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

Asynchronous versus synchronous


Switching to an asynchronous model means you will need to use asynchronous code all the way down.

For example, if your microservice uses a Requests library that is not asynchronous, every call made to query an HTTP endpoint will block the event loop, and you will not benefit from asynchronicity.

And making an existing project asynchronous is not an easy task because it changes the design completely. Most projects that want to support asynchronous calls are redesigning everything from scratch.

Note

The good news is that there are more and more asynchronous libraries available, which can be used to build a microservice. On PyPI, you can search for aio or asyncio. This wiki page (https://github.com/python/asyncio/wiki/ThirdParty) is also a good place to look at.

Here's a short list of those that are relevant to building microservices:

  • aiohttp.Client: ;Can replace the requests package
  • aiopg: ;PostgreSQL driver on top of Psycopg
  • aiobotocore: ;AWS client--might be merged...