - if int(notification.Params.Result.(float64)) != val+i { - t.Fatalf("expected %d, got %d", val+i, notification.Params.Result) - } - } - - clientConn.Close() // causes notification unsubscribe callback to be called - select { - case <-service.unsubscribed: - case <-time.After(1 * time.Second): - t.Fatal("Unsubscribe not called after one second") - } -} - -func waitForMessages(t *testing.T, in *json.Decoder, successes chan<- jsonSuccessResponse, - failures chan<- jsonErrResponse, notifications chan<- jsonNotification, errors chan<- error) { - - // read and parse server messages - for { - var rmsg json.RawMessage - if err := in.Decode(&rmsg); err != nil { - return +func TestNewID(t *testing.T) { + hexchars := "0123456789ABCDEFabcdef" + for i := 0; i < 100; i++ { + id := string(NewID()) + if !strings.HasPrefix(id, "0x") { + t.Fatalf("invalid ID prefix, want '0x...', got %s", id) } - var responses []map[string]interface{} - if rmsg[0] == '[' { - if err := json.Unmarshal(rmsg, &responses); err != nil { - errors <- fmt.Errorf("Received invalid message: %s", rmsg) - return - } - } else { - var msg map[string]interface{} - if err := json.Unmarshal(rmsg, &msg); err != nil { - errors <- fmt.Errorf("Received invalid message: %s", rmsg) - return - } - responses = append(responses, msg) + id = id[2:] + if len(id) == 0 || len(id) > 32 { + t.Fatalf("invalid ID length, want len(id) > 0 && len(id) <= 32), got %d", len(id)) } - for _, msg := range responses { - // determine what kind of msg was received and broadcast - // it to over the corresponding channel - if _, found := msg["result"]; found { - successes <- jsonSuccessResponse{ - Version: msg["jsonrpc"].(string), - Id: msg["id"], - Result: msg["result"], - } - continue - } - if _, found := msg["error"]; found { - params := msg["params"].(map[string]interface{}) - failures <- jsonErrResponse{ - Version: msg["jsonrpc"].(string), - Id: msg["id"], - Error: jsonError{int(params["subscription"].(float64)), params["message"].(string), params["data"]}, - } - continue + for i := 0; i < len(id); i++ { + if strings.IndexByte(hexchars, id[i]) == -1 { + t.Fatalf("unexpected byte, want any valid hex char, got %c", id[i]) } - if _, found := msg["params"]; found { - params := msg["params"].(map[string]interface{}) - notifications <- jsonNotification{ - Version: msg["jsonrpc"].(string), - Method: msg["method"].(string), - Params: jsonSubscription{params["subscription"].(string), params["result"]}, - } - continue - } - errors <- fmt.Errorf("Received invalid message: %s", msg) } } } -// TestSubscriptionMultipleNamespaces ensures that subscriptions can exists -// for multiple different namespaces. -func TestSubscriptionMultipleNamespaces(t *testing.T) { +func TestSubscriptions(t *testing.T) { var ( namespaces = []string{"eth", "shh", "bzz"} - service = NotificationTestService{} - subCount = len(namespaces) * 2 + service = ¬ificationTestService{} + subCount = len(namespaces) notificationCount = 3 server = NewServer() clientConn, serverConn = net.Pipe() out = json.NewEncoder(clientConn) in = json.NewDecoder(clientConn) - successes = make(chan jsonSuccessResponse) - failures = make(chan jsonErrResponse) - notifications = make(chan jsonNotification) - errors = make(chan error, 10) + successes = make(chan subConfirmation) + notifications = make(chan subscriptionResult) + errors = make(chan error, subCount*notificationCount+1) ) // setup and start server for _, namespace := range namespaces { - if err := server.RegisterName(namespace, &service); err != nil { + if err := server.RegisterName(namespace, service); err != nil { t.Fatalf("unable to register test service %v", err) } } - go server.ServeCodec(NewJSONCodec(serverConn), OptionMethodInvocation|OptionSubscriptions) defer server.Stop() // wait for message and write them to the given channels - go waitForMessages(t, in, successes, failures, notifications, errors) + go waitForMessages(in, successes, notifications, errors) // create subscriptions one by one for i, namespace := range namespaces { @@ -252,27 +82,11 @@ func TestSubscriptionMultipleNamespaces(t *testing.T) { "version": "2.0", "params": []interface{}{"someSubscription", notificationCount, i}, } - if err := out.Encode(&request); err != nil { t.Fatalf("Could not create subscription: %v", err) } } - // create all subscriptions in 1 batch - var requests []interface{} - for i, namespace := range namespaces { - requests = append(requests, map[string]interface{}{ - "id": i, - "method": fmt.Sprintf("%s_subscribe", namespace), - "version": "2.0", - "params": []interface{}{"someSubscription", notificationCount, i}, - }) - } - - if err := out.Encode(&requests); err != nil { - t.Fatalf("Could not create subscription in batch form: %v", err) - } - timeout := time.After(30 * time.Second) subids := make(map[string]string, subCount) count := make(map[string]int, subCount) @@ -285,17 +99,14 @@ func TestSubscriptionMultipleNamespaces(t *testing.T) { } return done } - for !allReceived() { select { - case suc := <-successes: // subscription created - subids[namespaces[int(suc.Id.