django db with ssh tunnel

Is there a python native way to connect django to a database through an ssh tunnel? I have seen people using ssh port forwarding in the host machine but I would prefer a solution that can be easily containerized.

Answer

It is pretty seamless.

Requirements: The sshtunnel package https://github.com/pahaz/sshtunnel

1. In the django settings.py create an ssh tunnel before the django DB settings block:

from sshtunnel import SSHTunnelForwarder

# Connect to a server using the ssh keys. See the sshtunnel documentation for using password authentication
ssh_tunnel = SSHTunnelForwarder(
    SERVER_IP,
    ssh_private_key=PATH_TO_SSH_PRIVATE_KEY,
    ssh_private_key_password=SSH_PRIVATE_KEY_PASSWORD,
    ssh_username=SSH_USERNAME,
    remote_bind_address=('localhost', LOCAL_DB_PORT_ON_THE_SERVER),
)
ssh_tunnel.start()

2. Then add the DB info block in the settings.py. Here I am adding a default local DB and the remote DB that we connect to using the ssh tunnel

DATABASES = {
    'default': {
        'ENGINE': 'django.contrib.gis.db.backends.postgis',
        'HOST': NORMAL_DB_HOST,
        'PORT': NORMAL_DB_PORT,
        'NAME': NORMAL_DB_NAME,
        'USER': NORMAL_DB_USER,
        'PASSWORD': NORMAL_DB_PASSWORD,
    },
    'shhtunnel_db': {
        'ENGINE': 'django.contrib.gis.db.backends.postgis',
        'HOST': 'localhost',
        'PORT': ssh_tunnel.local_bind_port,
        'NAME': REMOTE_DB_DB_NAME,
        'USER': REMOTE_DB_USERNAME,
        'PASSWORD': REMOTE_DB_PASSWORD,
    },
}

That is it. Now one can make migratations to the remote db using commands like $ python manage.py migrate --database=shhtunnel_db or make calls to the db from within the python code using lines like Models.objects.all().using('shhtunnel_db')

Extra: In my case the remote db was created by someone else and I only wanted to read it. In order to avoid writing the models and deactivating the model manager I used the following django command to get the models from the database [src]:

python manage.py inspectdb