Book Image

Python Microservices Development

Book Image

Python Microservices Development

Overview of this book

We often deploy our web applications into the cloud, and our code needs to interact with many third-party services. An efficient way to build applications to do this is through microservices architecture. But, in practice, it's hard to get this right due to the complexity of all the pieces interacting with each other. This book will teach you how to overcome these issues and craft applications that are built as small standard units, using all the proven best practices and avoiding the usual traps. It's a practical book: you’ll build everything using Python 3 and its amazing tooling ecosystem. You will understand the principles of TDD and apply them. You will use Flask, Tox, and other tools to build your services using best practices. You will learn how to secure connections between services, and how to script Nginx using Lua to build web application firewall features such as rate limiting. You will also familiarize yourself with Docker’s role in microservices, and use Docker containers, CoreOS, and Amazon Web Services to deploy your services. This book will take you on a journey, ending with the creation of a complete Python application based on microservices. By the end of the book, you will be well versed with the fundamentals of building, designing, testing, and deploying your Python microservices.
Table of Contents (20 chapters)
Title Page
Credits
About the Author
About the Reviewer
www.PacktPub.com
Customer Feedback
Preface
Introduction

The full stack - OpenResty, Circus and Flask


When you release microservices as Docker images, there are two strategies for including a web server.

The first one consists of ignoring it and exposing the Flask application directly. A web server like OpenResty could then run in its docker container, proxying calls to your Flask container.

However, if you are using some power features in nginx, like a Lua-based application firewall as we have seen in Chapter 7, Securing Your Services, it can be better to include everything within the same container, together with a dedicated process manager.

In the diagram that follows, the docker container implements the second strategy, and runs both the web server and the Flask service. Circus is used to launch and watch one nginx process and a few Flask processes:

In this section, we will implement this container by adding in our Dockerfile the following steps:

  1. Download, compile, and install OpenResty.
  2. Add an nginx configuration file.
  3. Download and install Circus...