Added bytes to string method

lib/exw3.ex

@@ -1,78 +1,96 @@
 defmodule ExW3 do
-
-  def reformat_abi abi do
-    Map.new Enum.map(abi, fn x -> {x["name"], x} end)
+  def reformat_abi(abi) do
+    Map.new(Enum.map(abi, fn x -> {x["name"], x} end))
   end
 
-  def load_abi file_path do
-    file = File.read Path.join(System.cwd, file_path)
+  def load_abi(file_path) do
+    file = File.read(Path.join(System.cwd(), file_path))
+
     case file do
-      {:ok, abi} -> reformat_abi Poison.Parser.parse! abi
+      {:ok, abi} -> reformat_abi(Poison.Parser.parse!(abi))
       err -> err
     end
   end
 
-  def decode_output abi, name, output do
-    {:ok, trim_output} = String.slice(output, 2..String.length(output)) |> Base.decode16(case: :lower)
-    output_types = Enum.map abi[name]["outputs"], fn x -> x["type"] end
-    output_signature = Enum.join [name, "(", Enum.join(output_types, ")"), ")"]
+  def decode_output(abi, name, output) do
+    {:ok, trim_output} =
+      String.slice(output, 2..String.length(output)) |> Base.decode16(case: :lower)
+
+    output_types = Enum.map(abi[name]["outputs"], fn x -> x["type"] end)
+    output_signature = Enum.join([name, "(", Enum.join(output_types, ")"), ")"])
     ABI.decode(output_signature, trim_output)
   end
 
-  def encode_inputs abi, name, inputs do
-    input_types = Enum.map abi[name]["inputs"], fn x -> x["type"] end
-    input_signature = Enum.join [name, "(", Enum.join(input_types, ","), ")"]
-    ABI.encode(input_signature, inputs) |> Base.encode16(case: :lower)
+  def encode_input(abi, name, input) do
+    if abi[name]["inputs"] do
+      input_types = Enum.map(abi[name]["inputs"], fn x -> x["type"] end)
+      input_signature = Enum.join([name, "(", Enum.join(input_types, ","), ")"])
+      ABI.encode(input_signature, input) |> Base.encode16(case: :lower)
+    else
+      raise "#{name} method not found with the given abi"
+    end
+  end
+
+  def bytes_to_string bytes do
+    bytes
+    |> Base.encode16(case: :lower)
+    |> String.replace_trailing("0", "")
+    |> Hexate.decode
   end
 
   def accounts do
-    case Ethereumex.HttpClient.eth_accounts do
+    case Ethereumex.HttpClient.eth_accounts() do
       {:ok, accounts} -> accounts
       err -> err
     end
   end
 
-  #Converts ethereum hex string to decimal number
-  def to_decimal hex_string do
+  # Converts ethereum hex string to decimal number
+  def to_decimal(hex_string) do
     hex_string
     |> String.slice(2..-1)
     |> String.to_integer(16)
   end
 
   def block_number do
-    case Ethereumex.HttpClient.eth_block_number do
-      {:ok, block_number} -> 
+    case Ethereumex.HttpClient.eth_block_number() do
+      {:ok, block_number} ->
         block_number |> to_decimal
-      err -> err
+
+      err ->
+        err
     end
   end
 
-  def balance account do
+  def balance(account) do
     case Ethereumex.HttpClient.eth_get_balance(account) do
-      {:ok, balance} -> 
+      {:ok, balance} ->
         balance |> to_decimal
-      err -> err
+
+      err ->
+        err
     end
   end
 
-  def keys_to_decimal map, keys do
+  def keys_to_decimal(map, keys) do
     Map.new(
-      Enum.map keys, fn k ->
-        { k, Map.get(map, k) |> to_decimal }
-      end
+      Enum.map(keys, fn k ->
+        {k, Map.get(map, k) |> to_decimal}
+      end)
     )
   end
 
-  def tx_receipt tx_hash do
+  def tx_receipt(tx_hash) do
     case Ethereumex.HttpClient.eth_get_transaction_receipt(tx_hash) do
-      {:ok, receipt} -> 
-        receipt
-        #Map.merge receipt, keys_to_decimal(receipt, ["blockNumber", "cumulativeGasUsed", "gasUsed"])
-      err -> err
+      {:ok, receipt} ->
+        Map.merge receipt, keys_to_decimal(receipt, ["blockNumber", "cumulativeGasUsed", "gasUsed"])
+
+      err ->
+        err
     end
   end
 
-  def block block_number do
+  def block(block_number) do
     case Ethereumex.HttpClient.eth_get_block_by_number(block_number, true) do
       {:ok, block} -> block
       err -> err
@@ -91,9 +109,9 @@ defmodule ExW3 do
 
   defmodule Contract do
     use Agent
-    
+
     def at(abi, address) do
-      { :ok, pid } = Agent.start_link(fn -> %{abi: abi, address: address} end)
+      {:ok, pid} = Agent.start_link(fn -> %{abi: abi, address: address} end)
       pid
     end
 
