GoMQ

An In-memory message broker in Golang.

Introduction

Gomq is an in-memory message broker. The behaviour is similar to rabbitmq. Hence provides subscription to topics based on pattern match.

Gomq being a message broker it is thread safe and is Interface based. Thereby allowing easy testing.

Currently supports Go 1.15+.

Installation

go get github.com/RohanPoojary/gomq

TODO

• Optimise Publish.

Topics

Creating a Broker

import (
	"github.com/RohanPoojary/gomq"
)

func main() {
	broker := gomq.NewBroker()
        ...
}

Subscribing to a Topic

You can subscribe to a topic both on exact & regex matcher.

Exact Match

    
    broker := gomq.NewBroker()

    // Subscribes to "users" topic.
    usersPoller := broker.Subscribe(gomq.ExactMatcher("users"))

Regex Match

    
    broker := gomq.NewBroker()

    // Subscribes to any topic that matches "users.*" .
    usersPoller := broker.Subscribe(regexp.MustCompile(`users\.\w*`))

Publishing to a Topic

    
    broker := gomq.NewBroker()

    broker.Publish("users.id", 100)

Reading from a Subscriber

    
    broker := gomq.NewBroker()
    defer broker.Close(0)

    usersPoller := broker.Subscribe(regexp.MustCompile(`users\.\w*`))
    
    go func() {
        for {
            // Poll is a blocking call. Hence wrapped into a different routine.
            value, ok := usersPoller.Poll()
            if !ok {
                return
            }
    
            userID := value.(int)
            // Do Something
        }
    }()

Benchmark

The benchmark is done on Publish (publishes the message) & Poll (polls the message from queue). In all benchmarks both publisher & subscriber are present at any point of time.

Point to note is that the broker is optimized around Poll, Hence publish slows with more number of Consumers, while the Poll doesn't slow at the same rate.

>  go test -cpu 4 -bench .
goos: darwin
goarch: amd64
pkg: github.com/RohanPoojary/gomq
BenchmarkPublish/Consumers=1-4         	                     1000000	      1178 ns/op
BenchmarkPublish/Consumers=10-4        	                      300000	      4504 ns/op
BenchmarkPublish/Consumers=30-4        	                      200000	     11523 ns/op
BenchmarkPublish/Consumers=50-4        	                      100000	     19384 ns/op
BenchmarkConsume/Publisher=1-4         	                     1000000	      1599 ns/op
BenchmarkConsume/Publisher=10-4        	                     1000000	      1788 ns/op
BenchmarkConsume/Publisher=30-4        	                     1000000	      2182 ns/op
BenchmarkConsume/Publisher=50-4        	                     1000000	      2330 ns/op
BenchmarkMultiConsume/Publisher=50/Consumer=10-4         	 1000000	      1134 ns/op
BenchmarkMultiConsume/Publisher=50/Consumer=30-4         	  500000	      3568 ns/op
BenchmarkMultiConsume/Publisher=50/Consumer=50-4         	  500000	      4416 ns/op
PASS

Contribution

Feel free to contribute or request any feature. Reporting issues can also help.