Varnish caching in Plone

Reverse caching proxies like Varnish are a first-class citizen in Plone. In this session, we’re going to take a look at how to integrate Varnish into your Plone project, to increase performance and scalability.

We'll cover the basics of Varnish, learn how to set it up and configure. We'll also learn how to configure Plone for caching proxies, how to expose the right caching headers and how to correctly invalidate the cache when content updates happen.

VCL, the built-in programming language of Varnish, will be used to tailor the caching behavior to Plone's needs, and we'll also look at some deployment scenarios using traditional servers, in the Cloud, or on Kubernetes using the official Varnish Helm chart.

And at the end of the session, we’ll also cover some advanced scenarios that require the use of Varnish Enterprise.

The basics of Varnish, the way it behaves out of the box, the way it interacts with HTTP's built-in caching headers, and of course Varnish Configuration Language (VCL).

VCL is the built-in programming language of Varnish that allows you to customize the caching behavior to your exact needs. I'll focus a lot on that, because VCL will be used to ensure caching and cache invalidation happens according to Plone's expectations.

Cache invalidation is also important in this presentation, especially for Plone, which is a content-driven application. I'll show how to combine Plone configuration and VCL configuration to invalidate the right objects from the cache when content updates take place in Plone.

I'll also show the impact of using Volto as a frontend and how it requires some extra VCL code.

Deployment is important, I'll talk about standard Linux packages that are available, but also about Cloud images, about Docker containers & about Kubernetes orchestration using our Helm chart.

For users who want to take it to the next level, I'll introduce some Varnish Enterprise features. Don't worry, this won't be a sales pitch.