Green Unicorn, Django & nginx stuff you should read

Two months ago I wrote a guide on running Django apps using Gunicorn and nginx, I’ve been reading a lot of stuff lately on the Internet about the topic. Here there are several pages you should read:

Run Django apps using Gunicorn and nginx

Some days ago, I read this tweet by @jessenoller (via @DZPM):

The future is DUNG: Django, Unix, Nginx, Gunicorn. I plan on asking HR to look for DUNG on all resumes.

What the heck is Gunicorn, I wondered… In short, Gunicorn is a Python WSGI HTTP Server easy to set up that gets on well with Django. Running Django apps using my beloved nginx gets faster and easier using Ubuntu Lucid Lynx. Look below…

  • Install packages (I assume you’ve already set up nginx)
# apt-add-repository ppa:bchesneau/gunicorn
# aptitude update
# aptitude install gunicorn supervisor python-setuptools
  • Edit settings.py in your Django app and add gunicorn to your INSTALLED_APPS
INSTALLED_APPS = (
  'django.contrib.auth',
  ...
  'gunicorn',
  ...
)
  • Setup the supervisor of Django process in /etc/supervisor/conf.d/djangoapp.conf
[program:djangoapp]
command=/usr/bin/python /path/to/your/app/manage.py run_gunicorn
directory=/path/to/your/app
user=www-data
autostart=true
autorestart=true
redirect_stderr=True
  • Restart supervisor
  • Setup nginx
upstream app_server_djangoapp {
    server localhost:8000 fail_timeout=0;
}

server {
	listen X.X.X.X:80;
	server_name  .example.com;

	access_log  /var/log/nginx/example.com.access.log;
	error_log  /var/log/nginx/example.com.error.log info;

    keepalive_timeout 5;

    # path for static files
    root /path/to/your/app/media;

    location / {
        proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
        proxy_set_header Host $http_host;
        proxy_redirect off;

        if (!-f $request_filename) {
            proxy_pass http://app_server_djangoapp;
            break;
        }
    }
}
  • Have fun

It was crystal clear LAMP’s time was over, could DUNG be the next fashionable acronym in free software web apps world?

Multiple Solr Instances: The Clean (Ubuntu) Way

If you need to run multiple instances (multiCore) of Solr in an Ubuntu Lucid Lynx, and you don’t want to mess your system (you want to do it the aptitude way), follow this recipe:

  • Install Solr
# aptitude install solr-jetty openjdk-6-jdk
  • Edit /etc/default/jetty and enable autostart
NO_START=0
  • Create /usr/share/solr/solr.xml and specify your instances
<solr persistent="true" sharedLib="lib">
  <cores adminPath="/admin/cores">
    <core name="core0" instanceDir="core0" />
    <core name="core1" instanceDir="core1" />
  </cores>
</solr>
  • Create configuration directories for both instances
# cp -Rp /etc/solr/conf /etc/solr/conf-core0
# cp -Rp /etc/solr/conf /etc/solr/conf-core1
# mkdir /usr/share/solr/core0
# mkdir /usr/share/solr/core1
# ln -s /etc/solr/conf-core0 /usr/share/solr/core0/conf
# ln -s /etc/solr/conf-core1 /usr/share/solr/core1/conf
  • Get rid of old stuff
# rm -rf /etc/solr/conf
# rm /usr/share/solr/conf
# rm -rf /var/lib/solr/data
  • Change path of dataDir in /etc/solr/conf-core{0,1}/solrconfig.xml for each instance
<dataDir>/var/lib/solr/core0/data</dataDir>
  • Configure each instance by editing /etc/solr/conf-core{0,1}/solrconfig.xml
  • Start Solr
# /etc/init.d/jetty start
  • Have fun in http://localhost:8080/solr/core0/admin/ and http://localhost:8080/solr/core1/admin/.