module Rainbows::EventMachine
Implements a basic single-threaded event model with EventMachine. It is capable of handling thousands of simultaneous client connections, but with only a single-threaded app dispatch. It is suited for slow clients, and can work with slow applications via asynchronous libraries such as async_sinatra, Cramp, and rack-fiber_pool.
It does not require your Rack application to be thread-safe, reentrancy is only required for the DevFdResponse
body generator.
Compatibility: Whatever EventMachine ~> 0.12.10 and Unicorn
both support, currently Ruby 1.8/1.9.
This model is compatible with users of “async.callback” in the Rack environment such as async_sinatra.
For a complete asynchronous framework, Cramp is fully supported when using this concurrency model.
This model is fully-compatible with rack-fiber_pool which allows each request to run inside its own Fiber after all request processing is complete.
Merb (and other frameworks/apps) supporting deferred?
execution as documented at Rainbows::EventMachine::TryDefer
This model does not implement as streaming “rack.input” which allows the Rack application to process data as it arrives. This means “rack.input” will be fully buffered in memory or to a temporary file before the application is entered.
RubyGem Requirements¶ ↑
-
event_machine 0.12.10
Public Instance Methods
# File lib/rainbows/event_machine.rb, line 67 def defers_finished? # EventMachine 1.0.0+ has defers_finished? EM.respond_to?(:defers_finished?) ? EM.defers_finished? : true end
Cramp (and possibly others) can subclass Rainbows::EventMachine::Client and provide the :em_client_class option. We /don't/ want to load Rainbows::EventMachine::Client in the master process since we need reloadability.
# File lib/rainbows/event_machine.rb, line 56 def em_client_class case klass = Rainbows::O[:em_client_class] when Proc klass.call # e.g.: proc { Cramp::WebSocket::Rainbows } when Symbol, String eval(klass.to_s) # Object.const_get won't resolve multi-level paths else # @use should be either :EventMachine or :NeverBlock Rainbows.const_get(@use).const_get(:Client) end end