ActiveModel Serializers:如何序列化资源集合？

Question

我有一个bookmarks资源,并将其映射为json默认情况下在我的api命名空间下服务,如下所示routes.rb:

  namespace :api, defaults: {format: 'json'} do
    resources :bookmarks
    get ':username', to: 'users#index'
    get ':username/bookmarks/:id', to: 'users#show'
  end

我有一个Api::UsersController控制器和一个支持BookmarkSerializer,可以在单个书签资源上正常工作http://localhost:3000/api/emma_carter/bookmarks/87

但是当我尝试点击http://localhost:3000/api/emma_carter应该为用户拥有的所有书签提供服务时,我会遇到各种不同的错误.这是我的Api::UsersController

module Api
    class UsersController < ApplicationController
        respond_to :json

        def index
            user = User.find_by(username: params[:username])
            bookmarks = user.bookmarks
            render json: bookmarks
        end

        def show
            user = User.find_by(username: params[:username])
            bookmark = user.bookmarks.find_by(params[:id])
            render json: bookmark
        end
    end
end

该show方法有效,但索引方法给了我ArgumentError in Api::UsersController#index

wrong number of arguments (1 for 0)

更新:完整堆栈跟踪:https://gist.github.com/amite/b79fc42bfd73de5a07bd

截图

这是序列化器:

class BookmarkSerializer < ActiveModel::Serializer
    attributes :id, :url, :title, :domain, :notes, :image, :created, :username
    belongs_to :user

    def created
        object.created_at
    end

    def username
        user.username
    end
end

看看堆栈溢出的其他解决方案,我也尝试了我的index方法的其他版本:

        def index
            user = User.find_by(username: params[:username])
            bookmarks = user.bookmarks
            bookmarks.map { |bookmark| ::BookmarkSerializer.new(bookmark)}.to_json #updated line
        end

这给了我错误:

Missing template api/users/index, application/index with {:locale=>[:en], :formats=>[:json], :variants=>[], :handlers=>[:erb, :builder, :raw, :ruby, :coffee, :jbuilder]}.

接下来我的index方法的最后一个版本如下所示:

def index
  user = User.find_by(username: params[:username])
  bookmarks = user.bookmarks
  ActiveModel::ArraySerializer.new(bookmarks, each_serializer: ::BookmarkSerializer).to_json
end

这给了我错误 uninitialized constant ActiveModel::ArraySerializer

我究竟做错了什么？我正在使用rails 4.1.5和active_model_serializers 宝石的github版本.

gem 'active_model_serializers', github: 'rails-api/active_model_serializers'

更新:因为我试图输出bookmarks我也尝试使用单独的序列化程序 的集合,BookmarksSerializer但我收到相同的错误:ArgumentError in Api::UsersController#index wrong number of arguments (1 for 0)

UPDATE2:这是一种index方法的版本,它在某种意义上起作用,它以json格式呈现资源集合:

    def index
        user = User.find_by(username: params[:username])
        bookmarks = user.bookmarks

        respond_with bookmarks.to_json
    end

但这仍然没有使用 BookmarksSerializer

class BookmarksSerializer < ActiveModel::Serializer
    attributes :id, :title
end

它只输出默认哈希

完整的Gemfile

来源' https://rubygems.org '

# Bundle edge Rails instead: gem 'rails', github: 'rails/rails'
gem 'rails', '4.1.5'
# Use mysql as the database for Active Record
gem 'mysql2'
# Use SCSS for stylesheets
gem 'sass-rails', '~> 4.0.3'
# Use Uglifier as compressor for JavaScript assets
gem 'uglifier', '>= 1.3.0'
# Use CoffeeScript for .js.coffee assets and views
gem 'coffee-rails', '~> 4.0.0'
# See https://github.com/sstephenson/execjs#readme for more supported runtimes
# gem 'therubyracer',  platforms: :ruby

gem 'bourbon'
gem 'neat'
gem 'bitters'
gem 'refills'

gem 'wisper'
gem 'rails-ioc'
gem 'reform'
gem 'cells'
gem "pundit"

gem 'active_model_serializers', github: 'rails-api/active_model_serializers'

gem "font-awesome-rails"

gem 'simple_form'

# Use jquery as the JavaScript library
gem 'jquery-rails'

# Build JSON APIs with ease. Read more: https://github.com/rails/jbuilder
gem 'jbuilder', '~> 2.0'
# bundle exec rake doc:rails generates the API under doc/api.
gem 'sdoc', '~> 0.4.0',          group: :doc

group :development, :test do
  # Call 'debugger' anywhere in the code to stop execution and get a debugger console
  gem 'byebug'
  gem 'ffaker'
  gem 'pry-rails'

  gem 'capybara'
  gem 'factory_girl_rails'
  gem 'database_cleaner'
  gem 'capybara-webkit'
  gem 'rspec-cells'

  # Spring speeds up development by keeping your application running in the background. Read more: https://github.com/rails/spring
  gem 'spring'

  gem 'spring-commands-rspec'
  gem 'rspec-rails'
  gem 'guard-rspec'
  gem 'rb-fsevent' if `uname` =~ /Darwin/
end

# Use ActiveModel has_secure_password
gem 'bcrypt', '~> 3.1.7'

# Use unicorn as the app server
# gem 'unicorn'

# Use Capistrano for deployment
# gem 'capistrano-rails', group: :development

# Use debugger
# gem 'debugger', group: [:development, :test]

Answer 1

结果我需要包含宝石的v0.9

gem 'active_model_serializers', github: 'rails-api/active_model_serializers', branch: '0-9-stable'