Added event filtering, with formatted data

lib/exw3.ex

@@ -295,8 +295,8 @@ defmodule ExW3 do
       GenServer.start_link(__MODULE__, [], name: EventPoller)
     end
 
-    def subscribe(filter_id) do
-      GenServer.cast(EventPoller, {:subscribe, filter_id})
+    def filter(filter_id) do
+      GenServer.cast(EventPoller, {:filter, filter_id})
     end
 
     @impl true
@@ -306,7 +306,7 @@ defmodule ExW3 do
     end
 
     @impl true
-    def handle_cast({:subscribe, filter_id}, state) do
+    def handle_cast({:filter, filter_id}, state) do
       {:noreply, [filter_id | state]}
     end
 
@@ -314,7 +314,7 @@ defmodule ExW3 do
     def handle_info(:work, state) do
       # Do the desired work here
       Enum.each state, fn filter_id ->
-	send EventListener, {:event, filter_id, ExW3.get_filter_changes(filter_id)}
+	send Listener, {:event, filter_id, ExW3.get_filter_changes(filter_id)}
       end
       
       schedule_work() # Reschedule once more
@@ -322,21 +322,21 @@ defmodule ExW3 do
     end
 
     defp schedule_work() do
-      Process.send_after(self(), :work, 1000) # In 1 sec
+      Process.send_after(self(), :work, 500) # In 1/2 sec
     end
   end
   
-  defmodule Listener do
+  defmodule EventListener do
     def start_link do
       Poller.start_link()
       {:ok, pid} = Task.start_link(fn -> loop(%{}) end)
-      Process.register(pid, EventListener)
+      Process.register(pid, Listener)
       :ok
     end
 
-    def subscribe(filter_id, pid) do
-      Poller.subscribe(filter_id)
-      send EventListener, {:subscribe, filter_id, pid}
+    def filter(filter_id, event_signature, pid) do
+      Poller.filter(filter_id)
+      send Listener, {:filter, filter_id, event_signature, pid}
     end
 
     def listen(callback) do
@@ -346,13 +346,19 @@ defmodule ExW3 do
       listen(callback)
     end
     
-    defp loop(map) do
+    defp loop(state) do
       receive do
-	{:subscribe, filter_id, pid} ->
-	  loop(Map.put(map, filter_id, pid))
-	{:event, filter_id, data} ->
-	  send Map.get(map, filter_id), {:event, {filter_id, data}}
-	  loop(map)
+	{:filter, filter_id, event_signature, pid} ->
+	  loop(Map.put(state, filter_id, %{pid: pid, signature: event_signature}))
+	{:event, filter_id, logs} ->
+	  filter_attributes = Map.get(state, filter_id)
+	  Enum.each(logs, fn log ->
+	    data = Map.get(log, "data")
+	    new_data = ExW3.decode_event(data, filter_attributes[:signature])
+	    new_log = Map.put(log, :data, new_data)
+	    send filter_attributes[:pid], {:event, {filter_id, new_log}}
+	  end)
+	  loop(state)
       end
     end
   end
@@ -404,8 +410,8 @@ defmodule ExW3 do
       GenServer.call(pid, {:tx_receipt, tx_hash})
     end
 
-    def subscribe(pid, event_name, other_pid, event_data \\ %{}) do
-      GenServer.call(pid, {:subscribe, {event_name, other_pid, event_data}})
+    def filter(pid, event_name, other_pid, event_data \\ %{}) do
+      GenServer.call(pid, {:filter, {event_name, other_pid, event_data}})
     end
 
     # Server
@@ -514,10 +520,14 @@ defmodule ExW3 do
       {:noreply, [{:address, address} | state]}
     end
 
-    def handle_call({:subscribe, {event_name, other_pid, event_data}}, _from, state) do
+    def handle_call({:filter, {event_name, other_pid, event_data}}, _from, state) do
+      unless Process.whereis(Listener) do
+	raise "EventListener process not alive. Call ExW3.EventListener.start_link before using ExW3.Contract.subscribe"
+      end
       payload = Map.merge(%{address: state[:address], topics: [state[:event_names][event_name]]}, event_data)
       filter_id = ExW3.new_filter(payload)
-      Listener.subscribe(filter_id, other_pid)
+      event_signature = state[:events][state[:event_names][event_name]][:signature]
+      EventListener.filter(filter_id, event_signature, other_pid)
       {:reply, filter_id, state ++ [event_name, filter_id]}
     end
 

test/exw3_test.exs

@@ -147,10 +147,12 @@ defmodule EXW3Test do
       )
 
     ExW3.Contract.at(EventTester, address)
-    
-    ExW3.Listener.start_link()
 
-    filter_id = ExW3.Contract.subscribe(EventTester, "Simple", self())
+    {:ok, agent} = Agent.start_link(fn -> [] end)
+  
+    ExW3.EventListener.start_link()
+
+    filter_id = ExW3.Contract.filter(EventTester, "Simple", self())
 
     {:ok, tx_hash} =
       ExW3.Contract.send(
@@ -159,14 +161,17 @@ defmodule EXW3Test do
 	["Hello, World!"],
 	%{from: Enum.at(context[:accounts], 0)}
       )
-    
+  
     receive do
       {:event, {filter_id, data}} ->
-	IO.inspect data
+	Agent.update(agent, fn list -> [data | list] end)	
     after 3_000 ->
 	raise "Never received event"
     end
 
+    state = Agent.get(agent, fn list -> list end)
+    assert Enum.at(state, 0) |> is_map
+
     ExW3.uninstall_filter(filter_id)
   end