Flask app deployment, start command?

[RiddSarav]

Hello,

I am very new to render and I am trying to deploy my first flask app here but I am not able to understand what is the “start” command, I followed numerous tutorials that all used guincorn app:app but for some reason it does not work for me?

Any tips on what to do?

Thanks

[jeremy-render]

Hey,

gunicorn is a command that will allow you to start an http server that serves your Flask app.

Please check the quick-start documentation of gunicorn first: https://docs.gunicorn.org/en/latest/run.html so you can get an idea of what the command does.

You should tweak the command depending on how you’ve called/created your app.

If you require any help, please share some error messages, code snippets, etc…

Jérémy, Render Support

[RiddSarav]

Hello,

Thanks for the response, is the first “app” the file name and the second “app” for “app = Flask(name)” I saw a few resources which said, gunicorn app:app is similar to from app import app but I have “app = Flask(name)” inside the file called app.py?

I am very confused, any thing I can do to fix it?

[jeremy-render]

Hey Ridd,

If we look at gunicorn’s documentation, we can see:

Basic usage:

$ gunicorn [OPTIONS] [WSGI_APP]

Where WSGI_APP is of the pattern $(MODULE_NAME):$(VARIABLE_NAME). The module name can be a full dotted path. The variable name refers to a WSGI callable that should be found in the specified module.

So, your module name (file name) + a variable within the module that can be called by gunicorn

You can also have a look at this Flask specific doc: https://flask.palletsprojects.com/en/2.2.x/deploying/gunicorn/

If you’re still having any issues, please let me know and specify which service you’re having an issue with and what error messages are you seeing.

Jérémy, Render Support