xgfone / go-event

A simple event emmiter for Go. Inspired by Nodejs EventEmitter(https://nodejs.org/api/events.html)

go-event

A simple event emmiter for Go 1.5+. Inspired by Nodejs EventEmitter.

Installation

$ go get -u github.com/xgfone/go-event

Example

package main

import (
	"fmt"
	"sort"

	"github.com/xgfone/go-event"
)

func main() {
	newListener := func(listenerName string) event.ListenerFunc {
		return func(event string, data ...interface{}) {
			fmt.Printf("listener=%s, event=%s, data=%v\n", listenerName, event, data)
		}
	}

	ln1 := newListener("ln1")
	ln2 := newListener("ln2")
	ln3 := newListener("ln3")

	event.On("e1", "ln1", ln1)
	event.On("e1", "ln2", ln2)
	event.OnFunc("e2", "ln2", ln2)
	event.OnFunc("e2", "ln3", ln3)
	event.OnFunc("e3", "ln3", ln3)
	event.OnceFunc("e3", "ln1", ln1) // Only trigger once


	events := event.Events()
	sort.Strings(events)
	fmt.Printf("Events: %v\n", events)

	event.Emit("e1", "data1")
	event.Emit("e2", "data2")
	event.Emit("e3", "data3")

	event.Off("e1", "ln1")
	event.Off("e2", "ln2")
	event.Off("e3", "ln3")

	events = event.Events()
	sort.Strings(events)
	fmt.Printf("Events: %v\n", events)

	event.Emit("e1", "data4")
	event.Emit("e2", "data5")
	event.Emit("e3", "data6")

	event.EmitAsync("e1", "data7").Wait()
	event.EmitAsync("e2", "data8").Wait()
	event.EmitAsync("e3", "data9").Wait()

	// Remove the event "e2" and all its listeners.
	event.Off("e2", "")

	events = event.Events()
	sort.Strings(events)
	fmt.Printf("Events: %v\n", events)

	// Remove all the events and their listeners.
	event.Off("", "")

	events = event.Events()
	sort.Strings(events)
	fmt.Printf("Events: %v\n", events)

	// Output:
	// Events: [e1 e2 e3]
	// listener=ln1, event=e1, data=[data1]
	// listener=ln2, event=e1, data=[data1]
	// listener=ln2, event=e2, data=[data2]
	// listener=ln3, event=e2, data=[data2]
	// listener=ln3, event=e3, data=[data3]
	// listener=ln1, event=e3, data=[data3]
	// Events: [e1 e2]
	// listener=ln2, event=e1, data=[data4]
	// listener=ln3, event=e2, data=[data5]
	// listener=ln2, event=e1, data=[data7]
	// listener=ln3, event=e2, data=[data8]
	// Events: [e1]
	// Events: []
}