From 16a6603956551703e3bbd06101c568a73bcdaa52 Mon Sep 17 00:00:00 2001 From: Matthew Draper Date: Mon, 25 Jan 2016 03:53:27 +1030 Subject: [PATCH] Synchronize the lazy setters in Server They're all at risk of races on the first requests. --- actioncable/lib/action_cable/server/base.rb | 23 +++++++++++++------ .../subscription_adapter/async.rb | 4 ++-- .../subscription_adapter/inline.rb | 11 ++++++++- .../subscription_adapter/postgresql.rb | 7 +++++- .../subscription_adapter/redis.rb | 17 ++++++++++---- 5 files changed, 47 insertions(+), 15 deletions(-) diff --git a/actioncable/lib/action_cable/server/base.rb b/actioncable/lib/action_cable/server/base.rb index b00abd208c..fe48c112df 100644 --- a/actioncable/lib/action_cable/server/base.rb +++ b/actioncable/lib/action_cable/server/base.rb @@ -1,3 +1,5 @@ +require 'thread' + module ActionCable module Server # A singleton ActionCable::Server instance is available via ActionCable.server. It's used by the rack process that starts the cable server, but @@ -13,7 +15,12 @@ class Base def self.logger; config.logger; end delegate :logger, to: :config + attr_reader :mutex + def initialize + @mutex = Mutex.new + + @remote_connections = @stream_event_loop = @worker_pool = @channel_classes = @pubsub = nil end # Called by rack to setup the server. @@ -29,29 +36,31 @@ def disconnect(identifiers) # Gateway to RemoteConnections. See that class for details. def remote_connections - @remote_connections ||= RemoteConnections.new(self) + @remote_connections || @mutex.synchronize { @remote_connections ||= RemoteConnections.new(self) } end def stream_event_loop - @stream_event_loop ||= ActionCable::Connection::StreamEventLoop.new + @stream_event_loop || @mutex.synchronize { @stream_event_loop ||= ActionCable::Connection::StreamEventLoop.new } end # The thread worker pool for handling all the connection work on this server. Default size is set by config.worker_pool_size. def worker_pool - @worker_pool ||= ActionCable::Server::Worker.new(max_size: config.worker_pool_size) + @worker_pool || @mutex.synchronize { @worker_pool ||= ActionCable::Server::Worker.new(max_size: config.worker_pool_size) } end # Requires and returns a hash of all the channel class constants keyed by name. def channel_classes - @channel_classes ||= begin - config.channel_paths.each { |channel_path| require channel_path } - config.channel_class_names.each_with_object({}) { |name, hash| hash[name] = name.constantize } + @channel_classes || @mutex.synchronize do + @channel_classes ||= begin + config.channel_paths.each { |channel_path| require channel_path } + config.channel_class_names.each_with_object({}) { |name, hash| hash[name] = name.constantize } + end end end # Adapter used for all streams/broadcasting. def pubsub - @pubsub ||= config.pubsub_adapter.new(self) + @pubsub || @mutex.synchronize { @pubsub ||= config.pubsub_adapter.new(self) } end # All the identifiers applied to the connection class associated with this server. diff --git a/actioncable/lib/action_cable/subscription_adapter/async.rb b/actioncable/lib/action_cable/subscription_adapter/async.rb index c88b03947a..cca6894289 100644 --- a/actioncable/lib/action_cable/subscription_adapter/async.rb +++ b/actioncable/lib/action_cable/subscription_adapter/async.rb @@ -4,8 +4,8 @@ module ActionCable module SubscriptionAdapter class Async < Inline # :nodoc: private - def subscriber_map - @subscriber_map ||= AsyncSubscriberMap.new + def new_subscriber_map + AsyncSubscriberMap.new end class AsyncSubscriberMap < SubscriberMap diff --git a/actioncable/lib/action_cable/subscription_adapter/inline.rb b/actioncable/lib/action_cable/subscription_adapter/inline.rb index 4a2a8d23a2..81357faead 100644 --- a/actioncable/lib/action_cable/subscription_adapter/inline.rb +++ b/actioncable/lib/action_cable/subscription_adapter/inline.rb @@ -1,6 +1,11 @@ module ActionCable module SubscriptionAdapter class Inline < Base # :nodoc: + def initialize(*) + super + @subscriber_map = nil + end + def broadcast(channel, payload) subscriber_map.broadcast(channel, payload) end @@ -19,7 +24,11 @@ def shutdown private def subscriber_map - @subscriber_map ||= SubscriberMap.new + @subscriber_map || @server.mutex.synchronize { @subscriber_map ||= new_subscriber_map } + end + + def new_subscriber_map + SubscriberMap.new end end end diff --git a/actioncable/lib/action_cable/subscription_adapter/postgresql.rb b/actioncable/lib/action_cable/subscription_adapter/postgresql.rb index 3ce1bbed68..abaeb92e54 100644 --- a/actioncable/lib/action_cable/subscription_adapter/postgresql.rb +++ b/actioncable/lib/action_cable/subscription_adapter/postgresql.rb @@ -5,6 +5,11 @@ module ActionCable module SubscriptionAdapter class PostgreSQL < Base # :nodoc: + def initialize(*) + super + @listener = nil + end + def broadcast(channel, payload) with_connection do |pg_conn| pg_conn.exec("NOTIFY #{pg_conn.escape_identifier(channel)}, '#{pg_conn.escape_string(payload)}'") @@ -37,7 +42,7 @@ def with_connection(&block) # :nodoc: private def listener - @listener ||= Listener.new(self) + @listener || @server.mutex.synchronize { @listener ||= Listener.new(self) } end class Listener < SubscriberMap diff --git a/actioncable/lib/action_cable/subscription_adapter/redis.rb b/actioncable/lib/action_cable/subscription_adapter/redis.rb index a035e3988d..560b79df16 100644 --- a/actioncable/lib/action_cable/subscription_adapter/redis.rb +++ b/actioncable/lib/action_cable/subscription_adapter/redis.rb @@ -13,6 +13,11 @@ module SubscriptionAdapter class Redis < Base # :nodoc: @@mutex = Mutex.new + def initialize(*) + super + @redis_connection_for_broadcasts = @redis_connection_for_subscriptions = nil + end + def broadcast(channel, payload) redis_connection_for_broadcasts.publish(channel, payload) end @@ -35,15 +40,19 @@ def shutdown 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." + @redis_connection_for_subscriptions || @server.mutex.synchronize do + @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." + end end end end def redis_connection_for_broadcasts - @redis_connection_for_broadcasts ||= ::Redis.new(@server.config.cable) + @redis_connection_for_broadcasts || @server.mutex.synchronize do + @redis_connection_for_broadcasts ||= ::Redis.new(@server.config.cable) + end end def ensure_reactor_running -- GitLab