Book Image

Architecting Data-Intensive Applications

By : Anuj Kumar
Book Image

Architecting Data-Intensive Applications

By: Anuj Kumar

Overview of this book

<p>Are you an architect or a developer who looks at your own applications gingerly while browsing through Facebook and applauding it silently for its data-intensive, yet ?uent and efficient, behaviour? This book is your gateway to build smart data-intensive systems by incorporating the core data-intensive architectural principles, patterns, and techniques directly into your application architecture.</p> <p>This book starts by taking you through the primary design challenges involved with architecting data-intensive applications. You will learn how to implement data curation and data dissemination, depending on the volume of your data. You will then implement your application architecture one step at a time. You will get to grips with implementing the correct message delivery protocols and creating a data layer that doesn’t fail when running high traffic. This book will show you how you can divide your application into layers, each of which adheres to the single responsibility principle. By the end of this book, you will learn to streamline your thoughts and make the right choice in terms of technologies and architectural principles based on the problem at hand.</p>
Table of Contents (18 chapters)
Title Page
Packt Upsell
Contributors
Preface
Index

Alternate Exchanges


Apart from user-defined exchanges, each cluster of RabbitMQ will define an Alternate Exchange.

Alternate Exchanges are very useful in scenarios where you need to handle orphan messages:

I get messages in my exchange that my exchange is unable to route. This may be because the queue is not available (yet), or the message was accidently published. How should I handle these kind of messages?

In data Bus, we will specify the Alternate Exchange using policies. The Alternate Exchange will be of the Topic Exchange type and will be attached to each of the underlying Exchanges. This will keep things consistent and the client doesn't have to worry about messages that need to be handled by Alternate Exchange.

In addition, there will be queues listening on this exchange based on the routing information.

 

Here is the diagrammatic representation of the Alternate Exchange and how it is used: