Varnish
Explore how to implement server-side integration using Varnish as an Edge Side Includes (ESI) solution. Understand Varnish caching mechanisms, Docker deployment, and configuration language VCL for managing HTTP requests and improving microservice performance.
Introduction #
Varnish is a web cache and is used as an ESI implementation in the example.
Varnish is mainly used for optimizing web servers:
- It intercepts the HTTP requests to web servers.
- It then caches the responses.
- It forwards only those requests to the web servers that are not in the cache.
This improves performance.
Licence and support #
Varnish is licensed under a BSD license. The cache is mainly developed by Varnish Software, which also provides commercial support.
Caching with HTTP and HTTP headers #
Caching data correctly is not a trivial matter. Above all, the questions are when can content be retrieved from the cache and when does the data have to be retrieved from the web server ...