Many websites use a frontend cache such as Varnish, Squid, Cloudflare or CloudFront to gain extra performance. The downside of using a frontend cache though is that they don't respond well to updating content and will often keep an old version of a page cached after it has been updated.
The ``wagtailfrontendcache`` module provides a set of signal handlers which will automatically purge the cache whenever a page is published or deleted. These signal handlers are automatically registered when the ``wagtail.contrib.frontend_cache`` app is loaded.
Add a new item into the ``WAGTAILFRONTENDCACHE`` setting and set the ``BACKEND`` parameter to ``wagtail.contrib.frontend_cache.backends.HTTPBackend``. This backend requires an extra parameter ``LOCATION`` which points to where the cache is running (this must be a direct connection to the server and cannot go through another proxy).
Set ``WAGTAILFRONTENDCACHE_LANGUAGES`` to a list of languages (typically equal to ``[l[0] for l in settings.LANGUAGES]``) to also purge the urls for each language of a purging url. This setting needs ``settings.USE_I18N`` to be ``True`` to work. Its default is an empty list.
Firstly, you need to register an account with Cloudflare if you haven't already got one. You can do this here: `Cloudflare Sign up <https://www.cloudflare.com/sign-up>`_
To use an account-wide API key, find the key `as described in the Cloudflare documentation <https://support.cloudflare.com/hc/en-us/articles/200167836-Managing-API-Tokens-and-Keys#12345682>`_ and specify ``EMAIL`` and ``API_KEY`` parameters.
To use a limited API token, `create a token <https://support.cloudflare.com/hc/en-us/articles/200167836-Managing-API-Tokens-and-Keys#12345680>`_ configured with the 'Zone, Cache Purge' permission and specify the ``BEARER_TOKEN`` parameter.
A ``ZONEID`` parameter will need to be set for either option. To find the ``ZONEID`` for your domain, read the `Cloudflare API Documentation <https://api.cloudflare.com/#getting-started-resource-ids>`_
Within Amazon Web Services you will need at least one CloudFront web distribution. If you don't have one, you can get one here: `CloudFront getting started <https://aws.amazon.com/cloudfront/>`_
Add an item into the ``WAGTAILFRONTENDCACHE`` and set the ``BACKEND`` parameter to ``wagtail.contrib.frontend_cache.backends.CloudfrontBackend``. This backend requires one extra parameter, ``DISTRIBUTION_ID`` (your CloudFront generated distribution id).
Configuration of credentials can done in multiple ways. You won't need to store them in your Django settings file. You can read more about this here: `Boto 3 Docs <https://boto3.readthedocs.org/en/latest/guide/configuration.html>`_
In case you run multiple sites with Wagtail and each site has its CloudFront distribution, provide a mapping instead of a single distribution. Make sure the mapping matches with the hostnames provided in your site settings.
In most cases, absolute URLs with ``www`` prefixed domain names should be used in your mapping. Only drop the ``www`` prefix if you're absolutely sure you're not using it (e.g. a subdomain).
| azure-identity_ | No | Obtaining credentials. It's optional if you want to specify your own credential using a ``CREDENTIALS`` setting (more details below). |
| azure-mgmt-resource_ | No | For obtaining the subscription ID. Redundant if you want to explicitly specify a ``SUBSCRIPTION_ID`` setting (more details below). |
Add an item into the ``WAGTAILFRONTENDCACHE`` and set the ``BACKEND`` parameter to ``wagtail.contrib.frontend_cache.backends.AzureCdnBackend``. This backend requires the following settings to be set:
*``RESOURCE_GROUP_NAME`` - the resource group that your CDN profile is in.
*``CDN_PROFILE_NAME`` - the profile name of the CDN service that you want to use.
*``CDN_ENDPOINT_NAME`` - the name of the endpoint you want to be purged.
By default the credentials will use ``azure.identity.DefaultAzureCredential``. To modify the credential object used, please use ``CREDENTIALS`` setting. Read about your options on the `Azure documentation <https://docs.microsoft.com/en-us/azure/developer/python/azure-sdk-authenticate>`_.
..code-block:: python
from azure.common.credentials import ServicePrincipalCredentials
Another option that can be set is ``SUBSCRIPTION_ID``. By default the first encountered subscription will be used, but if your credential has access to more subscriptions, you should set this to an explicit value.
Azure Front Door
^^^^^^^^^^^^^^^^
With `Azure Front Door <https://azure.microsoft.com/en-gb/services/frontdoor/>`_ you will need a Front Door instance with caching enabled.
| azure-identity_ | No | Obtaining credentials. It's optional if you want to specify your own credential using a ``CREDENTIALS`` setting (more details below). |
| azure-mgmt-resource_ | No | For obtaining the subscription ID. Redundant if you want to explicitly specify a ``SUBSCRIPTION_ID`` setting (more details below). |
Add an item into the ``WAGTAILFRONTENDCACHE`` and set the ``BACKEND`` parameter to ``wagtail.contrib.frontend_cache.backends.AzureFrontDoorBackend``. This backend requires the following settings to be set:
*``RESOURCE_GROUP_NAME`` - the resource group that your Front Door instance is part of.
*``FRONT_DOOR_NAME`` - your configured Front Door instance name.
By default the credentials will use ``azure.identity.DefaultAzureCredential``. To modify the credential object used, please use ``CREDENTIALS`` setting. Read about your options on the `Azure documentation <https://docs.microsoft.com/en-us/azure/developer/python/azure-sdk-authenticate>`_.
..code-block:: python
from azure.common.credentials import ServicePrincipalCredentials
Another option that can be set is ``SUBSCRIPTION_ID``. By default the first encountered subscription will be used, but if your credential has access to more subscriptions, you should set this to an explicit value.
By default, Wagtail will only purge one URL per page. If your page has more than one URL to be purged, you will need to override the ``get_cached_paths`` method on your page type.
..code-block:: python
class BlogIndexPage(Page):
def get_blog_items(self):
# This returns a Django paginator of blog items in this section
