Welcome to Flask — Flask Documentation (3.1.x)
Flask provides configuration and conventions, with sensible defaults, to get started. This section of the documentation explains the different parts of the Flask framework and how they can be used, customized, and extended.
Installation — Flask Documentation (3.1.x)
Flask is now installed. Check out the Quickstart or go to the Documentation Overview.
Tutorial — Flask Documentation (3.1.x)
Check out the Quickstart for an overview of what Flask can do, then dive into the docs to find out more. The tutorial only uses what’s provided by Flask and Python.
Quickstart — Flask Documentation (3.1.x)
Flask provides a really simple way to give feedback to a user with the flashing system. The flashing system basically makes it possible to record a message at the end of a request and access it on the next (and only the next) request.
Using async and await — Flask Documentation (3.1.x)
Traditional Flask views will still be appropriate for most use cases, but Flask’s async support enables writing and using code that wasn’t possible natively before.
API — Flask Documentation (3.1.x)
Flask parses incoming request data for you and gives you access to it through that global object. Internally Flask makes sure that you always get the correct data for the active thread if you are in a multithreaded environment.
Application Structure and Lifecycle — Flask Documentation (3.1.x)
The first step in creating a Flask application is creating the application object. Each Flask application is an instance of the Flask class, which collects all configuration, extensions, and views.
Template Inheritance — Flask Documentation (3.1.x)
Template Inheritance The most powerful part of Jinja is template inheritance. Template inheritance allows you to build a base “skeleton” template that contains all the common elements of your site and defines blocks that child templates can override. Sounds complicated but is very basic. It’s easiest to understand it by starting with an example. Base Template ¶ This template, …
Testing Flask Applications — Flask Documentation (3.1.x)
Testing Flask Applications ¶ Flask provides utilities for testing an application. This documentation goes over techniques for working with different parts of the application in tests. We will use the pytest framework to set up and run our tests.
Signals — Flask Documentation (3.1.x)
For all core Flask signals, the sender is the application that issued the signal. When you subscribe to a signal, be sure to also provide a sender unless you really want to listen for signals from all applications.