Add automatic delegations from channel to connection identifiers

2 files changed, 16 insertions, 0 deletions

diff --git a/lib/action_cable/channel/base.rb b/lib/action_cable/channel/base.rb
index 554aca7ffb..87ae3a1211 100644
--- a/lib/action_cable/channel/base.rb
+++ b/lib/action_cable/channel/base.rb
@@ -61,6 +61,9 @@ module ActionCable
     # In this example, subscribed/unsubscribed are not callable methods, as they were already declared in ActionCable::Channel::Base, but #appear/away
     # are. #generate_connection_token is also not callable as its a private method. You'll see that appear accepts a data parameter, which it then
     # uses as part of its model call. #away does not, it's simply a trigger action.
+    #
+    # Also note that in this example, current_user is available because it was marked as an identifying attribute on the connection.
+    # All such identifiers will automatically create a delegation method of the same name on the channel instance.
     class Base
       include Callbacks
       include PeriodicTimers
@@ -77,6 +80,7 @@ module ActionCable
         @identifier = identifier
         @params     = params
 
+        delegate_connection_identifiers
         subscribe_to_channel
       end
 
@@ -123,6 +127,15 @@ module ActionCable
 
 
       private
+        def delegate_connection_identifiers
+          connection.identifiers.each do |identifier|
+            define_singleton_method(identifier) do
+              connection.send(identifier)
+            end
+          end
+        end
+
+
         def subscribe_to_channel
           logger.info "#{self.class.name} subscribing"
           run_subscribe_callbacks
diff --git a/lib/action_cable/connection/identification.rb b/lib/action_cable/connection/identification.rb
index 3ea3b77e56..113e41ca3f 100644
--- a/lib/action_cable/connection/identification.rb
+++ b/lib/action_cable/connection/identification.rb
@@ -11,6 +11,9 @@ module ActionCable
       class_methods do
         # Mark a key as being a connection identifier index that can then used to find the specific connection again later.
         # Common identifiers are current_user and current_account, but could be anything really.
+        #
+        # Note that anything marked as an identifier will automatically create a delegate by the same name on any
+        # channel instances created off the connection.
         def identified_by(*identifiers)
           Array(identifiers).each { |identifier| attr_accessor identifier }
           self.identifiers += identifiers