cache.md

NoCMS Blocks

Cache

Since blocks are independent units of content, the standard Rails fragment cache seemed to fit well with them. That's why the render_block helper decides wether Rails cache should be used for rendering an individual block.

Cache for the blocks are configured at 3 levels:

1. The render_block helper may be called with a cache_enabled option set to true or false. This option will enable/disable the cache. This allow us to render a block without using the cache (maybe on a preview action).

  render_block block, cache: false

2. In the blocks configuration we can enable/disable the cache for all the blocks of a kind. We just have to add the cache_enabled setting.

NoCms::Blocks.configure do |config|

  config.block_layouts = {
    'default' => {
      template: 'default',
      fields: {
        title: :string,
        body: :text
      },
      cache_enabled: false
    }
  }
end

3. In the blocks configuration file we can enable/disable cache for all the blocks that doesn't have a cache_enabled setting. This configuration will be stored at NoCms::Blocks.cache_enabled

NoCms::Blocks.configure do |config|

  config.cache_enabled = true

end

As a summary:

  b = NoCms::Blocks::Block.new layout: 'default', title: 'Foo', description: 'Bar'
  NoCms::Blocks.cache_enabled # => true
  b.cache_enabled # => false, since the block configuration sets it to false
  render_block b # => This won't use fragment cache since this block layout have cache disabled

  b = NoCms::Blocks::Block.new layout: 'title-3_columns', title: 'Foo', description: 'Bar'
  NoCms::Blocks.cache_enabled # => true
  b.cache_enabled # => true, since this block configuration doesn't override NoCms::Block.cache_enabled
  render_block b # => This will use fragment cache since, by default, it's enabled for all blocks

  render_block b, cache_enabled: false # => This won't use fragment cache as the option in the helper overrides the block configuration