README.md in faye-rails-1.0.3 vs README.md in faye-rails-1.0.4
- old
+ new
@@ -4,62 +4,74 @@
# Embedded server
Due to the limitations of most Rack-based web servers available Faye can only be run on Thin, however if you are using thin, then you can add as many Faye servers as you want to the Rails router like so:
- App::Application.routes.draw do
- faye_server '/faye', :timeout => 25
- end
+```ruby
+App::Application.routes.draw do
+ faye_server '/faye', :timeout => 25
+end
+```
You can also pass a block to `faye_server` which will be executed in the context of the Faye server, thus you can call any methods on `Faye::RackAdapter` from within the block:
- App::Application.routes.draw do
- faye_server '/faye', :timeout => 25 do
- class MockExtension
- def incoming(message, callback)
- callback.call(message)
- end
- end
- add_extension(MockExtension.new)
+```ruby
+App::Application.routes.draw do
+ faye_server '/faye', :timeout => 25 do
+ class MockExtension
+ def incoming(message, callback)
+ callback.call(message)
end
end
+ add_extension(MockExtension.new)
+ end
+end
+```
If you really want to, you can ask Faye to start it's own listening Thin server on an arbitrary port:
- App::Application.routes.draw do
- faye_server '/faye', :timeout => 25 do
- listen(9292)
- end
- end
+```ruby
+App::Application.routes.draw do
+ faye_server '/faye', :timeout => 25 do
+ listen(9292)
+ end
+end
+```
You can also do some rudimentary routing using the map method:
- App::Application.routes.draw do
- faye_server '/faye', :timeout => 25 do
- map '/widgets/**' => WidgetsController
- map :default => :block
- end
- end
+```ruby
+App::Application.routes.draw do
+ faye_server '/faye', :timeout => 25 do
+ map '/widgets/**' => WidgetsController
+ map :default => :block
+ end
+end
+```
You can find more details on the #map method in the [rdoc](http://rubydoc.info/github/jamesotron/faye-rails/master/FayeRails/RackAdapter)
# Controller
faye-rails includes a controller for handling the binding between model events and channels with it's own DSL for managing channel-based events.
- class WidgetController < FayeRails::Controller
- end
+```ruby
+class WidgetController < FayeRails::Controller
+end
+```
## Model observers
You can subscribe to changes in models using the controller's observer DSL:
- class WidgetController < FayeRails::Controller
- observe Widget, :after_create do |new_widget|
- WidgetController.publish('/widgets', new_widget.attributes)
- end
- end
+```ruby
+class WidgetController < FayeRails::Controller
+ observe Widget, :after_create do |new_widget|
+ WidgetController.publish('/widgets', new_widget.attributes)
+ end
+end
+```
The available callbacks are derived from the ActiveRecord callback stack. See [ActiveRecord::Callbacks](http://api.rubyonrails.org/classes/ActiveRecord/Callbacks.html) for more information regarding the callback queue.
See the [rdoc](http://rubydoc.info/github/jamesotron/faye-rails/master/FayeRails/Controller.observe) for more information.
@@ -69,49 +81,67 @@
### Monitoring
You can make use of Faye's [monitoring API](http://faye.jcoglan.com/ruby/monitoring.html) by adding calls to `monitor` within the channel block. You are able to monitor `:subscribe`, `:unsubscribe` and `:publish` events. Blocks are executed within the context of a `FayeRails::Controller::Monitor` instance which will give you access to `#client_id`, `#channel` and `#data` (`#data` only having a value on `:publish` events).
- class WidgetController < FayeRails::Controller
- channel '/widgets' do
- monitor :subscribe do
- puts "Client #{client_id} subscribed to #{channel}."
- end
- monitor :unsubscribe do
- puts "Client #{client_id} unsubscribed from #{channel}."
- end
- monitor :publish do
- puts "Client #{client_id} published #{data.inspect} to #{channel}."
- end
- end
+```ruby
+class WidgetController < FayeRails::Controller
+ channel '/widgets' do
+ monitor :subscribe do
+ puts "Client #{client_id} subscribed to #{channel}."
end
+ monitor :unsubscribe do
+ puts "Client #{client_id} unsubscribed from #{channel}."
+ end
+ monitor :publish do
+ puts "Client #{client_id} published #{data.inspect} to #{channel}."
+ end
+ end
+end
+```
### Filtering
You can quickly and easily filter incoming and outgoing messages for your specific channel using the controller's filter API, which wraps Faye's [extensions API](http://faye.jcoglan.com/ruby/extensions.html) in a concise and channel-specific way.
- class WidgetController < FayeRails::Controller
- channel '/widgets' do
- filter :in do
- puts "Inbound message #{message}."
- pass
- end
- end
+```ruby
+class WidgetController < FayeRails::Controller
+ channel '/widgets' do
+ filter :in do
+ puts "Inbound message #{message}."
+ pass
end
+ end
+end
+```
You can add filters for `:in`, `:out` and `:any`, which will allow you to filter messages entering the server, exiting the server or both. The block passed to the `filter` is executed in the context of a `FayeRails::Filter::DSL` instance, which gives you access to the `#message` method, which contains the entire message payload from the client (including meta information you wouldn't see other ways). You also have access to the `#pass`, `#modify`, `#block` and `#drop` methods which are sugar around Faye's callback system - which is accessible via the `#callback` method if you want to do it that way. Check out the [FayeRails::Filter::DSL rdoc](http://rubydoc.info/github/jamesotron/faye-rails/master/FayeRails/Filter/DSL) for more information. Please note that all filters must call `callback.call` either via the sugar methods or directly to ensure that requests are not lost (not to mention potential memory leaks).
### Subscribing
You can easily subscribe to a channel using the 'subscribe' method inside your channel block, like so:
- class WidgetController < FayeRails::Controller
- channel '/widgets' do
- subscribe do
- puts "Received on channel #{channel}: #{message.inspect}"
- end
- end
+```ruby
+class WidgetController < FayeRails::Controller
+ channel '/widgets' do
+ subscribe do
+ puts "Received on channel #{channel}: #{message.inspect}"
end
+ end
+end
+```
+
+# Non-server environments
+
+Often you'll find yourself running the Rails environment without the server running - eg when doing background job processing, or running the console. If you have any actions which use Faye then you'll need to make sure that you have the EventMachine reactor running. The easiest solution to this is to create an initialiser in `config/initializers` which calls `Faye.ensure_reactor_running!`. For workers in production you probably also want to make sure that you are using the Redis engine for Faye to ensure that multiple server instances see the same data.
+
+```ruby
+App::Application.routes.draw do
+ faye_server '/faye', timeout: 25, engine: {type: Faye::Redis, host: 'localhost'} do
+ map '/announce/**' => SomeController
+ end
+end
+```
# Thanks.
Thanks to James Coglan for the excellent Faye Bayeux implementetation and great support for Faye users.