how to write test cases for authenticated urls in flask

Question

I am using flask with mongoengine and Login Manager for session maintaining. I want to write test cases for authenticated views. can any one help/suggestions regarding this.

Answer 1

First off, I recommend using pytest, and the flask-pytest library which contains some great convenience features to make all of this easier.

flask-pytest comes out of the box with a client fixture, which, per the docs, refers to Flask.test_client

What you want to do is mimic a valid session (e.g. however you app is validating that a user is "logged in").

Here is how to do this without any supporting libraries:

import app
from flask import url_for

def test_authenticated_route():
    app.testing = True
    client = app.test_client()

    with client.session_transaction() as sess:
        # here you can assign whatever you need to
        # emulate a "logged in" user...
        sess["user"] = {"email": "test_user@example.com"}

    # now, you can access "authenticated" endpoints
    response = client.get(url_for(".protected_route"))
    assert response.status_code == 200

This is also discussed in the Flask docs.