Drupal 8 Module Development

Caching in block plugins

The render array we saw earlier was used as part of a Controller response. The latter is also known as the main content as it is the primary output of the page. On a normal Drupal installation, which uses the block module, this is included inside the Main page content block. We also said that setting a max-age of zero will bubble up to the top level render array causing the entire page to not be cached. This is true so far as the Controller response is concerned. Other blocks are still cached independently according to their own metadata.

In this book, you have already learned how we can create custom blocks, and we saw that they are also built using render arrays. Since this is the case, cache metadata can also be ...