Re: Looking for documention on deploying roundup with mod_wsgi

Hi John!

* John P. Rouillard <[email protected]> [20191008 02:55]:
> In message <[email protected]>,
> Thomas Arendsen Hein writes:
> >Not with so much detail, but here are some snippets that might be
> >useful:
> 
> I am using your wsgi as the example wsgi script for the WSGI Handler
> section since it seems the script that was there was broken. I like
> the ability to shut off the script for maintenance.

I have a similar mechanism for the mail gateway, but did not want to
complicate this topic. Feel free to ask me after the wsgi stuff is
finihed :)

> Listen at port 80
> 
> >    <VirtualHost *:80>
> >            CustomLog /var/log/apache2/access.log vhost_combined
> >
> >            Alias /doc/ /home/roundup/install/share/doc/roundup/html/

This directive does not make Apache listen on port 80, but it will
make it react if a request it receives on port 80 matches the host
name (which is "*" here, so matches anything)

On Debian systems there is a /etc/apache2/ports.conf with the
corresponding "Listen" configuration. On CentOS this is in
/etc/httpd/conf/httpd.conf and/or /etc/httpd/conf.d/ssl.conf, other
systems have again different locations, so I think this should not
be discussed in the Roundup docs.

> I assume this allows apache to directly serve up static files like css
> etc rather than going through the wsgi roundup instance?
> 
> >            Alias /foo/@@file/ /srv/roundup/foo/html/

Yes, correct.

> Remap /foo to /foo/ I assume?
> 
> >            RedirectMatch permanent ^/(foo)$ /$1/

Yes, correct.

> >            WSGIDaemonProcess roundup-foo display-name=roundup-foo user=roundup-foo group=roundup-foo threads=25
> 
> This makes /foo run the wsgi script and pass remaining url path
> to the wsgi as path info and query args?
> 
> >            WSGIScriptAlias /foo /srv/roundup/foo/roundup.wsgi
> >            <Location /foo>
> >                    WSGIProcessGroup roundup-foo
> >            </Location>
> >    </VirtualHost>

Yes, correct. The WSGIScriptAlias does the mapping to a script,
the other lines are important to e.g. change the user from www-data
to roundup-foo.

> >(https can be configured here, too, but we do this elsewhere)
> 
> Do you have an example stanza to enable https?

<VirtualHost *:443>
        SSLEngine on
        SSLCertificateFile      /path/to/cert.pem
        SSLCertificateKeyFile   /path/to/key.pem
        SSLCertificateChainFile /path/to/cacert.pem
        ...other things like in the http section...
</VirtualHost>

And on Debian you can use "a2enmod ssl" to enable ssl support.

Optionally put this in your http section to enforce https:

        Redirect / https://roundup.example.com/

But often distributions already contain en example configuration for
https, which already includes suitable paths and other things.

> >Use "a2ensite roundup" and "a2dissite default" to enable only the
> >roundup configuration.
> 
> What happens if you don't turn off default?

Then the config from the default site is still active. Maybe it
serves something below /, maybe it conflicts and Apache complains,
don't try this at home :)

> >/srv/roundup/foo/ contains the Roundup instance and the file
> >roundup.wsgi:
> >
> >    import sys, os
> >    sys.stdout = sys.stderr
> >
> >    enabled = True
> >
> >    if enabled:
> >        sys.path.insert(0, '/home/roundup/install/lib/python')
> >        # obtain the WSGI request dispatcher
> >        from roundup.cgi.wsgi_handler import RequestDispatcher
> >        tracker_home = os.path.join(os.getcwd(), 'instance')
> 
> This line I don't get. Does apache or mod_wsgi automatically cd to
> /home/roundup-foo and how does it know to start there?

The user account is roundup-foo (due to the WSGIDaemonProcess
setting above), so it automatically changes to the home directory of
this user.

You could alternatively use:

    tracker_home = os.path.expanduser('~/instance')

Or if you want to avoid using the symlink in $HOME and maybe avoid
having the username used as a path component, you can set it
directly:

    tracker_home = '/srv/roundup/roundup-foo'

(but I wanted an identical wsgi script for multiple trackers)

> >        application = RequestDispatcher(tracker_home)
> 
> and magic happens....

:)

Regards,

Thomas

-- 
Thomas Arendsen Hein <[email protected]>
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