Introduction

This project contains multiple examples using the different RabbitMQ exchanges with Spring Boot 2.

Additionally, the project contains all the configuration files that are required to run in Heroku.

Examples

Default exchange (basic)

The default exchange is a direct exchange with no name. Every queue is automatically bound to the default exchange with a routing key which is the queue name.

Fanout exchange (broadcast)

The fanout exchange sends the message to all queues that are bound to it.

Direct exchange (direct)

The direct exchange sends the message to the queues that are bind to the exchange with the same routing key that is used to send the message.

Headers exchange (headers)

The headers exchange sends the message to the queues that are bind to the exchange with any/all of the headers of the message.

Te use of this type of exchange is not recommended if you can use the topic exchange, its performance is better.

Topic exchange (topic)

The topic exchange sends the message to the queues that are bind to the exchange with a routing pattern that match the routing key.

In this exchange the routing key is a list of words delimited by periods (.).

The routing patters consists of exact words, asterisks (*) to match a word and hashtags (#) to match zero or more words.

Exception handling

The default configuration for the unhandled exceptions is requeuing the message. We can change this in the properties (spring.rabbitmq.listener.simple.default-requeue-rejected).

Running it

Running locally

With docker compose

1. Select the example to run changing the value of the property app.rabbitmq.example in the file application-dev.properties. (Supported values are basic | broadcast | direct | headers | topic)
2. Run docker-compose up in the root folder.
3. Run mvnw spring-boot:run -Dspring-boot.run.profiles=producer,dev in the root folder to start a instance of the producer.
4. Run mvnw spring-boot:run -Dspring-boot.run.profiles=consumer,dev in the root folder to start a instance of the consumer.

You can enter in the the rabbit web console going to http://localhost:15672/ with the credentials guest:guest.

Without docker compose

1. Select the example to run changing the value of the property app.rabbitmq.example in the file application-dev.properties. (Supported values are basic | broadcast | direct | headers | topic)
2. Configure the properties of the RabbitMQ in the file application-dev.properties.
3. Run mvnw spring-boot:run -Dspring-boot.run.profiles=producer,dev in the root folder to start a instance of the producer.
4. Run mvnw spring-boot:run -Dspring-boot.run.profiles=consumer,dev in the root folder to start a instance of the consumer.

Running on Heroku

To run the example in Heroku, you need the CloudAMQP add-on.

The configuration is defined in the Procfile.

The env properties are:

Property	Definition	Default value
CLOUDAMQP_URL	RabbitMQ connection url, added by the add-on	-
EXAMPLE_TYPE	The example to run	basic
DELAY_MS	The delay between sends in milliseconds	10000