Book Image

Learning RabbitMQ

By : Martin Toshev
Book Image

Learning RabbitMQ

By: Martin Toshev

Overview of this book

RabbitMQ is Open Source Message Queuing software based on the Advanced Message Queue Protocol Standard written in the Erlang Language. RabbitMQ is an ideal candidate for large-scale projects ranging from e-commerce and finance to Big Data and social networking because of its ease of use and high performance. Managing RabbitMQ in such a dynamic environment can be a challenging task that requires a good understanding not only of how to work properly with the message broker but also of its best practices and pitfalls. Learning RabbitMQ starts with a concise description of messaging solutions and patterns, then moves on to concrete practical scenarios for publishing and subscribing to the broker along with basic administration. This knowledge is further expanded by exploring how to establish clustering and high availability at the level of the message broker and how to integrate RabbitMQ with a number of technologies such as Spring, and enterprise service bus solutions such as MuleESB and WSO2. We will look at advanced topics such as performance tuning, secure messaging, and the internals of RabbitMQ. Finally we will work through case-studies so that we can see RabbitMQ in action and, if something goes wrong, we'll learn to resolve it in the Troubleshooting section.
Table of Contents (18 chapters)
Learning RabbitMQ
Credits
About the Author
About the Reviewers
www.PacktPub.com
Preface
Index

Request-reply communication


The following diagram provides an overview of the scenario that we will implement:

The sender will send a message to the default exchange with a routing key that matches the name of the designated request queue. The request receiver is a subscriber to the request queue. After a request message is received, the request receiver retrieves the value of the replyTo property from the message header, creates a response message, and sends it to the default exchange with a routing key that matches the replyTo property. This means that the replyTo property points to a queue that handles response messages and the sender is subscribed to that queue in order to receive a response.

Let's extend our Sender class with the following sendRequest() method, which sends a message to the request_exchange exchange, and the receiveResponse() method, which receives a message from the response_queue queue as follows:

private static final String REQUEST_QUEUE = "request_queue";
private static...