Gracefully handle disconnected clients

We'll get `Errno::ECONNRESET` if the client forcibly disconnected.
Just close the socket rather than raising the exception.

Handle other errors in `ClientSocket#write`, too, mirroring the Faye
error handling which swallows all `StandardError` on write.

3 files changed, 4 insertions, 1 deletions

diff --git a/actioncable/lib/action_cable/connection/client_socket.rb b/actioncable/lib/action_cable/connection/client_socket.rb
index 9e4dbcd6e6..7d6de78582 100644
--- a/actioncable/lib/action_cable/connection/client_socket.rb
+++ b/actioncable/lib/action_cable/connection/client_socket.rb
@@ -71,6 +71,8 @@ module ActionCable
 
       def write(data)
         @stream.write(data)
+      rescue => e
+        emit_error e.message
       end
 
       def transmit(message)
diff --git a/actioncable/lib/action_cable/connection/faye_client_socket.rb b/actioncable/lib/action_cable/connection/faye_client_socket.rb
index c9139b6858..47d09a9e14 100644
--- a/actioncable/lib/action_cable/connection/faye_client_socket.rb
+++ b/actioncable/lib/action_cable/connection/faye_client_socket.rb
@@ -36,6 +36,7 @@ module ActionCable
           @faye.on(:open)    { |event| @event_target.on_open }
           @faye.on(:message) { |event| @event_target.on_message(event.data) }
           @faye.on(:close)   { |event| @event_target.on_close(event.reason, event.code) }
+          @faye.on(:error)   { |event| @event_target.on_error(event.message) }
         end
     end
   end
diff --git a/actioncable/lib/action_cable/connection/stream.rb b/actioncable/lib/action_cable/connection/stream.rb
index 2d97b28c09..0cf59091bc 100644
--- a/actioncable/lib/action_cable/connection/stream.rb
+++ b/actioncable/lib/action_cable/connection/stream.rb
@@ -29,7 +29,7 @@ module ActionCable
       def write(data)
         return @rack_hijack_io.write(data) if @rack_hijack_io
         return @stream_send.call(data) if @stream_send
-      rescue EOFError
+      rescue EOFError, Errno::ECONNRESET
         @socket_object.client_gone
       end