django-cumulus

The aim of django-cumulus is to provide a set of tools to utilize Rackspace Cloud Files through Django. It currently includes a custom file storage class, CloudFilesStorage.

Installation

To install the latest release from PyPI using pip:

pip install django-cumulus

To install the development version using pip:

pip install -e git://github.com/richleland/django-cumulus.git#egg=django-cumulus

Add cumulus to INSTALLED_APPS:

INSTALLED_APPS = (
    ...
    'cumulus',
    ...
)

Usage

Add the following to your project’s settings.py file:

CUMULUS = {
    'USERNAME': 'YourUsername',
    'API_KEY': 'YourAPIKey',
    'CONTAINER': 'ContainerName'
}
DEFAULT_FILE_STORAGE = 'cumulus.storage.CloudFilesStorage'

Alternatively, if you don’t want to set the DEFAULT_FILE_STORAGE, you can do the following in your models:

from cumulus.storage import CloudFilesStorage

cloudfiles_storage = CloudFilesStorage()

class Photo(models.Model):
    image = models.ImageField(storage=cloudfiles_storage, upload_to='photos')
    alt_text = models.CharField(max_length=255)

Then access your files as you normally would through templates:

<img src="{{ photo.image.url }}" alt="{{ photo.alt_text }}" />

Or through Django’s default ImageField or FileField api:

>>> photo = Photo.objects.get(pk=1)
>>> photo.image.width
300
>>> photo.image.height
150
>>> photo.image.url
http://c0000000.cdn.cloudfiles.rackspacecloud.com/photos/some-image.jpg

Static media

django-cumulus will work with Django’s built-in collectstatic management command out of the box. You need to supply a few additional settings:

CUMULUS = {
    'STATIC_CONTAINER': 'YourStaticContainer'
}
STATICFILES_STORAGE = 'cumulus.storage.CloudFilesStaticStorage'

Context Processor

django-cumulus includes an optional context_processor for accessing the full CDN_URL of any container files from your templates.

This is useful when you’re using Cloud Files to serve you static media such as css and javascript and don’t have access to the ImageField or FileField‘s url() convenience method.

Add cumulus.context_processors.cdn_url to your list of context processors in your project’s settings.py file:

TEMPLATE_CONTEXT_PROCESSORS = (
    ...
    'cumulus.context_processors.cdn_url',
    ...
)

Now in your templates you can use {{ CDN_URL }} to output the full path to local media:

<link rel="stylesheet" href="{{ CDN_URL }}css/style.css">

Management commands

syncstatic

This management command synchronizes a local static media folder with a remote container. A few extra settings are required to make use of the command.

Add the following required settings:

CUMULUS = {
    'STATIC_CONTAINER': 'MyStaticContainer', # the name of the container to sync with
    'SERVICENET': False, # whether to use rackspace's internal private network
    'FILTER_LIST': [] # a list of files to exclude from sync
}

Invoke the management command:

django-admin.py syncstatic

You can also perform a test run:

django-admin.py syncstatic -t

For a full list of available options:

django-admin.py help syncstatic

container_create

This management command creates a new container in Cloud Files.

Invoke the management command:

django-admin.py container_create <container_name>

For a full list of available options:

django-admin.py help container_create

container_delete

This management command deletes a container in Cloud Files.

Invoke the management command:

django-admin.py container_delete <container_name>

For a full list of available options:

django-admin.py help container_delete

container_info

This management command gathers information about containers in Cloud Files.

Invoke the management command:

django-admin.py container_info [<container_one> <container two> ...]

For a full list of available options:

django-admin.py help container_info

container_list

This management command lists all the items in a Cloud Files container to stdout.

Invoke the management command:

django-admin.py container_list <container_name>

For a full list of available options:

django-admin.py help container_list

Settings

Below are the default settings:

CUMULUS = {
    'API_KEY': None,
    'AUTH_URL': 'us_authurl',
    'CNAMES': None,
    'CONTAINER': None,
    'SERVICENET': False,
    'TIMEOUT': 5,
    'MAX_RETRIES': 5,
    'CONNECTION_ARGS': {},
    'TTL': 86400,
    'USE_SSL': False,
    'USERNAME': None,
    'STATIC_CONTAINER': None,
    'FILTER_LIST': []
}

API_KEY

Required. This is your API access key. You can obtain it from the Rackspace Management Console.

AUTH_URL

Set this to the region your account is in. Valid values are us_authurl (default) and uk_authurl.

CNAMES

A mapping of ugly Rackspace URLs to CNAMEd URLs. Example:

CUMULUS = {
    'CNAMES': {
        'http://c3417812.r12.cf0.rackcdn.com': 'http://media.mysite.com'
    }
}

CONTAINER

Required. The name of the container you want files to be uploaded to.

FILTER_LIST

A list of items to exclude when using the syncstatic management command. Defaults to an empty list.

SERVICENET

Specifies whether to use Rackspace’s private network (True) or not (False). If you host your sites on Rackspace, you should set this to True in production as you will not incur data transfer fees between your server(s) and Cloud Files on the private network.

STATIC_CONTAINER

When using Django’s collectstatic or django-cumulus’s syncstatic command, this is the name of the container you want static files to be uploaded to.

TIMEOUT

The timeout to use when attempting connections to Cloud Files. Defaults to 5 (seconds).

MAX_RETRIES

The number of retry attempts that should be made when a connection or SSL error occurs while reading a file on the container. Defaults to 0. Set this to a higher value if you experience connectivity issues.

CONNECTION_ARGS

Additional keyword arguments to pass to the cloudfiles.Connection instance. Useful for debugging. Default is {}, an empty dict.

TTL

The maximum time (in seconds) until a copy of one of your files distributed into the CDN is re-fetched from your container. Defaults to 86400 (seconds) (24h), the default set by python-cloudfiles.

Note: After changing TTL, caching servers may not recognize the new TTL for this container until the previous TTL expires.

USE_SSL

Whether or not to retrieve the container URL as http (False) or https (True).

USERNAME

Required. This is your API username. You can obtain it from the Rackspace Management Console.

HEADERS

Set headers based on a regular expression in the file name. This can be used to allow Firefox to access webfonts across domains:

CUMULUS = {
    'HEADERS': (
        (r'.*\.(eot|otf|woff|ttf)$', {
            'Access-Control-Allow-Origin': '*'
        }),
    )
}

Requirements

  • Django>=1.2
  • python-cloudfiles >= 1.7.9

Tests

To run the tests, clone the github repo, install tox and invoke tox from the clone’s root. This will upload two very small files to your container and delete them when the tests have finished running.

Issues

To report issues, please use the issue tracker at https://github.com/richleland/django-cumulus/issues.