Merge pull request #4 from OpenMatchmaking/feature-configurable_worker

Feature configurable worker

README.md

@@ -14,7 +14,7 @@ The package can be installed via adding the `spotter` dependency to your list of
 
   ```elixir
   def deps do
-    [{:spotter, "~> 0.2.2"}]
+    [{:spotter, "~> 0.3.0"}]
   end
   ```
 
@@ -75,7 +75,8 @@ Any of those arguments (that were mentioned in the documentation) can be specifi
     ])
 
     # Specify here the queue that you want to use
-    def configure(channel, _config) do
+    # `opts` will contain options (as a Map) that were specified in child_spec for supervisor 
+    def configure(channel, _opts) do
       :ok = AMQP.Exchange.direct(channel, @exchange, durable: true)
 
       # An initial point where the worker do required stuff
@@ -89,13 +90,16 @@ Any of those arguments (that were mentioned in the documentation) can be specifi
       # Specify a consumer here
       {:ok, _} = AMQP.Basic.consume(channel, @queue_validate)
 
-      # And dont forget to return the channel
-      {:ok, channel}
+      # You must return here the tuple, where the first element is `:ok` atom, and the
+      # second element whill be any type what you would like. The second element will
+      # be set for the GenServer state, so that you can get an access to it via the
+      # `state[:meta]` expression
+      {:ok, [queue_request: queue_request, queue_forward: queue_forward]}
     end
 
     # Invoked when a message successfully consumed
     def handle_info({:basic_deliver, payload, %{delivery_tag: tag, reply_to: reply_to, headers: headers}}, state) do
-      channel = state[:meta][:channel]
+      channel = state[:channel]
       spawn fn -> consume(channel, tag, reply_to, headers, payload) end
       {:noreply, state}
     end

lib/worker.ex

@@ -27,7 +27,11 @@ defmodule Spotter.Worker do
       end
 
       def start_link() do
-        GenServer.start_link(__MODULE__, config())
+        GenServer.start_link(__MODULE__, %{config: config()})
+      end
+
+      def start_link(opts) do
+        GenServer.start_link(__MODULE__, %{config: config(), opts: opts})
       end
 
       def init(opts) do
@@ -37,17 +41,15 @@ defmodule Spotter.Worker do
             {:error, :noconn}
           _ ->
             @connection.spawn_channel(@channel_name)
-            @connection.configure_channel(@channel_name, opts)
+            @connection.configure_channel(@channel_name, opts[:config])
 
             channel = get_channel()
-            |> configure(opts)
-
-            {:ok, channel}
+            {:ok, [channel: channel, meta: configure(channel, opts[:opts])]}
         end
       end
 
-      def configure(channel, _opts) do
-        channel
+      def configure(_channel, _opts) do
+        {:ok, []}
       end
 
       def validate_config!(config) do
@@ -67,9 +69,9 @@ defmodule Spotter.Worker do
         Spotter.AMQP.Connection.Channel.get_config(@channel_name)
       end
 
-      def handle_call(:status, _from, channel) do
+      def handle_call(:status, _from, state) do
         safe_run fn(_) ->
-          {:reply, AMQP.Queue.status(channel, channel_config()[:queue][:name]), channel}
+          {:reply, AMQP.Queue.status(state[:channel], channel_config()[:queue][:name]), state}
         end
       end
 

mix.exs

@@ -1,7 +1,7 @@
 defmodule Spotter.MixProject do
   use Mix.Project
 
-  @version "0.2.2"
+  @version "0.3.0"
 
   def project do
     [

test/worker_test.exs

@@ -72,12 +72,12 @@ defmodule SpotterWorkerTest do
       :ok = AMQP.Basic.qos(channel, prefetch_count: 1)
       {:ok, _} = AMQP.Basic.consume(channel, @queue_request)
 
-      channel
+      {:ok, []}
     end
 
     # Handle the trapped exit call
     def handle_info({:EXIT, _from, reason}, state) do
-      cleanup(reason, state)
+      cleanup(reason, state[:channel])
       {:stop, reason, state}
     end
 
@@ -97,10 +97,11 @@ defmodule SpotterWorkerTest do
     end
 
     # Invoked when a message successfully consumed
-    def handle_info({:basic_deliver, payload, %{delivery_tag: tag, reply_to: reply_to, headers: headers}}, channel) do
+    def handle_info({:basic_deliver, payload, %{delivery_tag: tag, reply_to: reply_to, headers: headers}}, state) do
+      channel = state[:channel]
       message_headers = Enum.into(Enum.map(headers, fn({key, _, value}) -> {key, value} end), %{})
       spawn fn -> consume(channel, tag, reply_to, message_headers, payload) end
-      {:noreply, channel}
+      {:noreply, state}
     end
 
     def terminate(reason, state) do