(float64))]] = suc.Result.(string) + case confirmation := <-successes: // subscription created + subids[namespaces[confirmation.reqid]] = string(confirmation.subid) case notification := <-notifications: - count[notification.Params.Subscription]++ + count[notification.ID]++ case err := <-errors: t.Fatal(err) - case failure := <-failures: - t.Errorf("received error: %v", failure.Error) case <-timeout: for _, namespace := range namespaces { subid, found := subids[namespace] @@ -311,3 +122,85 @@ func TestSubscriptionMultipleNamespaces(t *testing.T) { } } } + +// This test checks that unsubscribing works. +func TestServerUnsubscribe(t *testing.T) { + // Start the server. + server := newTestServer() + service := ¬ificationTestService{unsubscribed: make(chan string)} + server.RegisterName("nftest2", service) + p1, p2 := net.Pipe() + go server.ServeCodec(NewJSONCodec(p1), OptionMethodInvocation|OptionSubscriptions) + + p2.SetDeadline(time.Now().Add(10 * time.Second)) + + // Subscribe. + p2.Write([]byte(`{"jsonrpc":"2.0","id":1,"method":"nftest2_subscribe","params":["someSubscription",0,10]}`)) + + // Handle received messages. + resps := make(chan subConfirmation) + notifications := make(chan subscriptionResult) + errors := make(chan error) + go waitForMessages(json.NewDecoder(p2), resps, notifications, errors) + + // Receive the subscription ID. + var sub subConfirmation + select { + case sub = <-resps: + case err := <-errors: + t.Fatal(err) + } + + // Unsubscribe and check that it is handled on the server side. + p2.Write([]byte(`{"jsonrpc":"2.0","method":"nftest2_unsubscribe","params":["` + sub.subid + `"]}`)) + for { + select { + case id := <-service.unsubscribed: + if id != string(sub.subid) { + t.Errorf("wrong subscription ID unsubscribed") + } + return + case err := <-errors: + t.Fatal(err) + case <-notifications: + // drop notifications + } + } +} + +type subConfirmation struct { + reqid int + subid ID +} + +func waitForMessages(in *json.Decoder, successes chan subConfirmation, notifications chan subscriptionResult, errors chan error) { + for { + var msg jsonrpcMessage + if err := in.Decode(&msg); err != nil { + errors <- fmt.Errorf("decode error: %v", err) + return + } + switch { + case msg.isNotification(): + var res subscriptionResult + if err := json.Unmarshal(msg.Params, &res); err != nil { + errors <- fmt.Errorf("invalid subscription result: %v", err) + } else { + notifications <- res + } + case msg.isResponse(): + var c subConfirmation + if msg.Error != nil { + errors <- msg.Error + } else if err := json.Unmarshal(msg.Result, &c.subid); err != nil { + errors <- fmt.Errorf("invalid response: %v", err) + } else { + json.Unmarshal(msg.ID, &c.reqid) + successes <- c + } + default: + errors <- fmt.Errorf("unrecognized message: %v", msg) + return + } + } +} diff --git a/rpc/testdata/invalid-badid.js b/rpc/testdata/invalid-badid.js new file mode 100644 index 0000000000..2202b8ccd2 --- /dev/null +++ b/rpc/testdata/invalid-badid.js @@ -0,0 +1,7 @@ +// This test checks processing of messages with invalid ID. + +--> {"id":[],"method":"test_foo"} +<-- {"jsonrpc":"2.0","id":null,"error":{"code":-32600,"message":"invalid request"}} + +--> {"id":{},"method":"test_foo"} +<-- {"jsonrpc":"2.0","id":null,"error":{"code":-32600,"message":"invalid request"}} diff --git a/rpc/testdata/invalid-batch.js b/rpc/testdata/invalid-batch.js new file mode 100644 index 0000000000..f470574fb5 --- /dev/null +++ b/rpc/testdata/invalid-batch.js @@ -0,0 +1,14 @@ +// This test checks the behavior of batches with invalid elements. +// Empty batches are not allowed. Batches may contain junk. + +--> [] +<-- {"jsonrpc":"2.0","id":null,"error":{"code":-32600,"message":"empty batch"}} + +--> [1] +<-- [{"jsonrpc":"2.0","id":null,"error":{"code":-32600,"message":"invalid request"}}] + +--> [1,2,3] +<-- [{"jsonrpc":"2.0","id":null,"error":{"code":-32600,"message":"invalid request"}},{"jsonrpc":"2.0","id":null,"error":{"code":-32600,"message":"invalid