Simple and clean implementation of outbox.

Available storages:

• MongoDB
• Mysql (in progress)

Available broker/producer:

• Kafka

Create a collection on mongodb with this fields

{
  "idempotency_id": "58452f68-705b-4b2e-8685-fc929e750588",
  "message": {
    "id": "58452f68-705b-4b2e-8685-fc929e750588",
    "name": "Guilherme",
    "age": 27
  },
  "topic": "user_created"
}

Initialize outbox

mongoStorage := mongostorage.NewMongoStorage(mongoConnection())
kafkaProducer := kafka.NewProducer(kafka.NewProducer(
		&kafka.ConfigMap{
			"bootstrap.servers":        "localhost:29092",
			"delivery.timeout.ms":      600000,
			"linger.ms":                10000,
			"message.send.max.retries": 10000000,
			"batch.num.messages":       1,
			"enable.idempotence":       true,
		},
	))

o := outbox.NewOutbox(mongoStorage, kafkaProducer)

go o.Listen(context.Background())

In your storage layer do you should remember to use db transaction to save to your app collection/table and outbox.

Use the docker-compose inside example_mongo to up dependencies and run the example

It's recommend use the configuration batch.num.messages with value 1 to will don't have problem with duplicate messages, also validate idempotency_id on consumer