Go Example - Channel that can receive any type

generic_channel.go

package main

import (
	"log"
	"reflect"
)


/*
This is an example of a channel that can receive any data type, e.g. different struct types
It shows how to use switch on the type of the data received in the channel to allow you
to change the logic based on the type
It shows how to use close() to close the channel when no more values are sent to it and how to shutdown the go routine
based on the channel still being open (isOpen)

Output:
2017/04/27 08:39:38 TypeA
2017/04/27 08:39:38 main.TypeB
 */

func main(){

	ch := make(chan  interface{}) // channel to receive any type
	done := make(chan bool) //  channel to wait for completion

	// declare a couple of types
	type TypeA struct{
		A int
	}

	type TypeB struct{
		A int
	}

	// channel receiver
	go func () {
		for {
			d, isOpen := <-ch // get data off chanel
			switch d.(type) { // do different logic base on the type of the data
			case TypeA:
				log.Print("TypeA")
			case TypeB:
				log.Print(reflect.TypeOf(d))
			}
			if !isOpen { // if the channel has been closed, signal done and exit go routine
				done <- true
				return
			}
		}
	}()

	// send instances of different types
	ch <- TypeA{0}
	ch <- TypeB{0}
	close(ch) // close the channel as we are nto sending anything else

	<- done // wait for go routine to finish
}