Json generation for collection of decorated objects about draper

[tden012]

This comment is a bit late, but I thought I'd add a solution that didn't involve forking. As mentioned by angelim, it's possible to create an ApplicationDecorator in order to add the methods necessary to add decorator methods to json. This is what mine looks like (it's more or less a complete copy of angelim's code)

class ApplicationDecorator < Draper::Decorator
  def as_json(options = {})
    as_decorated_json(options)
  end

  def to_json(options = {})
    as_json(options)
  end

  def as_decorated_json(options = {})
    model.as_json(options).merge(decorated_attributes(options))
  end

  def decorated_attributes(options = {})
    method_names = Array.wrap(options[:decorated_methods]).map { |n| n.to_s if respond_to?(n.to_s) }.compact
    Hash[method_names.map { |n| [n, send(n)] }].tap do |attrs|
      decorate_relations(attrs, options) if options[:decorated_include]
    end
  end

  def add_decorated_methods(options, method_names = [])
    options[:decorated_methods] = options[:decorated_methods] ? options[:decorated_methods] : []
    options[:decorated_methods].concat method_names
  end
end

Note the last method. This is useful if you want to make the model always render certain decorator methods in json. E.g.

class ModelDecorator < ApplicationDecorator
  delegate_all

  def my_decorator_method
    names[0]
  end

  def as_json(options = {})
    add_decorated_methods options, [:my_decorator_method]
    super options
  end
end

[steveklabnik]

This seems like pretty good advice, but it's not really an issue. How about adding a section about this to the README?

Since this isn't exactly a bug, I'm closing. Still good to have this text here, at least, thanks for writing it up. Always good to help future Googlers.

[kbaum]

I would like to add my decorator methods to the generated json. Is the best way to do that by using the fork from @angelim?

thx!

[steveklabnik]

I believe so, yes.