ActionView::DependencyTracker doesn't track jbuilder templates

[kipcole9]

Rails 4 doesn't dependency check jbuilder templates. This code (use as an initialiser, and is a minor edit of the supplied ERB tracker) adds a dependency tracker for jbuilder files to aid in russian doll caching strategies. Expect this will only work in Rails 4 (tested on Beta 1).

module ActionView
  class JBuilderTracker
    # Matches:
    #   json.partial! 'application/status'
    #   json.partial! @topic
    #   json.partial! topics
    #   json.partial! message.topics
    RENDER_DEPENDENCY = /
      partial!\s*                   # partial! call, followed by optional whitespace
      ([@a-z"'][@a-z_\/\."']+)      # the template name itself -- 1st capture
    /x

    def self.call(name, template)
      new(name, template).dependencies
    end

    def initialize(name, template)
      @name, @template = name, template
    end

    def dependencies
      Rails.logger.debug "Template Dependencies for #{name}: #{render_dependencies} + #{explicit_dependencies}"
      render_dependencies + explicit_dependencies
    end

  private
    attr_reader :name, :template

    def source
      template.source
    end

    def directory
      name.split("/")[0..-2].join("/")
    end

    def render_dependencies
      source.scan(RENDER_DEPENDENCY).
        collect(&:first).uniq.

        # partial! @topic           => "topics/topic"
        # partial! topics           => "topics/topic"
        # partial! message.topics   => "topics/topic"
        collect { |name| name.sub(/\A@?([a-z]+\.)*([a-z_]+)\z/) { "#{$2.pluralize}/#{$2.singularize}" } }.

        # partial! "headline"       => "message/headline"
        collect { |name| name.include?("/") ? name : "#{directory}/#{name}" }.

        # replace quotes from string renders
        collect { |name| name.gsub(/["']/, "") }
    end

    def explicit_dependencies
      source.scan(ActionView::DependencyTracker::ERBTracker::EXPLICIT_DEPENDENCY).flatten.uniq
    end
  end
end

ActiveSupport.on_load(:action_view) do
  ActiveSupport.on_load(:after_initialize) do
    require 'action_view/dependency_tracker'
    ActionView::DependencyTracker.register_tracker :jbuilder, ActionView::JBuilderTracker
  end
end

[rwz]

That looks great. Would you mind sending a pull-request?

Also, jbuilder does not support partial invokation with models like partial! @topic or partial! topics, so the code might be a lot easier.

[kipcole9]

Pavel, would happily do so but I'm not set up for Rails core development - will see what I can do but it will take a little time (and I have no formal test for this either yet). Will modify the code as you suggest to remove those two possibilities.

On 14/04/2013, at 12:18 PM, Pavel Pravosud notifications@github.com wrote:

That looks great. Would you mind sending a pull-request?

Also, jbuilder does not support partial invokation with models like partial! @topic or partial! topics, so the code might be a lot easier.

—
Reply to this email directly or view it on GitHub.

[vincentwoo]

Any movement on getting this into rails/cache_digests?

[rwz]

@vincentwoo not really. You can send a pull-request though :)

[vincentwoo]

Do you think this would be better living in rails/cache_digests or a monkey patch in rails/jbuilder?

[rwz]

Jbuilder has a quite specific partial rendering format calls so it better be a monkey-patch in Jbuilder

[dhh]

👍 to this.

[vincentwoo]

This didn't work for me. On jbuilder 2.0.0, changes in my dependent partials do not expire the parent's cache. They did, however, when using the supplied snippet as an initializer.

I am on Rails 3.2 and am using the json.partial 'partialname', :local => local syntax.

[vincentwoo]

Ah, I see now that this is likely because of

jbuilder/lib/jbuilder.rb

Line 332 in 0e2eb47

if defined?(Rails::VERSION::MAJOR) && Rails::VERSION::MAJOR == 4

.

Are you open to a PR patching this on 3.2 for people using the CacheDigests gem?

[rwz]

@vincentwoo I am. Want to send a pull-request?