Join us and get access to thousands of tutorials and a community of expert Pythonistas.
This lesson is for members only. Join us and get access to thousands of tutorials and a community of expert Pythonistas.
Building the Flask App
00:00
Now on to the Flask app itself. Create a new file app.py.
00:11
The responses from Google will use JSON, and the json package in the Python standard library translates between JSON objects and Python dictionaries.
00:20
The os module is used to manage environment variables. Since the client secret is a sensitive value you should not store it with the app. This app will use an environment variable instead. And sqlite3 is again needed to communicate with the database.
00:36
A number of imports are needed from flask and flask_login, but we’ll explain them in the code.
00:44
The WebApplicationClient is the class that implements the OAuth 2 flow. requests will handle HTTP traffic independent of Flask. Finally, import the method to create the database and the User class.
01:01
Retrieve the client ID and secret from environment variables and store them in constants. And one more constant for the .well-known/ endpoint to retrieve the OIDC provider configuration. At this point, you should also create a shell script to store the client ID and secret in environment variables. Create setup_env.sh…
01:31
and then execute it. Back to app.py. Create a Flask app. The parameter to the Flask() initializer is the name of the application module. For a simple app, the __name__ dunder value will be fine.
01:46
Also, Flask-Login requires a secret key for encryption. Either use one stored in an environment variable or generate a new one. An instance of login_manager will add the session tracking features from Flask-Login.
02:03
Attempt to create the database. Catch a sqlite3.OperationalError in case the database already exists, in which case you should do nothing. Initialize the client with the client ID. Flask-Login depends upon a function designated as the user_loader to get a User instance given a certain user_id.
02:26 In the next lesson, you’ll define the endpoints for the app and code up the OAuth dance.
ynotmarygrace on Feb. 6, 2021
Hi… import click is not working… There is an error… Can you please help me?
Become a Member to join the conversation.
ynotmarygrace on Feb. 5, 2021
Hi everyone. Video is not working for this: realpython.com/lessons/building-flask-app/