request"}},{"jsonrpc":"2.0","id":null,"error":{"code":-32600,"message":"invalid request"}}] + +--> [{"jsonrpc":"2.0","id":1,"method":"test_echo","params":["foo",1]},55,{"jsonrpc":"2.0","id":2,"method":"unknown_method"},{"foo":"bar"}] +<-- [{"jsonrpc":"2.0","id":1,"result":{"String":"foo","Int":1,"Args":null}},{"jsonrpc":"2.0","id":null,"error":{"code":-32600,"message":"invalid request"}},{"jsonrpc":"2.0","id":2,"error":{"code":-32601,"message":"the method unknown_method does not exist/is not available"}},{"jsonrpc":"2.0","id":null,"error":{"code":-32600,"message":"invalid request"}}] diff --git a/rpc/testdata/invalid-idonly.js b/rpc/testdata/invalid-idonly.js new file mode 100644 index 0000000000..79997bee30 --- /dev/null +++ b/rpc/testdata/invalid-idonly.js @@ -0,0 +1,7 @@ +// This test checks processing of messages that contain just the ID and nothing else. + +--> {"id":1} +<-- {"jsonrpc":"2.0","id":1,"error":{"code":-32600,"message":"invalid request"}} + +--> {"jsonrpc":"2.0","id":1} +<-- {"jsonrpc":"2.0","id":1,"error":{"code":-32600,"message":"invalid request"}} diff --git a/rpc/testdata/invalid-nonobj.js b/rpc/testdata/invalid-nonobj.js new file mode 100644 index 0000000000..4b9f4d994c --- /dev/null +++ b/rpc/testdata/invalid-nonobj.js @@ -0,0 +1,4 @@ +// This test checks behavior for invalid requests. + +--> 1 +<-- {"jsonrpc":"2.0","id":null,"error":{"code":-32600,"message":"invalid request"}} diff --git a/rpc/testdata/invalid-syntax.json b/rpc/testdata/invalid-syntax.json new file mode 100644 index 0000000000..b194299603 --- /dev/null +++ b/rpc/testdata/invalid-syntax.json @@ -0,0 +1,5 @@ +// This test checks that an error is written for invalid JSON requests. + +--> 'f +<-- {"jsonrpc":"2.0","id":null,"error":{"code":-32700,"message":"invalid character '\\'' looking for beginning of value"}} + diff --git a/rpc/testdata/reqresp-batch.js b/rpc/testdata/reqresp-batch.js new file mode 100644 index 0000000000..977af76630 --- /dev/null +++ b/rpc/testdata/reqresp-batch.js @@ -0,0 +1,8 @@ +// There is no response for all-notification batches. + +--> [{"jsonrpc":"2.0","method":"test_echo","params":["x",99]}] + +// This test checks regular batch calls. + +--> [{"jsonrpc":"2.0","id":2,"method":"test_echo","params":[]}, {"jsonrpc":"2.0","id": 3,"method":"test_echo","params":["x",3]}] +<-- [{"jsonrpc":"2.0","id":2,"error":{"code":-32602,"message":"missing value for required argument 0"}},{"jsonrpc":"2.0","id":3,"result":{"String":"x","Int":3,"Args":null}}] diff --git a/rpc/testdata/reqresp-echo.js b/rpc/testdata/reqresp-echo.js new file mode 100644 index 0000000000..7a9e90321c --- /dev/null +++ b/rpc/testdata/reqresp-echo.js @@ -0,0 +1,16 @@ +// This test calls the test_echo method. + +--> {"jsonrpc": "2.0", "id": 2, "method": "test_echo", "params": []} +<-- {"jsonrpc":"2.0","id":2,"error":{"code":-32602,"message":"missing value for required argument 0"}} + +--> {"jsonrpc": "2.0", "id": 2, "method": "test_echo", "params": ["x"]} +<-- {"jsonrpc":"2.0","id":2,"error":{"code":-32602,"message":"missing value for required argument 1"}} + +--> {"jsonrpc": "2.0", "id": 2, "method": "test_echo", "params": ["x", 3]} +<-- {"jsonrpc":"2.0","id":2,"result":{"String":"x","Int":3,"Args":null}} + +--> {"jsonrpc": "2.0", "id": 2, "method": "test_echo", "params": ["x", 3, {"S": "foo"}]} +<-- {"jsonrpc":"2.0","id":2,"result":{"String":"x","Int":3,"Args":{"S":"foo"}}} + +--> {"jsonrpc": "2.0", "id": 2, "method": "test_echoWithCtx", "params": ["x", 3, {"S": "foo"}]} +<-- {"jsonrpc":"2.0","id":2,"result":{"String":"x","Int":3,"Args":{"S":"foo"}}} diff --git a/rpc/testdata/reqresp-namedparam.js b/rpc/testdata/reqresp-namedparam.js new file mode 100644 index 0000000000..9a9372b0a7 --- /dev/null +++ b/rpc/testdata/reqresp-namedparam.js @@ -0,0 +1,5 @@ +// This test checks that an error response is sent for calls +// with named parameters. + +--> {"jsonrpc":"2.0","method":"test_echo","params":{"int":23},"id":3} +<-- {"jsonrpc":"2.0","id":3,"error":{"code":-32602,"message":"non-array args"}} diff --git a/rpc/testdata/reqresp-noargsrets.js b/rpc/testdata/reqresp-noargsrets.js new file mode 100644 index 0000000000..e61cc708ba --- /dev/null +++ b/rpc/testdata/reqresp-noargsrets.js @@ -0,0 +1,4 @@ +// This test calls the test_noArgsRets method. + +--> {"jsonrpc": "2.0", "id": "foo", "method": "test_noArgsRets", "params": []} +<-- {"jsonrpc":"2.0","id":"foo","result":null} diff --git a/rpc/testdata/reqresp-nomethod.js b/rpc/testdata/reqresp-nomethod.js