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A go package to send and receive pub-sub messages using channels.

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~ eventbus ~

A go package to send and receive pub-sub messages using channels.

     

go get -u github.com/zekrotja/eventbus

Intro

This package provides a very simple, generic pub-sub event bus to simplify sending event messages between services using channels.

Why using channels over callbacks?

Callback are - in my opinion - not a very clean and performant way to perform event driven development in Go because, in contrast to languages like JavaScript, Go is not an event driven language. This can lead to blocking publisher routines while waiting for the execution of callbacks on the side of subscribers. Channels, which are well designed to communicate between go routines in the first place, are therefore a way better tool to achieve easy, performant and intuitive communication of events between publishers and subscribers.

Basic Example

package main

import (
	"bufio"
	"fmt"
	"os"

	"github.com/zekrotja/eventbus"
)

func subscriber(name string, bus *eventbus.EventBus[string]) {
	c, _ := bus.Subscribe()
	for msg := range c {
		fmt.Printf("[ -> %s ]: %s\n", name, msg)
	}
}

func main() {
	s := bufio.NewScanner(os.Stdin)
	bus := eventbus.New[string]()

	go subscriber("service1", bus)
	go subscriber("service2", bus)

	bus.SubscribeFunc(func(s string) {
		if s == "exit" {
			os.Exit(0)
		}
	})

	fmt.Println("Publish messages by writing them to the console.\nPress CTRL+C or write 'exit' to exit.")
	for s.Scan() {
		bus.Publish(s.Text())
	}
}

Further examples can be found in the examples directory. If you want to take alook at a practical example, feel free to explore my project Yuri69 which heavily depends on EventBus.