Operational Notes and Troubleshooting

Keep your development environment healthy and your API running smoothly. This section lists common issues and checks to diagnose and resolve them quickly.

🔧 Missing Dependencies

Ensure all required packages are installed in the correct environment.

Package Install Command
Flask pip install Flask
Flask-RESTful pip install Flask-RESTful
Flask-JWT pip install Flask-JWT
Flask-SQLAlchemy pip install Flask-SQLALCHEMY

Steps to verify:

  • Activate your virtual environment before installing .
  • Run pip list to confirm packages are present.
  • If you still see an ImportError, reinstall dependencies with: 
    pip install -r requirements.txt
    or individually as needed.
{
  "title": "Activate Venv",
  "content": "Always activate your virtual environment before installing dependencies."
}

🐍 Wrong Python Version

The project targets Python 3.8. Running it on a substantially different version may cause compatibility issues, especially with older Flask-JWT releases .

  • Verify your interpreter: 
    python --version
  • If needed, create a new virtual environment with Python 3.8: 
    virtualenv venv --python=python3.8

💾 Database Not Updating

If your POST/PUT/DELETE requests appear successful but the database does not change, check the following:

  • Debug Mode
    Ensure the app runs with debug enabled for full error output : 
    if __name__ == '__main__':
    db.init_app(app)
    app.run(port=5000, debug=True)
  • Correct Base URL
    Send requests to http://localhost:5000/... (or your configured host and port).
  • Commit Calls
    Confirm save_to_db and delete_from_db invoke db.session.commit() : 
    def save_to_db(self):
    db.session.add(self)
    db.session.commit()

def delete_from_db(self):
    db.session.delete(self)
    db.session.commit()
  • Server Logs
    Inspect console output for swallowed exceptions or SQL errors.

🔐 JWT Token Not Set in Postman

Protected endpoints require a valid JWT. If you receive 401 Unauthorized, follow these checks:

  • Run /auth First
    Authenticate and obtain a token via the Postman /auth request.
  • Test Script Enabled
    Verify the test script saves access_token to jwt_token : 
    pm.test("JWT Token Not Empty", function () {
    var jsonData = pm.response.json();
    pm.globals.set("jwt_token", jsonData.access_token);
});
  • Correct Header
    Use the variable in subsequent requests: 
    Authorization: JWT {{jwt_token}}
  • Order of Requests
    Ensure /auth runs and passes before any protected call.

Stay proactive: monitor logs, keep dependencies current, and verify environment settings. Happy coding!

Updated