Eventception
Eventception is a lightweight and simple Ruby Event System inspired on Symfony Event Dispatcher.
How to Install
Add the following to your Gemfile
:
gem 'eventception', '~> 0.1.0'
How to use
You can also read the documentation.
Events
When an event is dispatched, it's identified by a unique name, which any number of listeners might be listening to. An Event instance is also created and passed to all of the listeners. As you'll see later, the Event object itself often contains data about the event being dispatched.
The Dispatcher
The dispatcher is the central object of the event dispatcher system. In general, a single dispatcher is created, which maintains a registry of listeners. When an event is dispatched via the dispatcher, it notifies all listeners registered with that event:
require 'eventception'
dispatcher = Eventception::Dispatcher.new
Adding Listeners
require 'eventception'
class TodoListener
def on_creation(event)
puts "created a new to-do with title: '#{event.todo.title}'"
end
end
listener = TodoListener.new
dispatcher.add_listener(
event_name: 'todo.created',
listener: listener,
listener_method: 'on_creation'
)
Creating and Dispatching an Event
Creating the Event
require 'eventception'
class TodoCreatedEvent < Eventception::Event
NAME = 'todo.created'.freeze
attr_reader :todo
def initialize(todo)
@todo = todo
end
end
Dispatching the Event
class Todo
attr_reader :title
def initialize(title:)
@title = title
end
end
todo = Todo.new('My To-do')
event = TodoCreatedEvent.new(todo)
dispatcher.dispatch(TodoCreatedEvent::NAME, event)
# STDOUT: created a new to-do with title: 'My To-do'
LICENSE
Licensed under GNU LGPLv3
Contributing
- Fork it
- Create your feature branch (git checkout -b my-new-feature)
- Commit your changes (git commit -am 'Add some feature')
- Push to the branch (git push origin my-new-feature)
- Create new Pull Request