Add option to pretty print

[MarkMurphy]

It would be nice to be able to pretty print the json generated by jbuilder. The only solution I've found online to do this is pretty ugly:

 json_string = render_to_string formats: :json    
 json_object = JSON.parse(json_string)     
 render :json => JSON.pretty_generate(json_object)   

[rwz]

Not all MultiJson adapters support pretty_generate and there is no common interface for it. You could patch Jbuilder#target! method to conditionally give you pretty response when you want it to.

Something like this:

# config/initializers/jbuilder_pretty.rb

require "jbuilder"

class Jbuilder
  alias_method :_original_target, :target!

  def target!
    PRETTY_RESPONSE_ENABLED ? JSON.pretty_generate(@attributes) : _original_target
  end
end

[MarkMurphy]

Thanks!

[MarkMurphy]

In the context of an API. How might I change your_condition_goes_here so that I could specify JSON.pretty_generate per request?

[rwz]

# config/initializers/jbuilder_pretty.rb

require "jbuilder"

class Jbuilder
  alias_method :_original_target, :target!

  def prettify_response!
    @_pretty_response = true
  end

  def target!
    @_pretty_response ? JSON.pretty_generate(@attributes) : _original_target
  end
end

# app/views/your-jbuilder-template.json.jbuilder

if @i_want_responses_to_be_pretty
  json.prettify_response!
end

json.foo "bar"

# app/controllers/your_controller.rb

def your_action
  @i_want_responses_to_be_pretty = true
end

[MarkMurphy]

Thanks @rwz. For those who may find their way here, this is what my finial implementation ended up looking like:

# config/initializers/jbuilder_prettify.rb
require "jbuilder"

class Jbuilder
  ##
  # Allows you to set @prettify manually in your .jbuilder files. 
  # Example: 
  #   json.prettify true
  #   json.prettify false 
  #  
  attr_accessor :prettify

  alias_method :_original_target, :target!

  ##
  # A shortcut to enabling prettify.
  # Example:
  #   json.prettify!
  #
  def prettify!
    @prettify = true
  end

  def target!
    @prettify ? ::JSON.pretty_generate(@attributes) : _original_target
  end
end

# app/views/api/v1/users/show.json.jbuilder
json.prettify! if %w(1 yes true).include?(params["pretty"])

json.( @user, :id, :name, :created_at, :updated_at )

[erick8911]

Thanks! for some weird reason i just have to change

::MultiJson.dump(@attributes, pretty: true)
instead of
::JSON.pretty_generate(@attributes)

[jmoe]

FWIW, I just found a pretty simple solution for this. I'm using Jbuilder/MultiJson/Yajl. This initializer will default to pretty output unless you are in production.

https://gist.github.com/jmoe/02c7476adac24eddd969

[royratcliffe]

Alternatively, you can just stomp over Active Support's JSON-gem encoder implementation, just for development of course. Put the following in config/initializers.
active_support_pretty_json_encoding.rb

[veganstraightedge]

@MarkMurphy @rwz Thanks for putting this together years ago. It's 2018 and I just used this without a hitch! 🎉