OpenShift + Django + MySQL

August 17th, 2011

I’ve spent the past 3 years developing two django projects.
Nushus: https://fedorahosted.org/nushus
Loki: https://fedorahosted.org/loki

When Red Hat released openshift I was interested to deploy django on it. I use MySQL with my django apps, mainly because that’s what I know well. The tutorial I was working through used sqlite so I’ve put this together to show how I got MySQL working with django on openshift.

Run this quick start to get your account and domain setup
https://openshift.redhat.com/app/express#quickstart
Then login to the website and open this turoial:
https://www.redhat.com/openshift/kb/kb-e1010-show-me-your-django-getting-django-up-and-running-in-5-minutes
Run the ‘Deploying a Django Application’ section of this tutorial to get a basic django app setup and running. Then you’ll have Django setup but with no admin:

After you get here, continue the tutorial related to the usual code edits needed in your django project to enable the admin. Don’t setup the sqlite database as the tutorial suggests, we’ll get connected to MySQL next.
Next lets setup the database:

testapp git:(master)➤ rhc-ctl-app -e add-mysql-5.1 -a testapp
Password:
Contacting https://openshift.redhat.com
Contacting https://openshift.redhat.com

RESULT:

Mysql 5.1 database added.  Please make note of these credentials:

   Root User: SuperSecretUser
   Root Password: SuperSecretPassword

Connection URL: mysql://127.XXX.XXX.XXXX:3306/

This will create the MySQL instance but not the database.
This forum post suggests the current method to get the database setup: https://www.redhat.com/openshift/forums/express/mysql-db-name
We need to also run syncdb, which the django tuorial shows us how to do. It also shows us how to deploy the admin media. I don’t like how the django tutorial makes us commit static code that’s already deployed. Let’s copy it remotely from the egg that’s already deployed into the remote static dir without commiting it. All this is done via the openshift build hook. I’ve rewritten it a bit in process of testing things so it will look a bit different than the tutorials:

testapp git:(master)➤ cat .openshift/action_hooks/build
#!/bin/bash
# This is a simple build script, place your post-deploy but pre-start commands
# in this script.  This script gets executed directly, so it could be python,
# php, ruby, etc.

# create the database if it doesn't exist
# https://www.redhat.com/openshift/forums/express/mysql-db-name
if ! /usr/bin/mysql -u "$OPENSHIFT_DB_USERNAME" --password="$OPENSHIFT_DB_PASSWORD" -h "$OPENSHIFT_DB_HOST" -e "show tables;" $OPENSHIFT_APP_NAME > /dev/null
then
    /usr/bin/mysqladmin -u "$OPENSHIFT_DB_USERNAME" --password="$OPENSHIFT_DB_PASSWORD" -h "$OPENSHIFT_DB_HOST" create "$OPENSHIFT_APP_NAME"
    echo "Created MySQL database $OPENSHIFT_APP_NAME"
fi

# copy the admin media into place
if [ ! -d "$DIRECTORY" ]; then
    if mkdir $OPENSHIFT_REPO_DIR/wsgi/static/admin
    then
        echo "Created directory $OPENSHIFT_REPO_DIR/wsgi/static/admin"
        echo "Copying admin media into $OPENSHIFT_REPO_DIR/wsgi/static/admin"
        cp -R $OPENSHIFT_APP_DIR/virtenv/lib/python2.6/site-packages/Django-1.3-py2.6.egg/django/contrib/admin/media/** $OPENSHIFT_REPO_DIR/wsgi/static/admin
    fi
fi

# cd into the project to run django manage.py commands
cd $OPENSHIFT_REPO_DIR/wsgi/testapp

# run syncdb
# https://www.redhat.com/openshift/kb/kb-e1010-show-me-your-django-getting-django-up-and-running-in-5-minutes
echo "Executing './manage.py syncdb --noinput'"
./manage.py syncdb --noinput

This gets us to the login page for the admin:

Now all that’s missing is a user. I toyed with a couple options to get a basic user in. The command line manage.py won’t let you pass a password and I had trouble getting fixtures to load. Though, both of those required sql to verify if the user existed. Settled on a simple management command to make sure we have a user. We have to put it in an app, but we’re going to need an app eventually anyways to make django so more than start. So here’s what I did.
In the project directory run the django startapp command:

testapp/wsgi/testapp git:(master+)➤ ../manage.py startapp myapp

Then add it to the INSTALLED_APPS in your settings file

+     'testapp.myapp',

You have to put the projects name in there, otherwise things won’t work later. I got 500’s trying just to put just ‘myapp’ in the installed apps. This app won’t really do anything for now. It’s just a container for our management command. You can make it into something else later. Next create the directory structure for the command in the myapp directory.

