Installation

Assuming you have django installed, the first step is to install django-tenant-schemas.

pip install django-tenant-schemas

Basic Settings

You’ll have to make the following modifications to your settings.py file.

Your DATABASE_ENGINE setting needs to be changed to

DATABASES = {
    'default': {
        'ENGINE': 'tenant_schemas.postgresql_backend',
        # ..
    }
}

Add tenant_schemas.routers.TenantSyncRouter to your DATABASE_ROUTERS setting, so that the correct apps can be synced, depending on what’s being synced (shared or tenant).

DATABASE_ROUTERS = (
    'tenant_schemas.routers.TenantSyncRouter',
)

Add the middleware tenant_schemas.middleware.TenantMiddleware to the top of MIDDLEWARE_CLASSES, so that each request can be set to use the correct schema.

MIDDLEWARE_CLASSES = (
    'tenant_schemas.middleware.TenantMiddleware',
    #...
)

Make sure you have django.core.context_processors.request listed under TEMPLATE_CONTEXT_PROCESSORS else the tenant will not be available on request.

TEMPLATE_CONTEXT_PROCESSORS = (
    'django.core.context_processors.request',
    #...
)

The Tenant Model

Now we have to create your tenant model. Your tenant model can contain whichever fields you want, however, you must inherit from TenantMixin. This Mixin only has two fields (domain_url and schema_name) and both are required. Here’s an example, suppose we have an app named customers and we want to create a model called Client.

from django.db import models
from tenant_schemas.models import TenantMixin

class Client(TenantMixin):
    name = models.CharField(max_length=100)
    paid_until =  models.DateField()
    on_trial = models.BooleanField()
    created_on = models.DateField(auto_now_add=True)

    # default true, schema will be automatically created and synced when it is saved
    auto_create_schema = True

Configure Tenant and Shared Applications

To make use of shared and tenant-specific applications, there are two settings called SHARED_APPS and TENANT_APPS. SHARED_APPS is a tuple of strings just like INSTALLED_APPS and should contain all apps that you want to be synced to public. If SHARED_APPS is set, then these are the only apps that will be synced to your public schema! The same applies for TENANT_APPS, it expects a tuple of strings where each string is an app. If set, only those applications will be synced to all your tenants. Here’s a sample setting

SHARED_APPS = (
    'tenant_schemas',  # mandatory
    'customers', # you must list the app where your tenant model resides in

    'django.contrib.contenttypes',

    # everything below here is optional
    'django.contrib.auth',
    'django.contrib.sessions',
    'django.contrib.sites',
    'django.contrib.messages',
    'django.contrib.admin',
)

TENANT_APPS = (
    # The following Django contrib apps must be in TENANT_APPS
    'django.contrib.contenttypes',

    # your tenant-specific apps
    'myapp.hotels',
    'myapp.houses',
)

INSTALLED_APPS = list(set(SHARED_APPS + TENANT_APPS))

You also have to set where your tenant model is.

TENANT_MODEL = "customers.Client" # app.Model

Now run migrate_schemas --shared (sync_schemas --shared if you’re on Django 1.6 or older), this will create the shared apps on the public schema. Note: your database should be empty if this is the first time you’re running this command.

# Django >= 1.7
python manage.py migrate_schemas --shared

# Django < 1.7
python manage.py sync_schemas --shared

Warning

Never use syncdb as it would sync all your apps to public!

Lastly, you need to create a tenant whose schema is public and it’s address is your domain URL. Please see the section on use.

You can also specify extra schemas that should be visible to all queries using PG_EXTRA_SEARCH_PATHS setting.

PG_EXTRA_SEARCH_PATHS = ['extensions']

PG_EXTRA_SEARCH_PATHS should be a list of schemas you want to make visible globally.

Tip

You can create a dedicated schema to hold postgresql extensions and make it available globally. This helps avoid issues caused by hiding the public schema from queries.

South Migrations

If you’re on Django 1.6 or older, this app supports South so if you haven’t configured it yet and would like to:

For Django 1.1 or below

SOUTH_DATABASE_ADAPTER = 'south.db.postgresql_psycopg2'

For Django 1.2 or above

SOUTH_DATABASE_ADAPTERS = {
    'default': 'south.db.postgresql_psycopg2',
}

You can list south under TENANT_APPS and SHARED_APPS if you want.

We override south‘s syncdb and migrate command, so you’ll need to change your INSTALLED_APPS to

INSTALLED_APPS = SHARED_APPS + TENANT_APPS + ('tenant_schemas',)

This makes sure tenant_schemas is the last on the list and therefore always has precedence when running an overridden command.

Optional Settings

PUBLIC_SCHEMA_NAME
Default:'public'

The schema name that will be treated as public, that is, where the SHARED_APPS will be created.

TENANT_CREATION_FAKES_MIGRATIONS
Default:'True'

Sets if the models will be synced directly to the last version and all migration subsequently faked. Useful in the cases where migrations can not be faked and need to be ran individually. Be aware that setting this to False may significantly slow down the process of creating tenants. Only relevant if South is used.

Tenant View-Routing

PUBLIC_SCHEMA_URLCONF
Default:None

We have a goodie called PUBLIC_SCHEMA_URLCONF. Suppose you have your main website at example.com and a customer at customer.example.com. You probably want your user to be routed to different views when someone requests http://example.com/ and http://customer.example.com/. Because django only uses the string after the host name, this would be impossible, both would call the view at /. This is where PUBLIC_SCHEMA_URLCONF comes in handy. If set, when the public schema is being requested, the value of this variable will be used instead of ROOT_URLCONF. So for example, if you have

PUBLIC_SCHEMA_URLCONF = 'myproject.urls_public'

When requesting the view /login/ from the public tenant (your main website), it will search for this path on PUBLIC_SCHEMA_URLCONF instead of ROOT_URLCONF.

Separate projects for the main website and tenants (optional)

In some cases using the PUBLIC_SCHEMA_URLCONF can be difficult. For example, Django CMS takes some control over the default Django URL routing by using middlewares that do not play well with the tenants. Another example would be when some apps on the main website need different settings than the tenants website. In these cases it is much simpler if you just run the main website example.com as a separate application.

If your projects are ran using a WSGI configuration, this can be done by creating a filed called wsgi_main_website.py in the same folder as wsgi.py.

# wsgi_main_website.py
import os
os.environ.setdefault("DJANGO_SETTINGS_MODULE", "project.settings_public")

from django.core.wsgi import get_wsgi_application
application = get_wsgi_application()

If you put this in the same Django project, you can make a new settings_public.py which points to a different urls_public.py. This has the advantage that you can use the same apps that you use for your tenant websites.

Or you can create a completely separate project for the main website.

Configuring your Apache Server (optional)

Here’s how you can configure your Apache server to route all subdomains to your django project so you don’t have to setup any subdomains manually.

<VirtualHost 127.0.0.1:8080>
    ServerName mywebsite.com
    ServerAlias *.mywebsite.com mywebsite.com
    WSGIScriptAlias / "/path/to/django/scripts/mywebsite.wsgi"
</VirtualHost>

Django’s Deployment with Apache and mod_wsgi might interest you too.

Building Documentation

Documentation is available in docs and can be built into a number of formats using Sphinx. To get started

pip install Sphinx
cd docs
make html

This creates the documentation in HTML format at docs/_build/html.