Using a hacked faye-websocket, drop EventMachine

9 files changed, 33 insertions, 22 deletions

diff --git a/actioncable/lib/action_cable/channel/periodic_timers.rb b/actioncable/lib/action_cable/channel/periodic_timers.rb
index 7f0fb37afc..56597d02d7 100644
--- a/actioncable/lib/action_cable/channel/periodic_timers.rb
+++ b/actioncable/lib/action_cable/channel/periodic_timers.rb
@@ -27,14 +27,14 @@ module ActionCable
 
         def start_periodic_timers
           self.class.periodic_timers.each do |callback, options|
-            active_periodic_timers << EventMachine::PeriodicTimer.new(options[:every]) do
+            active_periodic_timers << Concurrent::TimerTask.new(execution_interval: options[:every]) do
               connection.worker_pool.async_run_periodic_timer(self, callback)
             end
           end
         end
 
         def stop_periodic_timers
-          active_periodic_timers.each { |timer| timer.cancel }
+          active_periodic_timers.each { |timer| timer.shutdown }
         end
     end
   end
diff --git a/actioncable/lib/action_cable/channel/streams.rb b/actioncable/lib/action_cable/channel/streams.rb
index e2876ef6fa..a26373e387 100644
--- a/actioncable/lib/action_cable/channel/streams.rb
+++ b/actioncable/lib/action_cable/channel/streams.rb
@@ -75,7 +75,7 @@ module ActionCable
         callback ||= default_stream_callback(broadcasting)
         streams << [ broadcasting, callback ]
 
-        EM.next_tick do
+        Concurrent.global_io_executor.post do
           pubsub.subscribe(broadcasting, callback, lambda do
             transmit_subscription_confirmation
             logger.info "#{self.class.name} is streaming from #{broadcasting}"
diff --git a/actioncable/lib/action_cable/connection/internal_channel.rb b/actioncable/lib/action_cable/connection/internal_channel.rb
index 54ed7672d2..27826792b3 100644
--- a/actioncable/lib/action_cable/connection/internal_channel.rb
+++ b/actioncable/lib/action_cable/connection/internal_channel.rb
@@ -15,14 +15,14 @@ module ActionCable
             @_internal_subscriptions ||= []
             @_internal_subscriptions << [ internal_channel, callback ]
 
-            EM.next_tick { pubsub.subscribe(internal_channel, callback) }
+            Concurrent.global_io_executor.post { pubsub.subscribe(internal_channel, callback) }
             logger.info "Registered connection (#{connection_identifier})"
           end
         end
 
         def unsubscribe_from_internal_channel
           if @_internal_subscriptions.present?
-            @_internal_subscriptions.each { |channel, callback| EM.next_tick { pubsub.unsubscribe(channel, callback) } }
+            @_internal_subscriptions.each { |channel, callback| Concurrent.global_io_executor.post { pubsub.unsubscribe(channel, callback) } }
           end
         end
 
diff --git a/actioncable/lib/action_cable/process/logging.rb b/actioncable/lib/action_cable/process/logging.rb
index dce637b3ca..ebb8990891 100644
--- a/actioncable/lib/action_cable/process/logging.rb
+++ b/actioncable/lib/action_cable/process/logging.rb
@@ -1,7 +1,8 @@
 require 'action_cable/server'
-require 'eventmachine'
 
-EM.error_handler do |e|
-  puts "Error raised inside the event loop: #{e.message}"
-  puts e.backtrace.join("\n")
+if defined?(::EventMachine)
+  EventMachine.error_handler do |e|
+    puts "Error raised inside the event loop: #{e.message}"
+    puts e.backtrace.join("\n")
+  end
 end
diff --git a/actioncable/lib/action_cable/server.rb b/actioncable/lib/action_cable/server.rb
index a2a89d5f1e..bd6a3826a3 100644
--- a/actioncable/lib/action_cable/server.rb
+++ b/actioncable/lib/action_cable/server.rb
@@ -1,7 +1,3 @@
-require 'eventmachine'
-EventMachine.epoll  if EventMachine.epoll?
-EventMachine.kqueue if EventMachine.kqueue?
-
 module ActionCable
   module Server
     extend ActiveSupport::Autoload
diff --git a/actioncable/lib/action_cable/server/connections.rb b/actioncable/lib/action_cable/server/connections.rb
index 47dcea8c20..8671dd5ebd 100644
--- a/actioncable/lib/action_cable/server/connections.rb
+++ b/actioncable/lib/action_cable/server/connections.rb
@@ -22,11 +22,9 @@ module ActionCable
       # then can't rely on being able to receive and send to it. So there's a 3 second heartbeat running on all connections. If the beat fails, we automatically
       # disconnect.
       def setup_heartbeat_timer
-        EM.next_tick do
-          @heartbeat_timer ||= EventMachine.add_periodic_timer(BEAT_INTERVAL) do
-            EM.next_tick { connections.map(&:beat) }
-          end
-        end
+        @heartbeat_timer ||= Concurrent::TimerTask.new(execution_interval: BEAT_INTERVAL) do
+          Concurrent.global_io_executor.post { connections.map(&:beat) }
+        end.tap(&:execute)
       end
 
