Rabbus 🚌 ✨

• A tiny wrapper over amqp exchanges and queues.
• In memory retries with exponential backoff for sending messages.
• Protect producer calls with circuit breaker.
• Automatic reconnect to RabbitMQ broker when connection is lost.
• Go channel API.

Installation

go get -u github.com/rafaeljesus/rabbus

Usage

The rabbus package exposes an interface for emitting and listening RabbitMQ messages.

Emit

import (
	"context"
	"time"

	"github.com/rafaeljesus/rabbus"
)

func main() {
	timeout := time.After(time.Second * 3)
	cbStateChangeFunc := func(name, from, to string) {
		// do something when state is changed
	}
	r, err := rabbus.New(
		rabbusDsn,
		rabbus.Durable(true),
		rabbus.Attempts(5),
		rabbus.Sleep(time.Second*2),
		rabbus.Threshold(3),
		rabbus.OnStateChange(cbStateChangeFunc),
	)
	if err != nil {
		// handle error
	}

	defer func(r Rabbus) {
		if err := r.Close(); err != nil {
			// handle error
		}
	}(r)

	ctx, cancel := context.WithCancel(context.Background())
	defer cancel()

	go r.Run(ctx)

	msg := rabbus.Message{
		Exchange: "test_ex",
		Kind:     "topic",
		Key:      "test_key",
		Payload:  []byte(`foo`),
	}

	r.EmitAsync() <- msg

	for {
		select {
		case <-r.EmitOk():
			// message was sent
		case <-r.EmitErr():
			// failed to send message
		case <-timeout:
			// handle timeout error
		}
	}
}

Listen

import (
	"context"
	"encoding/json"
	"time"

	"github.com/rafaeljesus/rabbus"
)

func main() {
	timeout := time.After(time.Second * 3)
	cbStateChangeFunc := func(name, from, to string) {
		// do something when state is changed
	}
	r, err := rabbus.New(
		rabbusDsn,
		rabbus.Durable(true),
		rabbus.Attempts(5),
		rabbus.Sleep(time.Second*2),
		rabbus.Threshold(3),
		rabbus.OnStateChange(cbStateChangeFunc),
	)
	if err != nil {
		// handle error
	}

	defer func(r Rabbus) {
		if err := r.Close(); err != nil {
			// handle error
		}
	}(r)

	ctx, cancel := context.WithCancel(context.Background())
	defer cancel()

	go r.Run(ctx)

	messages, err := r.Listen(rabbus.ListenConfig{
		Exchange:    "events_ex",
		Kind:        "topic",
		Key:         "events_key",
		Queue:       "events_q",
		DeclareArgs: rabbus.NewDeclareArgs().WithMessageTTL(15 * time.Minute).With("foo", "bar"),
		BindArgs:    rabbus.NewBindArgs().With("baz", "qux"),
	})
	if err != nil {
		// handle errors during adding listener
	}
	defer close(messages)

	go func(messages chan ConsumerMessage) {
		for m := range messages {
			m.Ack(false)
		}
	}(messages)
}

Contributing

• Fork it
• Create your feature branch (git checkout -b my-new-feature)
• Commit your changes (git commit -am 'Add some feature')
• Push to the branch (git push origin my-new-feature)
• Create new Pull Request

Badges

GitHub @rafaeljesus  ·  Medium @_jesus_rafael  ·  Twitter @_jesus_rafael