mod_wsgi - user option in WSGIDaemonProcess doesn't work

Question

I'm trying to configure my wsgi app to run under my user id. The OS is Ubuntu 13.10. This is virtual host config:

<VirtualHost *:80>

  ServerName  lz5.local
  DocumentRoot /home/kompas/git/lz5/front-app

  WSGIDaemonProcess lz user=#1000 group=#1000
  WSGIApplicationGroup lz

  <Directory /home/kompas/git/lz5>
          AllowOverride None
          Require all granted
  </Directory>

  LogFormat "%V %l %u %t \"%r\" %>s %b" common_vhost
  CustomLog "/var/log/apache2/logzilla_access.log" common_vhost
  ErrorLog  "/var/log/apache2/logzilla_error.log"

  WSGIScriptAlias /api /home/kompas/git/lz5/app.wsgi

</VirtualHost>

And this is my app.wsgi:

(...imports...)

sys.stderr.write("My uid={}, gid={}, euid={}, egid={}".format(
    os.getuid(), os.getgid(), os.geteuid(), os.getegid()))
sys.stderr.flush()

application = make_app()
application.debug = True

It seems to be working fine:

[Wed Mar 12 09:55:45.059101 2014] [:info] [pid 25068:tid 139724309714816] mod_wsgi (pid=25068): Starting process 'lz' with uid=1000, gid=1000 and threads=15.

...but in the app.wsgi uid is not changed:

[Wed Mar 12 09:55:49.457056 2014] [:error] [pid 25070:tid 139724094150400] My uid=33, gid=33, euid=33, egid=33

I also noticed, that there's some apache process group with uid set properly to "kompas" (uid 1000), but this is not the one which runs my app!

apache2(23368)─┬─apache2(25479,www-data)─┬─{apache2}(25526)
               ...
               ├─apache2(25480,www-data)─┬─{apache2}(25499)
               │                         ├─{apache2}(25500)
               ...
               └─apache2(25478,kompas)─┬─{apache2}(25481)
                                       ├─{apache2}(25482)

But the pid I get from my app.wsgi is 25480, not 25478 as I'd expect.

Any ideas?

Answer 1

You are missing a WSGIProcessGroup directive to tell mod_wsgi what daemon process group to run your application in.

Go read:

• http://blog.dscpl.com.au/2012/10/why-are-you-using-embedded-mode-of.html
• http://code.google.com/p/modwsgi/wiki/CheckingYourInstallation#Embedded_Or_Daemon_Mode

What you should be using is:

WSGIProcessGroup lz
WSGIApplicationGroup %{GLOBAL}