Add default_config, and cfg[:timeout] for tasks

- Using the @default_config attribute in a module will fill out a default
value.
- cfg[:timeout] sets the timeout for the task for this module to finish.
- Update Omnibot.Irc.route_msg/2 to have each task spawn a second task,
  while the first task waits for its child to finish, otherwise killing
  it.

Signed-off-by: Alek Ratzloff <alekratz@gmail.com>

lib/contrib/linkbot.ex

@@ -2,6 +2,8 @@ defmodule Omnibot.Contrib.Linkbot do
   use Omnibot.Module
   require Logger
 
+  @default_config timeout: 30_000
+
   defmodule Client do
     use Tesla
 
@@ -13,6 +15,7 @@ defmodule Omnibot.Contrib.Linkbot do
 
     def get_title(url) do
       if should_get?(url) do
+        Process.sleep(11_000)
         resp = get!(url)
         %{"title" => title} = Regex.named_captures(@title_regex, resp.body)
         title

lib/core.ex

@@ -2,6 +2,8 @@ defmodule Omnibot.Core do
   use Omnibot.Module
   alias Omnibot.State
 
+  @default_config [channels: :all]
+
   @impl true
   def on_join(irc, channel, nick) do
     cfg = State.cfg()

lib/irc.ex

@@ -32,12 +32,22 @@ defmodule Omnibot.Irc do
     channel = Msg.channel(msg)
 
     State.channel_modules(channel)
-    |> Enum.each(fn {module, _} ->
+    |> Enum.each(fn {module, mod_cfg} ->
       # Create a new task for each module
-      {:ok, _task} = Task.Supervisor.start_child(
+      {:ok, _task} =
-        Omnibot.RouterSupervisor,
+        Task.Supervisor.start_child(
-        fn -> module.on_msg(irc, msg) end
+          Omnibot.RouterSupervisor,
-      )
+          fn ->
+            task = Task.Supervisor.async(
+              Omnibot.RouterSupervisor,
+              fn -> module.on_msg(irc, msg) end
+            )
+
+            # Time out after 10 seconds by default
+            timeout = mod_cfg[:timeout] || 10_000
+            Task.await(task, timeout)
+          end
+        )
     end)
   end
 
@@ -54,7 +64,7 @@ defmodule Omnibot.Irc do
     # Wait for first message
     send_msg(self(), "NICK", cfg.nick)
     send_msg(self(), "USER", [cfg.user, "0", "*", cfg.real])
-    :inet.setopts(socket, [active: true])
+    :inet.setopts(socket, active: true)
 
     {:ok, socket}
   end

lib/module.ex

@@ -20,6 +20,9 @@ defmodule Omnibot.Module do
         @impl true
         def on_init(_cfg), do: nil
 
+        @impl true
+        def default_config(), do: @default_config
+
         def commands(), do: MapSet.to_list(@commands)
       end
     end
@@ -97,6 +100,7 @@ defmodule Omnibot.Module do
       defoverridable Module
 
       @commands MapSet.new()
+      @default_config []
       @before_compile Omnibot.Module.Hooks
     end
   end
@@ -114,6 +118,7 @@ defmodule Omnibot.Module do
   @callback on_part(irc :: pid(), channel :: String.t(), nick :: String.t()) :: any
   @callback on_kick(irc :: pid(), channel :: String.t(), nick :: String.t(), target :: String.t()) :: any
   @callback on_init(cfg :: any) :: any
+  @callback default_config() :: any
 
   defmacro command(cmd, opts) do
     quote generated: true do

lib/module_supervisor.ex

@@ -15,16 +15,15 @@ defmodule Omnibot.ModuleSupervisor do
 
     # These are modules that need to be loaded for core functionality of the bot
     core = [
-      {Omnibot.Core, cfg: [channels: :all]},
+      Omnibot.Core
     ]
 
     # Map the modules in the configuration to the children
     children =
-      core ++
+      for mod <- (core ++ cfg.modules) do
-      for mod <- cfg.modules do
         case mod do
-          {name, cfg} -> {name, cfg: cfg, name: name}
+          {name, cfg} -> {name, cfg: cfg ++ name.default_config(), name: name}
-          name -> {name, cfg: [], name: name}
+          name -> {name, cfg: name.default_config(), name: name}
         end
       end