goevent

goevent is an event emitter similar to javascript's custom events.

Note :

This is not a pattern you should have inside your code all over the place . You should use this package for specific use cases. Some of those use cases are listed below.

Use Case :

• Init / Shutdown events for your rest api
• Async Processing
• PUB->SUB Local events
• etc ...

Contents

• Installation
• Usage
  • Global
  • Local

Installation

go get github.com/baderkha/goevent

Usage

This section will cover exemplar scenarios for this package. This package can be used to emit global events you can subscribe to anywhere in the code , or local events if you want to manage / orchestrate the events.

Global

For Global Events you first need to init the global emitter as such

1. Init

   // somewhere in your main func
   func main() {
       // IF YOU DO NOT DO THIS , THIS WILL CRASH
   
       // choose to have your panics handled gracefully
       handlePanics := true 
       goevent.InitGlobal(handlePanics)
   }

2. Add Event Listener

   // somewhere else
   listenerHash := goevent.
           Global().
           AddListener("slim_shady", func(d interface{}) {
               name := d.(string)
               fmt.Println("BAND NAME => " + name)
           })

3. Emit Event

   // somewhere else
   goevent.
           Global().
           Emit("slim_shady","d12")
   
   // with the event emitted above this will  output
   // "BAND NAME => d12"

4. Remove Event Listener

   // somewhere else
   hasBeenRemoved := goevent.
          Global().
          RemoveListener(listenerHash)
   // will be false if it doesn't exist
   fmt.Println(hasBeenRemoved)

Local

For Local events you can construct them from any where and attach them to structs

1. Init

   // from anywhere
   
   
   handlePanics := true // choose to have your panics handled 
   
   // this object is local ie everytime you call new you get a new one
   ev := goevent.New(handlePanics) 

2. Add Event Listener

   listenerHash:= ev.AddListener("slim_shady", func(d interface{}) {
                   name := d.(string)
                   fmt.Println("BAND NAME => " + name)
               })

3. Emit Event

   ev.Emit("slim_shady","d12")

4. Remove Event Listener

   ev.RemoveListener(listenerHash)