new file mode 100644 index 0000000000..58ea6f3079 --- /dev/null +++ b/rpc/testdata/reqresp-nomethod.js @@ -0,0 +1,4 @@ +// This test calls a method that doesn't exist. + +--> {"jsonrpc": "2.0", "id": 2, "method": "invalid_method", "params": [2, 3]} +<-- {"jsonrpc":"2.0","id":2,"error":{"code":-32601,"message":"the method invalid_method does not exist/is not available"}} diff --git a/rpc/testdata/reqresp-noparam.js b/rpc/testdata/reqresp-noparam.js new file mode 100644 index 0000000000..2edf486d9f --- /dev/null +++ b/rpc/testdata/reqresp-noparam.js @@ -0,0 +1,4 @@ +// This test checks that calls with no parameters work. + +--> {"jsonrpc":"2.0","method":"test_noArgsRets","id":3} +<-- {"jsonrpc":"2.0","id":3,"result":null} diff --git a/rpc/testdata/reqresp-paramsnull.js b/rpc/testdata/reqresp-paramsnull.js new file mode 100644 index 0000000000..8a01bae1bb --- /dev/null +++ b/rpc/testdata/reqresp-paramsnull.js @@ -0,0 +1,4 @@ +// This test checks that calls with "params":null work. + +--> {"jsonrpc":"2.0","method":"test_noArgsRets","params":null,"id":3} +<-- {"jsonrpc":"2.0","id":3,"result":null} diff --git a/rpc/testdata/revcall.js b/rpc/testdata/revcall.js new file mode 100644 index 0000000000..695d9858f8 --- /dev/null +++ b/rpc/testdata/revcall.js @@ -0,0 +1,6 @@ +// This test checks reverse calls. + +--> {"jsonrpc":"2.0","id":2,"method":"test_callMeBack","params":["foo",[1]]} +<-- {"jsonrpc":"2.0","id":1,"method":"foo","params":[1]} +--> {"jsonrpc":"2.0","id":1,"result":"my result"} +<-- {"jsonrpc":"2.0","id":2,"result":"my result"} diff --git a/rpc/testdata/revcall2.js b/rpc/testdata/revcall2.js new file mode 100644 index 0000000000..acab46551e --- /dev/null +++ b/rpc/testdata/revcall2.js @@ -0,0 +1,7 @@ +// This test checks reverse calls. + +--> {"jsonrpc":"2.0","id":2,"method":"test_callMeBackLater","params":["foo",[1]]} +<-- {"jsonrpc":"2.0","id":2,"result":null} +<-- {"jsonrpc":"2.0","id":1,"method":"foo","params":[1]} +--> {"jsonrpc":"2.0","id":1,"result":"my result"} + diff --git a/rpc/testdata/subscription.js b/rpc/testdata/subscription.js new file mode 100644 index 0000000000..9f10073010 --- /dev/null +++ b/rpc/testdata/subscription.js @@ -0,0 +1,12 @@ +// This test checks basic subscription support. + +--> {"jsonrpc":"2.0","id":1,"method":"nftest_subscribe","params":["someSubscription",5,1]} +<-- {"jsonrpc":"2.0","id":1,"result":"0x1"} +<-- {"jsonrpc":"2.0","method":"nftest_subscription","params":{"subscription":"0x1","result":1}} +<-- {"jsonrpc":"2.0","method":"nftest_subscription","params":{"subscription":"0x1","result":2}} +<-- {"jsonrpc":"2.0","method":"nftest_subscription","params":{"subscription":"0x1","result":3}} +<-- {"jsonrpc":"2.0","method":"nftest_subscription","params":{"subscription":"0x1","result":4}} +<-- {"jsonrpc":"2.0","method":"nftest_subscription","params":{"subscription":"0x1","result":5}} + +--> {"jsonrpc":"2.0","id":2,"method":"nftest_echo","params":[11]} +<-- {"jsonrpc":"2.0","id":2,"result":11} diff --git a/rpc/testservice_test.go b/rpc/testservice_test.go new file mode 100644 index 0000000000..470870bacf --- /dev/null +++ b/rpc/testservice_test.go @@ -0,0 +1,180 @@ +// Copyright 2018 The go-ethereum Authors +// This file is part of the go-ethereum library. +// +// The go-ethereum library is free software: you can redistribute it and/or modify +// it under the terms of the GNU Lesser General Public License as published by +// the Free Software Foundation, either version 3 of the License, or +// (at your option) any later version. +// +// The go-ethereum library is distributed in the hope that it will be useful, +// but WITHOUT ANY WARRANTY; without even the implied warranty of +// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the +// GNU Lesser General Public License for more details. +// +// You should have received a copy of the GNU Lesser General Public License +// along with the go-ethereum library. If not, see . + +package rpc + +import ( + "context" + "encoding/binary" + "errors" + "sync" + "time" +) + +func newTestServer() *Server { + server := NewServer() + server.idgen = sequentialIDGenerator() + if err := server.RegisterName("test", new(testService)); err != nil { + panic(err) + } + if err := server.RegisterName("nftest", new(notificationTestService)); err != nil { + panic(err) + } + return server +} + +func sequentialIDGenerator() func() ID { + var ( + mu sync.Mutex + counter uint64 + ) + return func() ID { + mu.Lock() + defer mu.Unlock() + counter++ + id := make([]byte, 