Category: Python Answers

Sometimes, we want to add a prefix to all Python Flask routes

In this article, we’ll look at how to add a prefix to all Python Flask routes.

How to add a prefix to all Python Flask routes?

To add a prefix to all Python Flask routes, we can create a blueprint.

For instance, we write

bp = Blueprint('burritos', __name__,
                        template_folder='templates')

@bp.route("/")
def index_page():
  return "eat burritos"

@bp.route("/about")
def about_page():
  return "eat burritos"

to create the bp blueprint with the Blueprint class.

We call it with the burritos' string to set that as the blueprint name.

Then we create routes in the blueprint with the bp.route decorator.

Next, we register our blueprint with app.register_blueprint

app = Flask(__name__)
app.register_blueprint(bp, url_prefix='/abc/123')

We set the URL prefix by setting the url_prefix argument when registering.

Conclusion

To add a prefix to all Python Flask routes, we can create a blueprint.

Sometimes, we want to debug a Python Flask app.

In this article, we’ll look at how to debug a Python Flask app.

How to debug a Python Flask app?

To debug a Python Flask app, we set the FLASK_APP and FLASK_ENV environment variables before running the app.

To do this on Linux and Mac, we run

export FLASK_APP=myapp
export FLASK_ENV=development
flask run

to set the environment variables with export.

And then we run flask run to run the app.

On Windows, we replace export with set in the command prompt.

And in Windows PowerShell, we run

$env:FLASK_ENV = "development"

to set the environment variables with $env:.

Conclusion

To debug a Python Flask app, we set the FLASK_APP and FLASK_ENV environment variables before running the app.

Sometimes, we want to fix Python Flask view returning error "View function did not return a response"

In this article, we’ll look at how to fix Python Flask view returning error "View function did not return a response".

How to fix Python Flask view returning error "View function did not return a response"?

To fix Python Flask view returning error "View function did not return a response", we should return a response in our view.

For instance, we write

@app.route('/hello', methods=['GET', 'POST'])
def hello():
    return hello_world()

to return the value returned by hello_world as the response in the hello view function.

Conclusion

To fix Python Flask view returning error "View function did not return a response", we should return a response in our vie

Sometimes, we want to fix Python Flask raising TemplateNotFound error even though template file exists.

In this article, we’ll look at how to fix Python Flask raising TemplateNotFound error even though template file exists.

How to fix Python Flask raising TemplateNotFound error even though template file exists?

To fix Python Flask raising TemplateNotFound error even though template file exists, we can set the template_folder to the folder with the templates in our project.

For instance, we write

app = Flask(__name__, template_folder='template') 

to set the template_folder argument to the path string relative to our project folder.

Conclusion

To fix Python Flask raising TemplateNotFound error even though template file exists, we can set the template_folder to the folder with the templates in our project.

Sometimes, we want to pass HTML to template using Python Flask and Jinja2.

In this article, we’ll look at how to pass HTML to template using Python Flask and Jinja2.

How to pass HTML to template using Python Flask and Jinja2?

To pass HTML to template using Python Flask and Jinja2, we can use the safe filter.

For instance, we write

{{ something|safe }}

to render something string as HTML by using the safe filter.

Conclusion

To pass HTML to template using Python Flask and Jinja2, we can use the safe filter.