Good way to organize Pub/Sub subjects for both publishers and consumers. Can be applied to other OOP languages as well.

subjects.go

package api

import "fmt"

func publish(subject string) {
	fmt.Println("Publishing on", subject)
}

func subscribe(subject string) {
	fmt.Println("Subscribing on", subject)
}

func example() {
	var subjects Subjects
	publish(subjects.NoteByID("123"))
	publish(subjects.NoteCreate())
	subscribe(subjects.NoteUpdate("*"))
	subscribe(subjects.Time("eu", "ljubljana"))
}

// Subjects builds subjects.
// Wildcards can be passed as parameters.
type Subjects struct{}

func (Subjects) NoteList() string {
	return "note.list"
}

func (Subjects) NoteByID(id string) string {
	return "note.by_id." + id
}

func (Subjects) NoteCreate() string {
	return "note.create"
}

func (Subjects) NoteUpdate(id string) string {
	return "note.update." + id
}

func (Subjects) NoteDelete(id string) string {
	return "note.delete." + id
}

// Example from https://docs.nats.io/nats-concepts/subjects

func (Subjects) Time(region, city string) string {
	return "time." + region + "." + city
}