If all other deployment methods do not work, CGI will work for sure. CGI is supported by all major servers but usually has a sub-optimal performance.
This is also the way you can use a Flask application on Google’s App Engine, where execution happens in a CGI-like environment.
Watch Out
Please make sure in advance that any app.run() calls you might
have in your application file are inside an if __name__ ==
'__main__': block or moved to a separate file. Just make sure it’s
not called because this will always start a local WSGI server which
we do not want if we deploy that application to CGI / app engine.
With CGI, you will also have to make sure that your code does not contain
any print statements, or that sys.stdout is overridden by something
that doesn’t write into the HTTP response.
Creating a [UNKNOWN NODE title_reference] file
First you need to create the CGI application file. Let’s call it
yourapplication.cgi:
#!/usr/bin/python
from wsgiref.handlers import CGIHandler
from yourapplication import app
CGIHandler().run(app)
Server Setup
Usually there are two ways to configure the server. Either just copy the
.cgi into a cgi-bin (and use [UNKNOWN NODE title_reference] or something similar to
rewrite the URL) or let the server point to the file directly.
In Apache for example you can put something like this into the config:
ScriptAlias /app /path/to/the/application.cgi
On shared webhosting, though, you might not have access to your Apache config.
In this case, a file called .htaccess, sitting in the public directory you want
your app to be available, works too but the ScriptAlias directive won’t
work in that case:
RewriteEngine On
RewriteCond %{REQUEST_FILENAME} !-f # Don't interfere with static files
RewriteRule ^(.*)$ /path/to/the/application.cgi/$1 [L]
For more information consult the documentation of your webserver.