[feature] Same topic support multiple handlers

[navono]

[feature] Same topic support multiple handlers

[mustafaturan]

You can register as many handler as you want: https://godoc.org/github.com/mustafaturan/bus#Bus.RegisterHandler

[navono]

Maybe I didn't describe it clearly.

As the bus-sample-project, if modity counter.go file like this:

// Start registers the counter handler
func Start(wg *sync.WaitGroup) {
	b := config.Bus
	h := bus.Handler{Handle: count, Matcher: ".*"}
	b.RegisterHandler(worker, &h)
	fmt.Printf("Registered counter handler...\n")
	
	
	h2 := bus.Handler{Handle: count2, Matcher: ".*"}
	b.RegisterHandler(worker, &h2)
	
	wg.Add(1)
	go increment(wg)
}

count handler will not be called anymore because of

handlers map[string]*Handler

is not a list, it will replace with after new one.

[mustafaturan]

What do you think not to use the same name for the handlers. Instead of passing the first arg as ‘worker’ to both, you can use any different name. ‘name’ should be unique per handler and it is not a topic name

[navono]

Imagine a scenario where an http service receives a user request. After the service receives the request, it needs to send the same request message to a different service module for processing. At this time, it is different processing for the same topic name, instead of creating two different names.

[mustafaturan]

I am not sure if I understand correctly but I think you are trying register the handler dynamically on run time for each http request. If this is correct here is my suggestion:

• Handlers should be registered once the app runs then they should listen for events for performance reasons.
• If a handler needs to handle http request, the data can be passed with both of the context and event.Data to distinguish context specific logic.
• If you need dynamic handlers then the way is to provide a unique naming on handlers (not for the topics).
• Handler name and topic names are different concepts. Topic names are not coupled to handler names and handlers names are not coupled to topic names.