testapp/wsgi/testapp git:(master+)➤ mkdir -p myapp/management/commands
testapp/wsgi/testapp git:(master+)➤ touch myapp/management/__init__.py myapp/management/commands/__init__.py
testapp/wsgi/testapp git:(master+)➤ vim myapp/management/commands/ensuresuperuser.py
testapp/wsgi/testapp git:(master+)➤ tree myapp
myapp
|-- __init__.py
|-- management
|   |-- commands
|   |   |-- ensuresuperuser.py
|   |   `-- __init__.py
|   `-- __init__.py
|-- models.py
|-- tests.py
`-- views.py

2 directories, 7 files

You can see I called my command ensuresuperuser. The command will check if the user exists and create it with a password equal to the user’s username if the user doesn’t exist. Here’s it’s code:

testapp/wsgi/testapp git:(master+)➤ cat myapp/management/commands/ensuresuperuser.py
from django.core.management.base import BaseCommand, CommandError
from django.contrib.auth.models import User

class Command(BaseCommand):
    args = 'username'
    help = 'make sure a user exists with a password'

    def handle(self, *args, **options):
        try:
            user = User.objects.get(username=args[0])
        except:
            User.objects.create_superuser(args[0], email=args[0]+'@example.com', password=args[0])
            self.stdout.write('user %s created with password %s\n' % (args[0], args[0]))

Last thing to do is to add this command to your build hook so it executes when you push your code, so update your build hook. Here’s the whole contents of mine:

testapp git:(master+)➤ cat .openshift/action_hooks/build
#!/bin/bash
# This is a simple build script, place your post-deploy but pre-start commands
# in this script.  This script gets executed directly, so it could be python,
# php, ruby, etc.

# create the database if it doesn't exist
# https://www.redhat.com/openshift/forums/express/mysql-db-name
if ! /usr/bin/mysql -u "$OPENSHIFT_DB_USERNAME" --password="$OPENSHIFT_DB_PASSWORD" -h "$OPENSHIFT_DB_HOST" -e "show tables;" $OPENSHIFT_APP_NAME > /dev/null
then
    /usr/bin/mysqladmin -u "$OPENSHIFT_DB_USERNAME" --password="$OPENSHIFT_DB_PASSWORD" -h "$OPENSHIFT_DB_HOST" create "$OPENSHIFT_APP_NAME"
    echo "Created MySQL database $OPENSHIFT_APP_NAME"
fi

# copy the admin media into place
if [ ! -d "$DIRECTORY" ]; then
    if mkdir $OPENSHIFT_REPO_DIR/wsgi/static/admin
    then
        echo "Created directory $OPENSHIFT_REPO_DIR/wsgi/static/admin"
        echo "Copying admin media into $OPENSHIFT_REPO_DIR/wsgi/static/admin"
        cp -R $OPENSHIFT_APP_DIR/virtenv/lib/python2.6/site-packages/Django-1.3-py2.6.egg/django/contrib/admin/media/** $OPENSHIFT_REPO_DIR/wsgi/static/admin
    fi
fi

# cd into the project to run django manage.py commands
cd $OPENSHIFT_REPO_DIR/wsgi/testapp

# run syncdb
# https://www.redhat.com/openshift/kb/kb-e1010-show-me-your-django-getting-django-up-and-running-in-5-minutes
echo "Executing './manage.py syncdb --noinput'"
./manage.py syncdb --noinput

# add an admin user
./manage.py ensuresuperuser admin

This time when you commit and push everything you will see it tell you “user admin created with password admin”. Obviously this is really insecure so go ahead and change that password right away. Wouldn’t want your throw away testapp become something it wasn’t intended for.

There you have it, OpenShift + Django + MySQL.
It’s worth noting, If you get a 500 error you need to use the rhc-snapshot command like so:

testapp git:(master+)➤ rhc-snapshot -a testapp
Password:
Contacting https://openshift.redhat.com
Pulling down a snapshot to testapp.tar.gz

This pulls down a tar ball of your running environment and has a logs directory in there that you can look at the apache logs. I’ll second Ian’s suggestion for a rhc-logwatch command. That would be pretty handy.

Next steps for me:
1. How to delete an OpenShift application (i.e. throw away testapp, I’m done with it)
2. Install Nushus in OpenShift!

*** Update ***
I came across another blog post a day later that reference rhc-tail-files. i.e. the watchlog thing I mentioned above is already a feature:

testapp git:(master+)➤ rhc-tail-files -a testapp
Password: 
Contacting https://openshift.redhat.com
Attempting to tail files: testapp/logs/*
Use ctl + c to stop

==> testapp/logs/access_log-20110817-000000-EST <==
... snip log files output ...

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