8) + binary.BigEndian.PutUint64(id, counter) + return encodeID(id) + } +} + +type testService struct{} + +type Args struct { + S string +} + +type Result struct { + String string + Int int + Args *Args +} + +func (s *testService) NoArgsRets() {} + +func (s *testService) Echo(str string, i int, args *Args) Result { + return Result{str, i, args} +} + +func (s *testService) EchoWithCtx(ctx context.Context, str string, i int, args *Args) Result { + return Result{str, i, args} +} + +func (s *testService) Sleep(ctx context.Context, duration time.Duration) { + time.Sleep(duration) +} + +func (s *testService) Rets() (string, error) { + return "", nil +} + +func (s *testService) InvalidRets1() (error, string) { + return nil, "" +} + +func (s *testService) InvalidRets2() (string, string) { + return "", "" +} + +func (s *testService) InvalidRets3() (string, string, error) { + return "", "", nil +} + +func (s *testService) CallMeBack(ctx context.Context, method string, args []interface{}) (interface{}, error) { + c, ok := ClientFromContext(ctx) + if !ok { + return nil, errors.New("no client") + } + var result interface{} + err := c.Call(&result, method, args...) + return result, err +} + +func (s *testService) CallMeBackLater(ctx context.Context, method string, args []interface{}) error { + c, ok := ClientFromContext(ctx) + if !ok { + return errors.New("no client") + } + go func() { + <-ctx.Done() + var result interface{} + c.Call(&result, method, args...) + }() + return nil +} + +func (s *testService) Subscription(ctx context.Context) (*Subscription, error) { + return nil, nil +} + +type notificationTestService struct { + unsubscribed chan string + gotHangSubscriptionReq chan struct{} + unblockHangSubscription chan struct{} +} + +func (s *notificationTestService) Echo(i int) int { + return i +} + +func (s *notificationTestService) Unsubscribe(subid string) { + if s.unsubscribed != nil { + s.unsubscribed <- subid + } +} + +func (s *notificationTestService) SomeSubscription(ctx context.Context, n, val int) (*Subscription, error) { + notifier, supported := NotifierFromContext(ctx) + if !supported { + return nil, ErrNotificationsUnsupported + } + + // By explicitly creating an subscription we make sure that the subscription id is send + // back to the client before the first subscription.Notify is called. Otherwise the + // events might be send before the response for the *_subscribe method. + subscription := notifier.CreateSubscription() + go func() { + for i := 0; i < n; i++ { + if err := notifier.Notify(subscription.ID, val+i); err != nil { + return + } + } + select { + case <-notifier.Closed(): + case <-subscription.Err(): + } + if s.unsubscribed != nil { + s.unsubscribed <- string(subscription.ID) + } + }() + return subscription, nil +} + +// HangSubscription blocks on s.unblockHangSubscription before sending anything. +func (s *notificationTestService) HangSubscription(ctx context.Context, val int) (*Subscription, error) { + notifier, supported := NotifierFromContext(ctx) + if !supported { + return nil, ErrNotificationsUnsupported + } + s.gotHangSubscriptionReq <- struct{}{} + <-s.unblockHangSubscription + subscription := notifier.CreateSubscription() + + go func() { + notifier.Notify(subscription.ID, val) + }() + return subscription, nil +} diff --git a/rpc/types.go b/rpc/types.go index 4252c36027..f31f09a774 100644 --- a/rpc/types.go +++ b/rpc/types.go @@ -17,13 +17,11 @@ package rpc import ( + "context" "fmt" "math" - "reflect" "strings" - "sync" - mapset "github.com/deckarep/golang-set" "github.com/ethereum/go-ethereum/common/hexutil" ) @@ -35,57 +33,6 @@ type API struct { Public bool // indication if the methods must be considered safe for public use } -// callback is a method callback which was registered in the server -type callback struct { - rcvr reflect.Value // receiver of method - method reflect.Method // callback - argTypes []reflect.Type // input argument types - hasCtx bool // method's first argument is a context (not included in argTypes) - errPos int // err return idx, of -1 when method cannot return error - isSubscribe bool // indication if the callback is a subscription -} - -// service represents a registered object -type service struct { - name string // name for service - typ reflect.Type // receiver type - callbacks callbacks // registered handlers - subscriptions subscriptions // available subscriptions/notifications -} - -// serverRequest is an incoming request -type serverRequest struct { - id interface{} - svcname