如果你正在使用RABL，你可以使用JSON.pretty_generate来配置它:

class PrettyJson
  def self.dump(object)
    JSON.pretty_generate(object, {:indent => "  "})
  end
end

Rabl.configure do |config|
  ...
  config.json_engine = PrettyJson if Rails.env.development?
  ...
end

使用JSON的一个问题。pretty_generate是JSON模式验证器将不再满意您的datetime字符串。你可以在config/initializers/rabl_config中修正这些问题。rb:

ActiveSupport::TimeWithZone.class_eval do
  alias_method :orig_to_s, :to_s
  def to_s(format = :default)
    format == :default ? iso8601 : orig_to_s(format)
  end
end

如果你想:

自动美化应用程序中所有传出的JSON响应。 避免污染Object#to_json/#as_json 避免使用中间件解析/重新呈现JSON(讨厌!) 用铁路的方式去做!

然后……为JSON替换ActionController::Renderer !只需将以下代码添加到您的ApplicationController:

ActionController::Renderers.add :json do |json, options|
  unless json.kind_of?(String)
    json = json.as_json(options) if json.respond_to?(:as_json)
    json = JSON.pretty_generate(json, options)
  end

  if options[:callback].present?
    self.content_type ||= Mime::JS
    "#{options[:callback]}(#{json})"
  else
    self.content_type ||= Mime::JSON
    json
  end
end

#At Controller
def branch
    @data = Model.all
    render json: JSON.pretty_generate(@data.as_json)
end

以下是我在搜索过程中从其他帖子中得到的解决方案。

这允许您根据需要将pp和jj输出发送到文件中。

require "pp"
require "json"

class File
  def pp(*objs)
    objs.each {|obj|
      PP.pp(obj, self)
    }
    objs.size <= 1 ? objs.first : objs
  end
  def jj(*objs)
    objs.each {|obj|
      obj = JSON.parse(obj.to_json)
      self.puts JSON.pretty_generate(obj)
    }
    objs.size <= 1 ? objs.first : objs
  end
end

test_object = { :name => { first: "Christopher", last: "Mullins" }, :grades => [ "English" => "B+", "Algebra" => "A+" ] }

test_json_object = JSON.parse(test_object.to_json)

File.open("log/object_dump.txt", "w") do |file|
  file.pp(test_object)
end

File.open("log/json_dump.txt", "w") do |file|
  file.jj(test_json_object)
end

看看Awesome Print吧。将JSON字符串解析为Ruby Hash，然后用ap显示它，如下所示:

require "awesome_print"
require "json"

json = '{"holy": ["nested", "json"], "batman!": {"a": 1, "b": 2}}'

ap(JSON.parse(json))

通过以上，你会看到:

{
  "holy" => [
    [0] "nested",
    [1] "json"
  ],
  "batman!" => {
    "a" => 1,
    "b" => 2
  }
}

Awesome Print还会添加一些Stack Overflow无法显示的颜色。

# example of use:
a_hash = {user_info: {type: "query_service", e_mail: "my@email.com", phone: "+79876543322"}, cars_makers: ["bmw", "mitsubishi"], car_models: [bmw: {model: "1er", year_mfc: 2006}, mitsubishi: {model: "pajero", year_mfc: 1997}]}
pretty_html = a_hash.pretty_html

# include this module to your libs:
module MyPrettyPrint
    def pretty_html indent = 0
        result = ""
        if self.class == Hash
            self.each do |key, value|
                result += "#{key}: #{[Array, Hash].include?(value.class) ? value.pretty_html(indent+1) : value}"
            end
        elsif self.class == Array
            result = "[#{self.join(', ')}]"
        end
        "#{result}"
    end

end

class Hash
    include MyPrettyPrint
end

class Array
    include MyPrettyPrint
end