@@ -110,40 +128,55 @@ defmodule ExW3 do
 
     def deploy(bin_filename, options) do
       {:ok, bin} = File.read(Path.join(System.cwd(), bin_filename))
+
       tx = %{
         from: options[:from],
         data: bin,
         gas: options[:gas]
       }
+
       {:ok, tx_receipt_id} = Ethereumex.HttpClient.eth_send_transaction(tx)
       {:ok, tx_receipt} = Ethereumex.HttpClient.eth_get_transaction_receipt(tx_receipt_id)
 
       tx_receipt["contractAddress"]
     end
 
-    def method(contract_agent, name, args \\ [], options \\ %{}) do
-      if get(contract_agent, :abi)[name]["constant"] do
-        data = ExW3.encode_inputs(get(contract_agent, :abi), name, args)
-        {:ok, output } = Ethereumex.HttpClient.eth_call(%{
-          to: get(contract_agent, :address),
-          data: data
-        })
-        [ :ok ] ++ ExW3.decode_output(get(contract_agent, :abi), name, output) |> List.to_tuple
+    def method(contract_agent, method_name, args \\ [], options \\ %{}) do
+      method_name = 
+        case method_name |> is_atom do
+          true -> Inflex.camelize(method_name, :lower)
+          false -> method_name
+        end
+
+      input = ExW3.encode_input(get(contract_agent, :abi), method_name, args)
+
+      if get(contract_agent, :abi)[method_name]["constant"] do
+        {:ok, output} =
+          Ethereumex.HttpClient.eth_call(%{
+            to: get(contract_agent, :address),
+            data: input
+          })
+
+        ([:ok] ++ ExW3.decode_output(get(contract_agent, :abi), method_name, output)) |> List.to_tuple()
       else
-        Ethereumex.HttpClient.eth_send_transaction(Map.merge(%{
-          to: get(contract_agent, :address),
-          data: ExW3.encode_inputs(get(contract_agent, :abi), name, args)
-        }, options))
+        Ethereumex.HttpClient.eth_send_transaction(
+          Map.merge(
+            %{
+              to: get(contract_agent, :address),
+              data: input
+            },
+            options
+          )
+        )
       end
     end
-
   end
 
   defmodule EventPublisher do
     use GenServer
 
     def start_link do
-      GenServer.start_link(__MODULE__, %{ block_number: ExW3.block_number})
+      GenServer.start_link(__MODULE__, %{block_number: ExW3.block_number()})
     end
 
     def init(state) do
@@ -157,16 +190,15 @@ defmodule ExW3 do
     end
 
     def handle_info(:block, state) do
-      block_number = ExW3.block_number
-      block = ExW3.block block_number
+      block_number = ExW3.block_number()
+      block = ExW3.block(block_number)
 
-      tx_receipts = Enum.map block["transactions"], fn tx -> ExW3.tx_receipt(tx["hash"]) end
+      tx_receipts = Enum.map(block["transactions"], fn tx -> ExW3.tx_receipt(tx["hash"]) end)
 
       for logs <- Enum.map(tx_receipts, fn receipt -> receipt["logs"] end) do
         for log <- logs do
           for topic <- log["topics"] do
-
-            PubSub.publish String.slice(topic, 2..-1), log["data"]
+            PubSub.publish(String.slice(topic, 2..-1), log["data"])
           end
         end
       end
@@ -178,30 +210,32 @@ defmodule ExW3 do
     defp schedule_block() do
       Process.send_after(self(), :block, 1000)
     end
+  end
 
+  def decode_event(data, signature) do
+    fs = ABI.FunctionSelector.decode(signature)
+
+    data
+    |> Base.decode16!(case: :lower)
+    |> ABI.TypeDecoder.decode(fs)
   end
 
   defmodule EventSubscriber do
-      
-    def start(state) do
-      spawn(fn -> loop(state) end)
+    def start_link(signature, callback) do
+      pid = spawn(fn -> loop(%{callback: callback, signature: signature}) end)
+      ExW3.EventPublisher.subscribe(pid, ExW3.encode_event(signature))
+      {:ok, pid}
     end
 
     def loop(state) do
       receive do
         message ->
-          apply(state[:callback], [message])
+          apply(state[:callback], [
+            ExW3.decode_event(String.slice(message, 2..-1), state[:signature])
+          ])
+
           loop(state)
       end
     end
-    
-  end
-
-  def subscribe signature, callback do
-
-    pid = ExW3.EventSubscriber.start %{callback: callback}
-
-    ExW3.EventPublisher.subscribe pid, ExW3.encode_event(signature)
-
   end
-end
+end