string - callb *callback - args []reflect.Value - isUnsubscribe bool - err Error -} - -type serviceRegistry map[string]*service // collection of services -type callbacks map[string]*callback // collection of RPC callbacks -type subscriptions map[string]*callback // collection of subscription callbacks - -// Server represents a RPC server -type Server struct { - services serviceRegistry - - run int32 - codecsMu sync.Mutex - codecs mapset.Set -} - -// rpcRequest represents a raw incoming RPC request -type rpcRequest struct { - service string - method string - id interface{} - isPubSub bool - params interface{} - err Error // invalid batch element -} - // Error wraps RPC errors, which contain an error code in addition to the message. type Error interface { Error() string // returns the message @@ -96,24 +43,19 @@ type Error interface { // a RPC session. Implementations must be go-routine safe since the codec can be called in // multiple go-routines concurrently. type ServerCodec interface { - // Read next request - ReadRequestHeaders() ([]rpcRequest, bool, Error) - // Parse request argument to the given types - ParseRequestArguments(argTypes []reflect.Type, params interface{}) ([]reflect.Value, Error) - // Assemble success response, expects response id and payload - CreateResponse(id interface{}, reply interface{}) interface{} - // Assemble error response, expects response id and error - CreateErrorResponse(id interface{}, err Error) interface{} - // Assemble error response with extra information about the error through info - CreateErrorResponseWithInfo(id interface{}, err Error, info interface{}) interface{} - // Create notification response - CreateNotification(id, namespace string, event interface{}) interface{} - // Write msg to client. - Write(msg interface{}) error - // Close underlying data stream + Read() (msgs []*jsonrpcMessage, isBatch bool, err error) Close() - // Closed when underlying connection is closed + jsonWriter +} + +// jsonWriter can write JSON messages to its underlying connection. +// Implementations must be safe for concurrent use. +type jsonWriter interface { + Write(context.Context, interface{}) error + // Closed returns a channel which is closed when the connection is closed. Closed() <-chan interface{} + // RemoteAddr returns the peer address of the connection. + RemoteAddr() string } type BlockNumber int64 diff --git a/rpc/utils.go b/rpc/utils.go deleted file mode 100644 index 7f7ac4520b..0000000000 --- a/rpc/utils.go +++ /dev/null @@ -1,226 +0,0 @@ -// Copyright 2015 The go-ethereum Authors -// This file is part of the go-ethereum library. -// -// The go-ethereum library is free software: you can redistribute it and/or modify -// it under the terms of the GNU Lesser General Public License as published by -// the Free Software Foundation, either version 3 of the License, or -// (at your option) any later version. -// -// The go-ethereum library is distributed in the hope that it will be useful, -// but WITHOUT ANY WARRANTY; without even the implied warranty of -// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the -// GNU Lesser General Public License for more details. -// -// You should have received a copy of the GNU Lesser General Public License -// along with the go-ethereum library. If not, see . - -package rpc - -import ( - "bufio" - "context" - crand "crypto/rand" - "encoding/binary" - "encoding/hex" - "math/rand" - "reflect" - "strings" - "sync" - "time" - "unicode" - "unicode/utf8" -) - -var ( - subscriptionIDGenMu sync.Mutex - subscriptionIDGen = idGenerator() -) - -// Is this an exported - upper case - name? -func isExported(name string) bool { - rune, _ := utf8.DecodeRuneInString(name) - return unicode.IsUpper(rune) -} - -// Is this type exported or a builtin? -func isExportedOrBuiltinType(t reflect.Type) bool { - for t.Kind() == reflect.Ptr { - t = t.Elem() - } - // PkgPath will be non-empty even for an exported type, - // so we need to check the type name as well. - return isExported(t.Name()) || t.PkgPath() == "" -} - -var contextType = reflect.TypeOf((*context.Context)(nil)).Elem() - -// isContextType returns an indication if the given t is of context.Context or *context.Context type -func isContextType(t reflect.Type) bool { - for t.Kind() == reflect.Ptr { - t = t.Elem() - } - return t == contextType -} - -var errorType = reflect.TypeOf((*error)(nil)).Elem() - -// Implements this type the error interface -func isErrorType(t reflect.Type) bool { - for t.Kind() == reflect.Ptr { - t = t.Elem() - } - return t.Implements(errorType) -} - -var subscriptionType = reflect.TypeOf((*Subscription)(nil)).Elem() - -// isSubscriptionType returns an indication if the given t is of Subscription or *Subscription type -func isSubscriptionType(t reflect.Type) bool { - for t.Kind() == reflect.Ptr { - t = t.Elem() - } - return t == subscriptionType -} - -// isPubSub tests whether the given method has as as first argument a context.Context -// and returns the pair (Subscription, error) -func isPubSub(methodType reflect.Type) bool { - // numIn(0) is the receiver type - if methodType.NumIn() < 2 || methodType.NumOut() != 2 { - return false - } - - return isContextType(methodType.In(1)) && - isSubscriptionType(methodType.Out(0)) && - isErrorType(methodType.Out(1)) -} - -// formatName will convert to first character to lower case -func formatName(name string) string { - ret := []rune(name) - if len(ret) > 0 { - ret[0] = unicode.ToLower(ret[0]) - } - return string(ret) -} - -// suitableCallbacks iterates over the methods of the given type. It will determine if a method satisfies the criteria -// for a RPC callback or a subscription callback and adds it to the collection of callbacks or subscriptions. See server -// documentation for a summary of these criteria. -func suitableCallbacks(rcvr reflect.Value, typ reflect.Type) (callbacks, subscriptions) { - callbacks := make(callbacks) - subscriptions := make(subscriptions) - -METHODS: - for m := 0; m < typ.NumMethod(); m++ { - method := typ.Method(m) - mtype := method.Type - mname := formatName(method.Name) - if method.PkgPath != "" { // method must be exported - continue - } - - var h callback - h.isSubscribe = isPubSub(mtype) - h.rcvr = rcvr - h.method = method - h.errPos = -1 - - firstArg := 1 - numIn := mtype.NumIn() - if numIn >= 2 && mtype.In(1) == contextType { - h.hasCtx = true - firstArg = 2 - } - - if h.isSubscribe { - h.argTypes = make([]reflect.Type, numIn-firstArg) // skip rcvr type - for i := firstArg; i < numIn; i++ { - argType := mtype.In(i) - if isExportedOrBuiltinType(argType) { - h.argTypes[i-firstArg] = argType - } else { - continue METHODS - } - } - - subscriptions[mname] = &h - continue METHODS - } - - // determine method arguments, ignore first arg since it's the receiver type - // Arguments must be exported or builtin types - h.argTypes = make([]reflect.Type, numIn-firstArg) - for i := firstArg; i < numIn; i++ { - argType := mtype.In(i) - if !isExportedOrBuiltinType(argType) { - continue METHODS - } - h.argTypes[i-firstArg] = argType - } - - // check that all returned values are exported or builtin types - for i := 0; i < mtype.NumOut(); i++ { - if !isExportedOrBuiltinType(mtype.Out(i)) { - continue METHODS - } - } - - // when a method returns an error it must be the last returned value - h.errPos = -1 - for i := 0; i < mtype.NumOut(); i++ { - if isErrorType(mtype.Out(i)) { - h.errPos = i - break - } - } - - if h.errPos >= 0 && h.errPos != mtype.NumOut()-1 { - continue METHODS - } - - switch mtype.NumOut() { - case 0, 1, 2: - if mtype.NumOut() == 2 && h.errPos == -1 { // method must one return value and 1 error - continue METHODS - } - callbacks[mname] = &h - } - } - - return callbacks, subscriptions -} - -// idGenerator helper utility that generates a (pseudo) random sequence of -// bytes that are used to generate identifiers. -func idGenerator() *rand.Rand { - if seed, err := binary.ReadVarint(bufio.NewReader(crand.Reader)); err == nil { - return rand.New(rand.NewSource(seed)) - } - return rand.New(rand.NewSource(int64(time.Now().Nanosecond()))) -} - -// NewID generates a identifier that can be used as an identifier in the RPC interface. -// e.g. filter and subscription identifier. -func NewID() ID { - subscriptionIDGenMu.Lock() - defer subscriptionIDGenMu.Unlock() - - id := make([]byte, 16) - for i := 0; i < len(id); i += 7 { - val := subscriptionIDGen.Int63() - for j := 0; i+j < len(id) && j < 7; j++ { - id[i+j] = byte(val) - val >>= 8 - } - } - - rpcId := hex.EncodeToString(id) - // rpc ID's are RPC quantities, no leading zero's and 0 is 0x0 - rpcId = strings.TrimLeft(rpcId, "0") - if rpcId == "" { - rpcId = "0" - } - - return ID("0x" + rpcId) -} diff --git a/rpc/utils_test.go b/rpc/utils_test.go deleted file mode 100644 index e0e063f607..0000000000 --- a/rpc/utils_test.go +++ /dev/null @@ -1,43 +0,0 @@ -// Copyright 2016 The go-ethereum Authors -// This file is part of the go-ethereum library. -// -// The go-ethereum library is free software: you can redistribute it and/or