Book Image

Mastering Flask Web Development - Second Edition

By : Daniel Gaspar, Jack Stouffer
Book Image

Mastering Flask Web Development - Second Edition

By: Daniel Gaspar, Jack Stouffer

Overview of this book

Flask is a popular Python framework known for its lightweight and modular design. Mastering Flask Web Development will take you on a complete tour of the Flask environment and teach you how to build a production-ready application. You'll begin by learning about the installation of Flask and basic concepts such as MVC and accessing a database using an ORM. You will learn how to structure your application so that it can scale to any size with the help of Flask Blueprints. You'll then learn how to use Jinja2 templates with a high level of expertise. You will also learn how to develop with SQL or NoSQL databases, and how to develop REST APIs and JWT authentication. Next, you'll move on to build role-based access security and authentication using LDAP, OAuth, OpenID, and database. Also learn how to create asynchronous tasks that can scale to any load using Celery and RabbitMQ or Redis. You will also be introduced to a wide range of Flask extensions to leverage technologies such as cache, localization, and debugging. You will learn how to build your own Flask extensions, how to write tests, and how to get test coverage reports. Finally, you will learn how to deploy your application on Heroku and AWS using various technologies, such as Docker, CloudFormation, and Elastic Beanstalk, and will also learn how to develop Jenkins pipelines to build, test, and deploy applications.
Table of Contents (15 chapters)

Test coverage

Now that our tests have been written, we have to know whether our code is sufficiently tested. The concept of test coverage, also known as code coverage, was invented to solve this issue. In any project, the test coverage represents what percentage of the code in the project was executed when the tests were run, and which lines were never run. This gives an idea of what parts of the project aren't being tested by our unit tests. To add coverage reports to our project, install the coverage library with pip, and make sure it's included in the requirements.txt:

    (venv)$ pip install coverage

The coverage library can be run as a command-line program that will run your test suite, and take its measurements while the tests are running:

    $ coverage run --source webapp --branch -m unittest discover

The --source flag tells coverage to only report on the test...