Flask - WSGI - No module named 'flask'

Question

I've been following Sentdex' Flask tutorial. He's using a Venv to set up his Flask, but didn't set his Python up to work with a Venv. I've tried installing Flask globally - yet it still doesn't work. Trying to browse to the server returns a 500 Internal Server Error

I'm getting the usual no module named flaskerror.

errorFGL.log

[Sun Feb 05 11:22:32.043925 2017] [wsgi:error] [pid 26340:tid 118578538694400] [client 86.52.205.25:49814] mod_wsgi (pid=26340): Target WSGI script '/var/www-fgl/FlaskApp/flaskapp.wsgi' cannot be loaded as Python module.
[Sun Feb 05 11:22:32.044105 2017] [wsgi:error] [pid 26340:tid 118578538694400] [client 86.52.205.25:49814] mod_wsgi (pid=26340): Exception occurred processing WSGI script '/var/www-fgl/FlaskApp/flaskapp.wsgi'.
[Sun Feb 05 11:22:32.044243 2017] [wsgi:error] [pid 26340:tid 118578538694400] [client 86.52.205.25:49814] Traceback (most recent call last):
[Sun Feb 05 11:22:32.045011 2017] [wsgi:error] [pid 26340:tid 118578538694400] [client 86.52.205.25:49814]   File "/var/www-fgl/FlaskApp/flaskapp.wsgi", line 8, in <module>
[Sun Feb 05 11:22:32.045070 2017] [wsgi:error] [pid 26340:tid 118578538694400] [client 86.52.205.25:49814]     from FlaskApp import app as application
[Sun Feb 05 11:22:32.045549 2017] [wsgi:error] [pid 26340:tid 118578538694400] [client 86.52.205.25:49814]   File "/var/www-fgl/FlaskApp/FlaskApp/__init__.py", line 1, in <module>
[Sun Feb 05 11:22:32.045594 2017] [wsgi:error] [pid 26340:tid 118578538694400] [client 86.52.205.25:49814]     from flask import Flask
[Sun Feb 05 11:22:32.045689 2017] [wsgi:error] [pid 26340:tid 118578538694400] [client 86.52.205.25:49814] ImportError: No module named 'flask'

__init__.py

from flask import Flask

app = Flask(__name__)

@app.route('/')
def homepage():
    return "Success"

if __name__ == "__main__":
    app.run()

flaskapp.wsgi

#!/usr/bin/python
import sys
import logging
logging.basicConfig(stream=sys.stderr)

sys.path.insert(0,"/var/www-fgl/FlaskApp/")

from FlaskApp import app as application
application.secret_key = '[REDACTED]'

fgl-database.conf

<VirtualHost *:80>
        ServerName [REDACTED]
        WSGIScriptAlias / /var/www-fgl/FlaskApp/flaskapp.wsgi
        <Directory /var/www-fgl>
            Require all granted
        </Directory>
        Alias /static /var/www-fgl/FlaskApp/FlaskApp/static
        <Directory /var/www-fgl/FlaskApp/FlaskApp/static/>
            Require all granted
        </Directory>
        ErrorLog ${APACHE_LOG_DIR}/errorFGL.log
        LogLevel warn
        CustomLog ${APACHE_LOG_DIR}/accessFGL.log combined




</VirtualHost>

Answer 1

I wasted about 25 minutes finding a solution to this and after following all the other resources I could find, I also did the following:

sudo apt-get install libapache2-mod-wsgi-py3

Make sure to have '-py3' at the end of libapache2-mod-wsgi-py3 or the runtime will default to Python2.7

Source: https://vishnut.me/blog/ec2-flask-apache-setup.html

Answer 2

As is polite behaviour when finding the solution, I googled around a bit more, and somehow managed to find a solution from a YouTube commment by Nathan Nichols here:

https://www.digitalocean.com/community/tutorials/how-to-run-django-with-mod_wsgi-and-apache-with-a-virtualenv-python-environment-on-a-debian-vps

1. Edit /etc/apache2/sites-available/FlaskApp.conf

2. Add the following two lines before the "WSGIScriptAlias" line:

   WSGIDaemonProcess FlaskApp python-path=/var/www/FlaskApp:/var/www/FlaskApp/FlaskApp/venv/lib/python2.7/site-packages
   WSGIProcessGroup FlaskApp
   

3. Restart Apache with "service apache2 restart"

I of course replaced the Python version with python3.5, which is what I'm running.