Revert "Merge pull request #22977 from rails/revert-22934-master"

This reverts commit d0393fcc, reversing
changes made to 3b7ccadf.

Gemfile.lock

@@ -31,8 +31,8 @@ PATH
   specs:
     actioncable (5.0.0.beta1)
       actionpack (= 5.0.0.beta1)
-      celluloid (~> 0.17.2)
       coffee-rails (~> 4.1.0)
+      concurrent-ruby (~> 1.0.0)
       em-hiredis (~> 0.3.0)
       faye-websocket (~> 0.10.0)
       redis (~> 3.0)

actioncable/README.md

@@ -427,7 +427,7 @@ messages back and forth over the WebSocket cable connection. This dependency may
 be alleviated in the future, but for the moment that's what it is. So be sure to have
 Redis installed and running.
 
-The Ruby side of things is built on top of [faye-websocket](https://github.com/faye/faye-websocket-ruby) and [celluloid](https://github.com/celluloid/celluloid).
+The Ruby side of things is built on top of [faye-websocket](https://github.com/faye/faye-websocket-ruby) and [concurrent-ruby](https://github.com/ruby-concurrency/concurrent-ruby).
 
 
 ## Deployment

actioncable/actioncable.gemspec

@@ -23,7 +23,6 @@
   s.add_dependency 'coffee-rails',     '~> 4.1.0'
   s.add_dependency 'faye-websocket',   '~> 0.10.0'
   s.add_dependency 'websocket-driver', '~> 0.6.1'
-  s.add_dependency 'celluloid',        '~> 0.17.2'
   s.add_dependency 'em-hiredis',       '~> 0.3.0'
   s.add_dependency 'redis',            '~> 3.0'
 

actioncable/lib/action_cable/channel/periodic_timers.rb

@@ -28,7 +28,7 @@ def active_periodic_timers
         def start_periodic_timers
           self.class.periodic_timers.each do |callback, options|
             active_periodic_timers << EventMachine::PeriodicTimer.new(options[:every]) do
-              connection.worker_pool.async.run_periodic_timer(self, callback)
+              connection.worker_pool.async_run_periodic_timer(self, callback)
             end
           end
         end

actioncable/lib/action_cable/connection/base.rb

@@ -103,7 +103,7 @@ def close
 
       # Invoke a method on the connection asynchronously through the pool of thread workers.
       def send_async(method, *arguments)
-        worker_pool.async.invoke(self, method, *arguments)
+        worker_pool.async_invoke(self, method, *arguments)
       end
 
       # Return a basic hash of statistics for the connection keyed with `identifier`, `started_at`, and `subscriptions`.

actioncable/lib/action_cable/process/logging.rb

 require 'action_cable/server'
 require 'eventmachine'
-require 'celluloid'
 
 EM.error_handler do |e|
   puts "Error raised inside the event loop: #{e.message}"
   puts e.backtrace.join("\n")
 end
-
-Celluloid.logger = ActionCable.server.logger

actioncable/lib/action_cable/server/base.rb

-# FIXME: Cargo culted fix from https://github.com/celluloid/celluloid-pool/issues/10
-require 'celluloid/current'
-
 require 'em-hiredis'
 
 module ActionCable

actioncable/lib/action_cable/server/worker.rb

-require 'celluloid'
 require 'active_support/callbacks'
+require 'active_support/core_ext/module/attribute_accessors_per_thread'
+require 'concurrent'
 
 module ActionCable
   module Server
     # Worker used by Server.send_async to do connection work in threads. Only for internal use.
     class Worker
       include ActiveSupport::Callbacks
-      include Celluloid
 
-      attr_reader :connection
+      thread_mattr_accessor :connection
       define_callbacks :work
       include ActiveRecordConnectionManagement
 
+      def initialize(max_size: 5)
+        @pool = Concurrent::ThreadPoolExecutor.new(
+          min_threads: 1,
+          max_threads: max_size,
+          max_queue: 0,
+        )
+      end
+
+      def async_invoke(receiver, method, *args)
+        @pool.post do
+          invoke(receiver, method, *args)
+        end
+      end
+
       def invoke(receiver, method, *args)
-        @connection = receiver
+        begin
+          self.connection = receiver
 
-        run_callbacks :work do
-          receiver.send method, *args
+          run_callbacks :work do
+            receiver.send method, *args
+          end
+        rescue Exception => e
+          logger.error "There was an exception - #{e.class}(#{e.message})"
+          logger.error e.backtrace.join("\n")
+
+          receiver.handle_exception if receiver.respond_to?(:handle_exception)
+        ensure
+          self.connection = nil
         end
-      rescue Exception => e
-        logger.error "There was an exception - #{e.class}(#{e.message})"
-        logger.error e.backtrace.join("\n")
+      end
 
-        receiver.handle_exception if receiver.respond_to?(:handle_exception)
+      def async_run_periodic_timer(channel, callback)
+        @pool.post do
+          run_periodic_timer(channel, callback)
+        end
       end
 
       def run_periodic_timer(channel, callback)
-        @connection = channel.connection
+        begin
+          self.connection = channel.connection
 
-        run_callbacks :work do
-          callback.respond_to?(:call) ? channel.instance_exec(&callback) : channel.send(callback)
+          run_callbacks :work do
+            callback.respond_to?(:call) ? channel.instance_exec(&callback) : channel.send(callback)
+          end
+        ensure
+          self.connection = nil
         end
       end
 
       private
+
         def logger
           ActionCable.server.logger
         end

actioncable/test/connection/authorization_test.rb

@@ -10,7 +10,6 @@ def connect
     end
 
     def send_async(method, *args)
-      # Bypass Celluloid
       send method, *args
     end
   end

actioncable/test/connection/base_test.rb

@@ -14,7 +14,6 @@ def disconnect
     end
 
     def send_async(method, *args)
-      # Bypass Celluloid
       send method, *args
     end
   end

actioncable/test/connection/cross_site_forgery_test.rb

@@ -6,7 +6,6 @@ class ActionCable::Connection::CrossSiteForgeryTest < ActionCable::TestCase
 
   class Connection < ActionCable::Connection::Base
     def send_async(method, *args)
-      # Bypass Celluloid
       send method, *args
     end
   end

actioncable/test/connection/string_identifier_test.rb

@@ -10,7 +10,6 @@ def connect
     end
 
     def send_async(method, *args)
-      # Bypass Celluloid
       send method, *args
     end
   end

actioncable/test/connection/subscriptions_test.rb

@@ -5,7 +5,6 @@ class Connection < ActionCable::Connection::Base
     attr_reader :websocket
 
     def send_async(method, *args)
-      # Bypass Celluloid
       send method, *args
     end
   end

actioncable/test/test_helper.rb

@@ -14,11 +14,6 @@
 # Require all the stubs and models
 Dir[File.dirname(__FILE__) + '/stubs/*.rb'].each {|file| require file }
 
-$CELLULOID_DEBUG = false
-$CELLULOID_TEST  = false
-require 'celluloid'
-Celluloid.logger = Logger.new(StringIO.new)
-
 require 'faye/websocket'
 class << Faye::WebSocket
   remove_method :ensure_reactor_running

actioncable/test/worker_test.rb

@@ -17,8 +17,6 @@ def connection
   end
 
   setup do
-    Celluloid.boot
-
     @worker = ActionCable::Server::Worker.new
     @receiver = Receiver.new
   end