Mothership Varnish cache adapter for headless Shopware

This Shopware bundle adds a cache adapter for a varnish for headless shopware.
If activated, it automatically invalidates a varnish cache when a cache-tag gets invalidated in Shopware. Like this, an external frontend application can use an effective full page cache (FPC) together with a headless Shopware backend.

This bundle is meant to be used together with the corresponding nuxt module e.g. for Shopware-PWA. Nevertheless, it can be used without the nuxt module, if the headless application sets cache tags in another way.

This currently obviously only works on self-hosted Shopware instances, as you need to be able to install the bundle.

Installation

Make sure Composer is installed globally, as explained in the installation chapter of the Composer documentation.

Applications that use Symfony Flex

Open a command console, enter your project directory and execute:

$ composer require mothership/headless-shopware-varnish-cache

Applications that don't use Symfony Flex

Step 1: Download the Bundle

Open a command console, enter your project directory and execute the following command to download the latest stable version of this bundle:

$ composer require mothership/headless-shopware-varnish-cache

Step 2: Enable the Bundle

Then, enable the bundle by adding it to the list of registered bundles in the config/bundles.php file of your project:

// config/bundles.php

return [
    // ...
    Mothership\HeadlessShopwareVarnishCacheBundle\HeadlessShopwareVarnishCacheBundle::class => ['all' => true],
];

Step 3: Configuration

First add the configuration file:

# www/config/packages/cache.yml
headless_shopware_varnish_cache:
  enabled: "%env(bool:HEADLESS_VARNISH_ACTIVE)%"
  reverse_proxy:
    hosts: "%env(csv:HEADLESS_VARNISH_HOSTS)%"
    max_parallel_invalidations: 3
    ban_method: "BAN"
    tag_flush_threshold: 100
    use_xkey: true # requires Varnish module xkey
    xkey_chunksize: 50 # optional, default: 50

As you can see, two environment variables are used:

• HEADLESS_VARNISH_ACTIVE: 1 or 0 to activate/deactivate
• HEADLESS_VARNISH_HOSTS: Comma-separated list of varnish hosts, e.g. "https://www.mydomain.de ,https://www.mydomain.com"

Example Varnish configuration

See a stripped down example Varnish configuration here.
There is also an example available which only uses xkeys here.

Disclaimer: this is not a production ready configuration file and stripped down to show the essential parts for the caching solution!

Usage

After installation and activation the module automatically invalidates the varnish cache at the configured hosts when a cache-tag gets invalidated in Shopware.
For example if a product changes, Shopware by default invalidates a cache-tag for this product. Like this all pages that contain this product get invalidated too and therefore are always up-to-date.

CLI-Command to manually flush the cache

bin/console varnish:invalidate

• by default, it flushes the whole cache for all hosts
• --tags : Comma separated tags to clear
• --regex : Regex to match URLs which should be flushed

Flush manually via curl

Using the xkeys version

Usecase	Command	Description
single URL	curl -X BAN https://www.domain.de/my/path	Only the specified URL gets flushed
whole domain	curl -X BAN -H 'xkey: all' https://www.domain.de	Flush all URLs on the specified host
single cache-tag	curl -X BAN -H 'xkey: product-<ID>' https://www.domain.de	Flush all sites (on all hosts) with cache-tag "product-"

Using the custom-header version

Usecase	Command	Description
single URL	curl -X BAN https://www.domain.de/my/path	Only the specified URL gets flushed
whole host	curl -X BAN -H 'X-Cache-Tags: all' https://www.domain.de	Flush all URLs on the specified host
single cache-tag	curl -X BAN -H 'X-Cache-Tags: product-<ID>' https://www.domain.de	Flush all sites with cache-tag "product-" on this host