mix.exs

@@ -31,7 +31,9 @@ defmodule ExW3.Mixfile do
       {:ethereumex, "~> 0.3.2"},
       {:abi, "~> 0.1.8"},
       {:poison, "~> 3.1"},
-      {:pubsub, "~> 1.0"}
+      {:pubsub, "~> 1.0"},
+      {:inflex, "~> 1.10.0" },
+      {:hexate,  ">= 0.6.0"}
     ]
   end
 end

mix.lock

@@ -8,6 +8,7 @@
   "hexate": {:hex, :hexate, "0.6.1", "1cea42e462c1daa32223127d4752e71016c3d933d492b9bb7fa4709a4a0fd50d", [:mix], [], "hexpm"},
   "httpoison": {:hex, :httpoison, "1.0.0", "1f02f827148d945d40b24f0b0a89afe40bfe037171a6cf70f2486976d86921cd", [:mix], [{:hackney, "~> 1.8", [hex: :hackney, repo: "hexpm", optional: false]}], "hexpm"},
   "idna": {:hex, :idna, "5.1.0", "d72b4effeb324ad5da3cab1767cb16b17939004e789d8c0ad5b70f3cea20c89a", [:rebar3], [{:unicode_util_compat, "0.3.1", [hex: :unicode_util_compat, repo: "hexpm", optional: false]}], "hexpm"},
+  "inflex": {:hex, :inflex, "1.10.0", "8366a7696e70e1813aca102e61274addf85d99f4a072b2f9c7984054ea1b9d29", [:mix], [], "hexpm"},
   "keccakf1600": {:hex, :keccakf1600_orig, "2.0.0", "0a7217ddb3ee8220d449bbf7575ec39d4e967099f220a91e3dfca4dbaef91963", [:rebar3], [], "hexpm"},
   "libsecp256k1": {:hex, :libsecp256k1, "0.1.3", "57468b986af7c9633527875f71c7ca08bf4150b07b38a60d5bd48fba299ff6c1", [:rebar3], [], "hexpm"},
   "metrics": {:hex, :metrics, "1.0.1", "25f094dea2cda98213cecc3aeff09e940299d950904393b2a29d191c346a8486", [:rebar3], [], "hexpm"},

test/exw3_test.exs

@@ -50,17 +50,17 @@ defmodule EXW3Test do
 
     storage = ExW3.Contract.at context[:simple_storage_abi], contract_address
 
-    {:ok, result} = ExW3.Contract.method(storage, "get")
+    {:ok, result} = ExW3.Contract.method(storage, :get)
 
     assert result == 0
 
-    {:ok, tx_hash} = ExW3.Contract.method(storage, "set", [1], %{from: Enum.at(context[:accounts], 0)})
+    {:ok, tx_hash} = ExW3.Contract.method(storage, :set, [1], %{from: Enum.at(context[:accounts], 0)})
 
     receipt = ExW3.tx_receipt tx_hash
 
     #IO.inspect ExW3.block receipt["blockNumber"]
 
-    {:ok, result} = ExW3.Contract.method(storage, "get")
+    {:ok, result} = ExW3.Contract.method(storage, :get)
 
     assert result == 1
 
@@ -79,9 +79,24 @@ defmodule EXW3Test do
 
     {:ok, event_pub} = ExW3.EventPublisher.start_link
 
-    ExW3.subscribe("Simple(uint256,bytes32)", fn event -> IO.inspect event end)
+    {:ok, pid} = ExW3.EventSubscriber.start_link(
+      "Simple(uint256,bytes32)", 
+      fn event_data ->
+        str =
+          event_data
+          |> Enum.at(1)
+          |> ExW3.bytes_to_string
 
-    {:ok, tx_hash} = ExW3.Contract.method(event_tester, "simple", ["hello, there!"], %{from: Enum.at(context[:accounts], 0)})
+        assert str == "Hello, World!"
+      end
+    )
+
+    {:ok, tx_hash} = ExW3.Contract.method(
+      event_tester, 
+      :simple,
+      ["Hello, World!"],
+      %{from: Enum.at(context[:accounts], 0)}
+    )
 
     receipt = ExW3.tx_receipt tx_hash
 
@@ -91,7 +106,7 @@ defmodule EXW3Test do
 
     assert String.slice(Enum.at(topic, 0), 2..-1) == ExW3.encode_event("Simple(uint256,bytes32)")
 
-    :timer.sleep(5000)
+    :timer.sleep(2000)
 
   end
 
@@ -108,12 +123,12 @@ defmodule EXW3Test do
 
     arr = [1, 2, 3, 4, 5]
 
-    {:ok, result} = ExW3.Contract.method(array_tester, "staticUint", [arr])
+    {:ok, result} = ExW3.Contract.method array_tester, :static_int, [arr]
 
     assert result == arr
 
     #0x5d4e0342
-    {:ok, result} = ExW3.Contract.method(array_tester, "dynamicUint", [arr])
+    {:ok, result} = ExW3.Contract.method array_tester, :dynamic_uint, [arr]
 
     assert result == arr