       def open_connections_statistics
diff --git a/actioncable/lib/action_cable/subscription_adapter/async.rb b/actioncable/lib/action_cable/subscription_adapter/async.rb
index 85d4892e4c..c88b03947a 100644
--- a/actioncable/lib/action_cable/subscription_adapter/async.rb
+++ b/actioncable/lib/action_cable/subscription_adapter/async.rb
@@ -10,11 +10,11 @@ module ActionCable
 
         class AsyncSubscriberMap < SubscriberMap
           def add_subscriber(*)
-            ::EM.next_tick { super }
+            Concurrent.global_io_executor.post { super }
           end
 
           def invoke_callback(*)
-            ::EM.next_tick { super }
+            Concurrent.global_io_executor.post { super }
           end
         end
     end
diff --git a/actioncable/lib/action_cable/subscription_adapter/postgresql.rb b/actioncable/lib/action_cable/subscription_adapter/postgresql.rb
index 78f8aeb599..3ce1bbed68 100644
--- a/actioncable/lib/action_cable/subscription_adapter/postgresql.rb
+++ b/actioncable/lib/action_cable/subscription_adapter/postgresql.rb
@@ -63,7 +63,7 @@ module ActionCable
                     case action
                     when :listen
                       pg_conn.exec("LISTEN #{pg_conn.escape_identifier channel}")
-                      ::EM.next_tick(&callback) if callback
+                      Concurrent.global_io_executor << callback if callback
                     when :unlisten
                       pg_conn.exec("UNLISTEN #{pg_conn.escape_identifier channel}")
                     when :shutdown
@@ -93,7 +93,7 @@ module ActionCable
           end
 
           def invoke_callback(*)
-            ::EM.next_tick { super }
+            Concurrent.global_io_executor.post { super }
           end
         end
     end
diff --git a/actioncable/lib/action_cable/subscription_adapter/redis.rb b/actioncable/lib/action_cable/subscription_adapter/redis.rb
index 3b86354621..a035e3988d 100644
--- a/actioncable/lib/action_cable/subscription_adapter/redis.rb
+++ b/actioncable/lib/action_cable/subscription_adapter/redis.rb
@@ -1,11 +1,18 @@
+require 'thread'
+
 gem 'em-hiredis', '~> 0.3.0'
 gem 'redis', '~> 3.0'
 require 'em-hiredis'
 require 'redis'
 
+EventMachine.epoll  if EventMachine.epoll?
+EventMachine.kqueue if EventMachine.kqueue?
+
 module ActionCable
   module SubscriptionAdapter
     class Redis < Base # :nodoc:
+      @@mutex = Mutex.new
+
       def broadcast(channel, payload)
         redis_connection_for_broadcasts.publish(channel, payload)
       end
@@ -27,6 +34,7 @@ module ActionCable
 
       private
         def redis_connection_for_subscriptions
+          ensure_reactor_running
           @redis_connection_for_subscriptions ||= EM::Hiredis.connect(@server.config.cable[:url]).tap do |redis|
             redis.on(:reconnect_failed) do
               @logger.info "[ActionCable] Redis reconnect failed."
@@ -37,6 +45,14 @@ module ActionCable
         def redis_connection_for_broadcasts
           @redis_connection_for_broadcasts ||= ::Redis.new(@server.config.cable)
         end
+
+        def ensure_reactor_running
+          return if EventMachine.reactor_running?
+          @@mutex.synchronize do
+            Thread.new { EventMachine.run } unless EventMachine.reactor_running?
+            Thread.pass until EventMachine.reactor_running?
+          end
+        end
     end
   end
 end