modify -// it under the terms of the GNU Lesser General Public License as published by -// the Free Software Foundation, either version 3 of the License, or -// (at your option) any later version. -// -// The go-ethereum library is distributed in the hope that it will be useful, -// but WITHOUT ANY WARRANTY; without even the implied warranty of -// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the -// GNU Lesser General Public License for more details. -// -// You should have received a copy of the GNU Lesser General Public License -// along with the go-ethereum library. If not, see . - -package rpc - -import ( - "strings" - "testing" -) - -func TestNewID(t *testing.T) { - hexchars := "0123456789ABCDEFabcdef" - for i := 0; i < 100; i++ { - id := string(NewID()) - if !strings.HasPrefix(id, "0x") { - t.Fatalf("invalid ID prefix, want '0x...', got %s", id) - } - - id = id[2:] - if len(id) == 0 || len(id) > 32 { - t.Fatalf("invalid ID length, want len(id) > 0 && len(id) <= 32), got %d", len(id)) - } - - for i := 0; i < len(id); i++ { - if strings.IndexByte(hexchars, id[i]) == -1 { - t.Fatalf("unexpected byte, want any valid hex char, got %c", id[i]) - } - } - } -} diff --git a/rpc/websocket.go b/rpc/websocket.go index eae8320e56..b8e067a5f2 100644 --- a/rpc/websocket.go +++ b/rpc/websocket.go @@ -22,6 +22,7 @@ import ( "crypto/tls" "encoding/base64" "encoding/json" + "errors" "fmt" "net" "net/http" @@ -56,24 +57,39 @@ var websocketJSONCodec = websocket.Codec{ // // allowedOrigins should be a comma-separated list of allowed origin URLs. // To allow connections with any origin, pass "*". -func (srv *Server) WebsocketHandler(allowedOrigins []string) http.Handler { +func (s *Server) WebsocketHandler(allowedOrigins []string) http.Handler { return websocket.Server{ Handshake: wsHandshakeValidator(allowedOrigins), Handler: func(conn *websocket.Conn) { - // Create a custom encode/decode pair to enforce payload size and number encoding - conn.MaxPayloadBytes = maxRequestContentLength - - encoder := func(v interface{}) error { - return websocketJSONCodec.Send(conn, v) - } - decoder := func(v interface{}) error { - return websocketJSONCodec.Receive(conn, v) - } - srv.ServeCodec(NewCodec(conn, encoder, decoder), OptionMethodInvocation|OptionSubscriptions) + codec := newWebsocketCodec(conn) + s.ServeCodec(codec, OptionMethodInvocation|OptionSubscriptions) }, } } +func newWebsocketCodec(conn *websocket.Conn) ServerCodec { + // Create a custom encode/decode pair to enforce payload size and number encoding + conn.MaxPayloadBytes = maxRequestContentLength + encoder := func(v interface{}) error { + return websocketJSONCodec.Send(conn, v) + } + decoder := func(v interface{}) error { + return websocketJSONCodec.Receive(conn, v) + } + rpcconn := Conn(conn) + if conn.IsServerConn() { + // Override remote address with the actual socket address because + // package websocket crashes if there is no request origin. + addr := conn.Request().RemoteAddr + if wsaddr := conn.RemoteAddr().(*websocket.Addr); wsaddr.URL != nil { + // Add origin if present. + addr += "(" + wsaddr.URL.String() + ")" + } + rpcconn = connWithRemoteAddr{conn, addr} + } + return NewCodec(rpcconn, encoder, decoder) +} + // NewWSServer creates a new websocket RPC server around an API provider. // // Deprecated: use Server.WebsocketHandler @@ -105,15 +121,16 @@ func wsHandshakeValidator(allowedOrigins []string) func(*websocket.Config, *http } } - log.Debug(fmt.Sprintf("Allowed origin(s) for WS RPC interface %v\n", origins.ToSlice())) + log.Debug(fmt.Sprintf("Allowed origin(s) for WS RPC interface %v", origins.ToSlice())) f := func(cfg *websocket.Config, req *http.Request) error { + // Verify origin against whitelist. origin := strings.ToLower(req.Header.Get("Origin")) if allowAllOrigins || origins.Contains(origin) { return nil } - log.Warn(fmt.Sprintf("origin '%s' not allowed on WS-RPC interface\n", origin)) - return fmt.Errorf("origin %s not allowed", origin) + log.Warn("Rejected WebSocket connection", "origin", origin) + return errors.New("origin not allowed") } return f @@ -155,8 +172,12 @@ func DialWebsocket(ctx context.Context, endpoint, origin string) (*Client, error return nil, err } - return newClient(ctx, func(ctx context.Context) (net.Conn, error) { - return wsDialContext(ctx, config) + return newClient(ctx, func(ctx context.Context) (ServerCodec, error) { + conn, err := wsDialContext(ctx, config) + if err != nil { + return nil, err + } + return newWebsocketCodec(conn), nil }) }