jiggneshhgohel/rabl-rails-directly-render-object.md

## rabl-rails-directly-render-object.md

      
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              rabl-rails-directly-render-object.md
            
          
    Using the suggestions in ccocchi/rabl-rails#88 (comment) I was able to resolve my problem  I described in ccocchi/rabl-rails#88 (comment) but I needed few customizations to be made.
Following is the list of customizations I made:


Created lib folder under app folder.


Created rabl-rails folder under app/lib folder.


Created renderers folder under app/lib/rabl-rails folder.


Created renderer.rb file under app/lib/rabl-rails folder.


Created hash_supporting_locals.rb file under app/lib/rabl-rails/renderers folder
and added following content to it


  module RablRails
    module Renderers
      module HashSupportingLocals
        include Renderers::Hash
        extend self

        #
        # Render a template.
        # Uses the compiled template source to get a hash with the actual
        # data and then format the result according to the `format_result`
        # method defined by the renderer.
        #
        def render(template, context, locals = nil)
          visitor = Visitors::ToHash.new(context)

          collection_or_resource = if template.data
            if context.respond_to?(template.data)
              context.send(template.data)
            else
              visitor.instance_variable_get(template.data)
            end
          end
           
          # Note: This is the line added to original implementation.
          collection_or_resource ||= locals[:resource] if locals

          render_with_cache(template.cache_key, collection_or_resource) do
            output_hash = if collection?(collection_or_resource)
              render_collection(collection_or_resource, template.nodes, visitor)
            else
              render_resource(collection_or_resource, template.nodes, visitor)
            end

            format_output(output_hash, root_name: template.root_name, params: context.params)
          end
        end
      end
    end
  end


Created json_supporting_locals.rb file under app/lib/rabl-rails/renderers folder and added following content to it

  module RablRails
    module Renderers
      module JSONSupportingLocals
        include Renderers::JSON
        include Renderers::HashSupportingLocals
        extend self

      end
    end
  end


Created library_extended.rb file under app/lib/rabl-rails folder and added following content to it

  module RablRails
    class LibraryExtended < Library

      # This is the customized-version of RENDERER_MAP in super class.
      RENDERER_MAP = begin
        h = Library::RENDERER_MAP.dup

        h.merge!(
          json: Renderers::JSONSupportingLocals,
          ruby: Renderers::HashSupportingLocals
        )

        h.freeze
      end

      # Overridden method so that `RENDERER_MAP` defined in this file
      # gets used by this method.
      def get_rendered_template(source, view, locals = nil)
        compiled_template = compile_template_from_source(source, view)
        format = view.lookup_context.formats.first || :json
        raise UnknownFormat, "#{format} is not supported in rabl-rails" unless RENDERER_MAP.key?(format)
        RENDERER_MAP[format].render(compiled_template, view, locals)
      end
    end
  end


Copied the contents of https://github.com/ccocchi/rabl-rails/blob/v0.4.3/lib/rabl-rails/renderer.rb file
and added them to the file app/lib/rabl-rails/renderer.rb.


Update app/lib/rabl-rails/renderer.rb by making following changes:


Replaced following
  require 'rabl-rails/renderers/hash'
  require 'rabl-rails/renderers/json'

WITH
  require 'rabl-rails/renderers/hash_supporting_locals'
  require 'rabl-rails/renderers/json_supporting_locals'


Added require 'rabl-rails/library_extended' as the last require statement.


In RablRails::Renderer::LookupContext class made following changes:


removed method rendered_format


added following method


  def formats
    [ @format ].map(&:to_sym)
  end


In render method replaced Library with LibraryExtended.


Finally you should have a ruby file in which there should be a method which has following line

  RablRails.render(serializable_object, <template_name>, view_path: <template_path>, format: :json)

At the top of that file add following code:
  require 'rabl-rails/renderer'

  module RablRails
    extend RablRails::Renderer
  end

and that method should work without needing any changes.