Event

Lightweight event management, dispatch tool library implemented by Go

• Support for custom definition event objects
• Support for adding multiple listeners to an event
• Supports setting the priority of the event listener. The higher the priority, the higher the trigger.
• Support for a set of event listeners based on the event name prefix PREFIX.*.
  • add app.* event listen, trigger app.run app.end, Both will trigger the app.* event at the same time
• Support for using the wildcard * to listen for triggers for all events
• Complete unit testing, unit coverage > 95%

中文说明

中文说明请看 README.zh-CN

GoDoc

• Godoc for github

Main method

• On/Listen(name string, listener Listener, priority ...int) Register event listener
• Subscribe/AddSubscriber(sbr Subscriber) Subscribe to support registration of multiple event listeners
• Trigger/Fire(name string, params M) (error, Event) Trigger event
• MustTrigger/MustFire(name string, params M) Event Trigger event, there will be panic if there is an error
• FireEvent(e Event) (err error) Trigger an event based on a given event instance
• FireBatch(es ...interface{}) (ers []error) Trigger multiple events at once
• AsyncFire(e Event) Async fire event by 'go' keywords

Quick start

package main

import (
	"fmt"
	
	"github.com/gookit/event"
)

func main() {
	// Register event listener
	event.On("evt1", event.ListenerFunc(func(e event.Event) error {
        fmt.Printf("handle event: %s\n", e.Name())
        return nil
    }), event.Normal)
	
	// Register multiple listeners
	event.On("evt1", event.ListenerFunc(func(e event.Event) error {
        fmt.Printf("handle event: %s\n", e.Name())
        return nil
    }), event.High)
	
	// ... ...
	
	// Trigger event
	// Note: The second listener has a higher priority, so it will be executed first.
	event.MustFire("evt1", event.M{"arg0": "val0", "arg1": "val1"})
}

Write event listeners

Using anonymous functions

package mypgk

import (
	"fmt"
	
	"github.com/gookit/event"
)

var fnHandler = func(e event.Event) error {
	fmt.Printf("handle event: %s\n", e.Name())
    return nil
}

func Run() {
    // register
    event.On("evt1", event.ListenerFunc(fnHandler), event.High)
}

Using the structure method

interface:

// Listener interface
type Listener interface {
	Handle(e Event) error
}

example:

Implementation interface event.Listener

package mypgk

import (
	"fmt"
	"github.com/gookit/event"
)

type MyListener struct {
	// userData string
}

func (l *MyListener) Handle(e event.Event) error {
	e.Set("result", "OK")
	return nil
}

Register multiple event listeners

interface:

// Subscriber event subscriber interface.
// you can register multi event listeners in a struct func.
type Subscriber interface {
	// SubscribedEvents register event listeners
	// key: is event name
	// value: can be Listener or ListenerItem interface
	SubscribedEvents() map[string]interface{}
}

example

Implementation interface event.Subscriber

package mypgk

import (
	"fmt"
	
	"github.com/gookit/event"
)

type MySubscriber struct {
	// ooo
}

func (s *MySubscriber) SubscribedEvents() map[string]interface{} {
	return map[string]interface{}{
		"e1": event.ListenerFunc(s.e1Handler),
		"e2": event.ListenerItem{
			Priority: event.AboveNormal,
			Listener: event.ListenerFunc(func(e Event) error {
				return fmt.Errorf("an error")
			}),
		},
		"e3": &MyListener{},
	}
}

func (s *MySubscriber) e1Handler(e event.Event) error {
	e.Set("e1-key", "val1")
	return nil
}

Write custom events

interface:

// Event interface
type Event interface {
	Name() string
	// Target() interface{}
	Get(key string) interface{}
	Add(key string, val interface{})
	Set(key string, val interface{})
	Data() map[string]interface{}
	SetData(M) Event
	Abort(bool)
	IsAborted() bool
}

examples:

package mypgk 

import (
	"fmt"
	
	"github.com/gookit/event"
)

type MyEvent struct{
	event.BasicEvent
	customData string
}

func (e *MyEvent) CustomData() string {
    return e.customData
}

Usage:

e := &MyEvent{customData: "hello"}
e.SetName("e1")
event.AddEvent(e)

// add listener
event.On("e1", event.ListenerFunc(func(e event.Event) error {
   fmt.Printf("custom Data: %s\n", e.(*MyEvent).CustomData())
   return nil
}))

// trigger
event.Fire("e1", nil)
// OR
// event.FireEvent(e)

Gookit packages

• gookit/ini Go config management, use INI files
• gookit/rux Simple and fast request router for golang HTTP
• gookit/gcli build CLI application, tool library, running CLI commands
• gookit/slog Lightweight, extensible, configurable logging library written in Go
• gookit/event Lightweight event manager and dispatcher implements by Go
• gookit/cache Generic cache use and cache manager for golang. support File, Memory, Redis, Memcached.
• gookit/config Go config management. support JSON, YAML, TOML, INI, HCL, ENV and Flags
• gookit/color A command-line color library with true color support, universal API methods and Windows support
• gookit/filter Provide filtering, sanitizing, and conversion of golang data
• gookit/validate Use for data validation and filtering. support Map, Struct, Form data
• gookit/goutil Some utils for the Go: string, array/slice, map, format, cli, env, filesystem, test and more
• More please see https://github.com/gookit

LICENSE

MIT