Flask app doesn't work

[andrewmelnyk]

ImportError: cannot import name 'escape' from 'jinja2'

Unfortunately this tutorial no longer works which is weird I thought that the requirements.txt would prevent this from happening. This happens when running docker-compose up in the flask app at this time in the video https://www.youtube.com/watch?v=0iB5IPoTDts&t=16s

[jonaas-dev]

Requirements.txt file should look:

Flask>=2.2.2
Flask-SQLAlchemy==2.4.4
SQLAlchemy==1.3.20
Flask-Migrate==2.5.3
Flask-Script==2.0.6
Flask-Cors==3.0.9
requests==2.25.0
mysqlclient==2.0.1
pika==1.1.0

After modifying the requirements.txt file, rebuild your Docker image to ensure the changes take effect. You can do this by running docker-compose build.

Finally, run your Docker containers again with docker-compose up.

[samprit-ghosh]

If you are encountering an issue where you cannot import the escape function from the jinja2 module in your Flask application, it may be due to changes in the version of Jinja2 that you are using. The escape function is commonly used to safely escape HTML entities in templates to prevent cross-site scripting (XSS) attacks.

Here are a few steps you can take to address this issue:

1. Check Jinja2 Version:
   Make sure that you are using a version of Jinja2 that supports the escape function. The escape function has been a part of Jinja2 for a long time, but it's good to ensure you have a relatively recent version. You can check your Jinja2 version by running:

   pip show jinja2

   Update Jinja2 to the latest version if needed:

   pip install --upgrade jinja2

2. Correct Import Statement:
   In your Flask application, when you import the escape function, make sure you use the correct import statement. It should look like this:

   from jinja2 import escape

   Ensure that this import statement is used in the relevant part of your code.

3. Check for Circular Imports:
   Circular imports can sometimes cause import issues. Make sure there are no circular dependencies in your project that might be affecting the import.

4. Check Dependencies:
   Ensure that your project's dependencies are consistent and do not have conflicts. You can check and update your dependencies using:

   pip freeze > requirements.txt

   And then, if needed:

   pip install -r requirements.txt

5. Check Flask Version:
   Make sure you are using a compatible version of Flask. Flask and Jinja2 are often tightly coupled, and using versions that are not compatible with each other can lead to issues.

If you've tried these steps and are still experiencing the problem, consider providing more details about your Flask application structure, the version of Flask and Jinja2 you are using, and any relevant code snippets. This additional information will help in diagnosing the issue more accurately.