Cannot get gunicorn to use Python 3

Question

I have Ubuntu+NGINX+Gunicorn with a virtual environment that works with Python 3 setup but my Flask app still runs as 2.7.6. I have methodically followed the instructions but I cannot find a resolution.

Gunicorn config file

[program:app-server]
command = gunicorn app:app -b localhost:8000
directory = /home/www/app-server
user = appuser

Project directory structure

app-server    
----app.py
----venv (virtual environment)

Answer 1

Gunicorn is itself a Python application; the Gunicorn PPA only publishes Python 2 versions.

You'd install Gunicorn into Python 3 instead (using pip, preferably into your virtualenv) and run that version:

/home/www/app-server/venv/bin/gunicorn

Answer 2

Although the question is more than a year old, but i figured i should add my answer in case any one come searching

open this file "/usr/bin/gunicorn" with a text editor. In my case I used vim with sudo in other to be able to edit the file

then change the python version to python3 usr/bin/python2.7 will be usr/bin/python3

then change the version number in the file to the version number of the gunicorn installed in virtual env. directory if both are not the same. In my case the version number in the file was 17.0 but what i have is 19.6.0

Note that there are two places to change the version number in the file.

    #! /usr/bin/python3
    # EASY-INSTALL-ENTRY SCRIPT'gunicorn==17.5','console_scripts','gunicorn'
    __requires__ = 'gunicorn==19.6.0'
    import sys
    from pkg_resources import load_entry_point

    if __name__ == '__main__':
        sys.exit(
                  load_entry_point('gunicorn==19.6.0', console_scripts, 
                   'gunicorn')
                )