Book Image

Microservices Development Cookbook

By : Paul Osman
Book Image

Microservices Development Cookbook

By: Paul Osman

Overview of this book

Microservices have become a popular choice for building distributed systems that power modern web and mobile apps. They enable you to deploy apps as a suite of independently deployable, modular, and scalable services. With over 70 practical, self-contained tutorials, the book examines common pain points during development and best practices for creating distributed microservices. Each recipe addresses a specific problem and offers a proven, best-practice solution with insights into how it works, so you can copy the code and configuration files and modify them for your own needs. You’ll start by understanding microservice architecture. Next, you'll learn to transition from a traditional monolithic app to a suite of small services that interact to ensure your client apps are running seamlessly. The book will then guide you through the patterns you can use to organize services, so you can optimize request handling and processing. In addition this, you’ll understand how to handle service-to-service interactions. As you progress, you’ll get up to speed with securing microservices and adding monitoring to debug problems. Finally, you’ll cover fault-tolerance and reliability patterns that help you use microservices to isolate failures in your apps. By the end of this book, you’ll have the skills you need to work with a team to break a large, monolithic codebase into independently deployable and scalable microservices.
Table of Contents (16 chapters)
Title Page
Copyright and Credits
Packt Upsell
Contributors
Preface
Index

Authenticating your microservices


In Chapter 1, Breaking the Monolith, we introduced a Ruby on Rails code base that powers our fictional image-sharing application, pichat. The Rails code base authenticates each request by inspecting the Authorization header. If the header is present, the application attempts to decode it using a shared secret read from an environment variable(seethe Secure configuration recipe). If the token provided in the Authorization header is valid, the decoded value contains contextual information about the user, including the user ID. That information is then used to retrieve the user from the database so that the application has context on the user making the request. If the Authorization header is missing or cannot be decoded successfully, the application raises an exception and returns an HTTP 401 to the caller, including an error message. In order to obtain a token to include in the Authorization header, a client application can send a POST request to the /auth...