Revert handle_info/2 callback (#319)

* Revert "Document handle_info/2 (#317)"

This reverts commit 4776530.

* Revert "Proxy info messages to the adapter (#316)"

This reverts commit 5d088f7.

Author: ruslandoga

examples/tcp_connection/lib/tcp_connection.ex

@@ -64,8 +64,6 @@ defmodule TCPConnection do
 
     case :gen_tcp.connect(host, port, socket_opts, timeout) do
       {:ok, sock} ->
-        # Monitor the socket so we can react to it being closed. See handle_info/2.
-        _ref = :inet.monitor(sock)
         {:ok, {sock, <<>>}}
 
       {:error, reason} ->
@@ -145,21 +143,6 @@ defmodule TCPConnection do
     end
   end
 
-  # The handle_info callback is optional and can be removed if not needed.
-  # Here it is used to react to `:inet.monitor/1` messages which arrive
-  # when socket gets closed while the connection is idle.
-  def handle_info({:DOWN, _ref, _type, sock, _info}, {sock, _buffer}) do
-    {:disconnect, TCPConnection.Error.exception({:idle, :closed})}
-  end
-
-  def handle_info(msg, state) do
-    Logger.info(fn ->
-      ["#{__MODULE__} (", inspect(self()), ") missed message: ", inspect(msg)]
-    end)
-
-    :ok
-  end
-
   @impl true
   def handle_close(_, _, s) do
     {:ok, nil, s}

integration_test/cases/info_test.exs

@@ -362,15 +362,6 @@ defmodule DBConnection do
   """
   @callback disconnect(err :: Exception.t(), state :: any) :: :ok
 
-  @doc """
-  Optional callback for handling messages received by the connection.
-
-  Returns `{:disconnect, exception}` to close the connection or `:ok` to continue.
-  """
-  @callback handle_info(message :: any, state :: any) :: {:disconnect, Exception.t()} | :ok
-
-  @optional_callbacks handle_info: 2
-
   @connection_module_key :connection_module
 
   @doc """

lib/db_connection.ex

@@ -330,22 +330,12 @@ defmodule DBConnection.Connection do
     handle_timeout(s)
   end
 
-  def handle_event(:info, msg, :no_state, %{mod: mod, state: state} = s) do
-    if function_exported?(mod, :handle_info, 2) do
-      case apply(mod, :handle_info, [msg, state]) do
-        :ok ->
-          handle_timeout(s)
-
-        {:disconnect, err} ->
-          {:keep_state, s, {:next_event, :internal, {:disconnect, {:log, err}}}}
-      end
-    else
-      Logger.info(fn ->
-        [inspect(mod), ?\s, ?(, inspect(self()), ") missed message: " | inspect(msg)]
-      end)
+  def handle_event(:info, msg, :no_state, %{mod: mod} = s) do
+    Logger.info(fn ->
+      [inspect(mod), ?\s, ?(, inspect(self()), ") missed message: " | inspect(msg)]
+    end)
 
-      handle_timeout(s)
-    end
+    handle_timeout(s)
   end
 
   @doc false

lib/db_connection/connection.ex

@@ -150,10 +150,6 @@ defmodule TestConnection do
     TestAgent.eval(:handle_deallocate, [query, cursor, opts, state])
   end
 
-  def handle_info(message, state) do
-    TestAgent.eval(:handle_info, [message, state])
-  end
-
   defp put_agent_from_opts(opts) do
     Process.get(:agent) || Process.put(:agent, agent_from_opts(opts))
   end