An EventEmitter for Go

Build Status:

Install

With go get:

% go get github.com/CHH/eventemitter

Usage

For more information please also see the Package Docs.

A new EventEmitter is created by the New function.

import "github.com/CHH/eventemitter"

func main() {
    emitter := eventemitter.New()
}

A listener is of type func (event *ee.Event) Listeners can be bound to event names with the On method:

emitter.On("foo", func(name string) {
    fmt.Printf("Hello World %s", name)
})

An event can be triggered by calling the Emit method:

<- emitter.Emit("foo", "John")

When Emit is called, each registered listener is called in its own Goroutine. They all share a common channel, which is returned by the Emit function.

var c chan interface{} 

c = emitter.Emit("foo", "John")

This channel can be used to wait until all listeners have finished, by using the <- operator without variable:

<- emitter.Emit("foo", "John")

Each listener yields a reference to eventemitter.Response on the channel once it has finished:

c := emitter.Emit("foo", "John")

for resp := <- c {
    // Do something
}

Embedding

EventEmitters can also be embedded in other types. When embedding you've to call the Init function on the EventEmitter, so the memory is correctly allocated:

type Server struct {
    eventemitter.EventEmitter
}

func NewServer() *Server {
    s := new(Server)

    // Allocates the EventEmitter's memory.
    s.EventEmitter.Init()

    // All functions of the EventEmitter are available:
    s.On("foo", func() {
        
    })
}

License

EventEmitter is distributed under the Terms of the MIT License. See the bundled file LICENSE.txt for more information.