aboutsummaryrefslogtreecommitdiffstats
path: root/actioncable/lib/action_cable/connection/stream_event_loop.rb
diff options
context:
space:
mode:
Diffstat (limited to 'actioncable/lib/action_cable/connection/stream_event_loop.rb')
-rw-r--r--actioncable/lib/action_cable/connection/stream_event_loop.rb103
1 files changed, 103 insertions, 0 deletions
diff --git a/actioncable/lib/action_cable/connection/stream_event_loop.rb b/actioncable/lib/action_cable/connection/stream_event_loop.rb
new file mode 100644
index 0000000000..2abad09c03
--- /dev/null
+++ b/actioncable/lib/action_cable/connection/stream_event_loop.rb
@@ -0,0 +1,103 @@
+require 'nio'
+require 'thread'
+
+module ActionCable
+ module Connection
+ class StreamEventLoop
+ def initialize
+ @nio = @thread = nil
+ @map = {}
+ @stopping = false
+ @todo = Queue.new
+
+ @spawn_mutex = Mutex.new
+ end
+
+ def timer(interval, &block)
+ Concurrent::TimerTask.new(execution_interval: interval, &block).tap(&:execute)
+ end
+
+ def post(task = nil, &block)
+ task ||= block
+
+ Concurrent.global_io_executor << task
+ end
+
+ def attach(io, stream)
+ @todo << lambda do
+ @map[io] = stream
+ @nio.register(io, :r)
+ end
+ wakeup
+ end
+
+ def detach(io, stream)
+ @todo << lambda do
+ @nio.deregister io
+ @map.delete io
+ end
+ wakeup
+ end
+
+ def stop
+ @stopping = true
+ wakeup if @nio
+ end
+
+ private
+ def spawn
+ return if @thread && @thread.status
+
+ @spawn_mutex.synchronize do
+ return if @thread && @thread.status
+
+ @nio ||= NIO::Selector.new
+ @thread = Thread.new { run }
+
+ return true
+ end
+ end
+
+ def wakeup
+ spawn || @nio.wakeup
+ end
+
+ def run
+ loop do
+ if @stopping
+ @nio.close
+ break
+ end
+
+ until @todo.empty?
+ @todo.pop(true).call
+ end
+
+ next unless monitors = @nio.select
+
+ monitors.each do |monitor|
+ io = monitor.io
+ stream = @map[io]
+
+ begin
+ stream.receive io.read_nonblock(4096)
+ rescue IO::WaitReadable
+ next
+ rescue
+ # We expect one of EOFError or Errno::ECONNRESET in
+ # normal operation (when the client goes away). But if
+ # anything else goes wrong, this is still the best way
+ # to handle it.
+ begin
+ stream.close
+ rescue
+ @nio.deregister io
+ @map.delete io
+ end
+ end
+ end
+ end
+ end
+ end
+ end
+end