模型关联(Rails 5 API)

Question

我有一个Character模型，它有一个CharClass和ClassPerks子模型。

目前，我通过手动分配数据来复制我的逻辑。

我的Character索引和创建：

def index

    @campaign = Campaign.find_by_id(params[:campaign_id])
    @characters = @campaign.characters
    render json: {
        characters: @characters
    }
end

def create
    @campaign = Campaign.find_by_id(params[:campaign_id])
    @charClass = CharClass.find_by_id(params[:character_char_class_id])
    @character = @campaign.characters.new(character_params)
    @character.char_class_id = params[:character_char_class_id]

    if @character.save!
        render status: 201, json: {

            message: "Successfull added this character to the campaign!",
            character_name: @character.character_name + ' the ' + @charClass.class_name,
            character_class: @charClass.class_name,
            character_level: @character.character_level,
            character_experience: @character.character_experience,
            character_gold: @character.character_gold,
            character_perks: get_names(@character.character_perks),
            character_image: @character.character_image

        }
    else
        render status: 404, json: {
            message: "Something went wrong: Check line 24 of the Character Controller"
        }
    end
end

我正在手动分配character_class和character_image，尽管这两者基于它们的character_class总是相同的。

在character.rb内部，我这样做是为了在创建后分配给他们：

    after_create :add_perks, :save_class

    def add_perks
        self.class_perks.each do |perk|
            self.character_perks.create(class_perk_id: perk.id)
        end
    end


    def save_class()
        case self.char_class_id
            when 1 # Mindthief
                self.character_image = "https://gloomhavenil.files.wordpress.com/2017/12/11849117_616974988445216_217288420_n.jpg?w=480"
                self.character_class = "Mindthief"
                self.save
            when 2 # Tinkerer
                self.character_image = "http://www.cephalofair.com/wp-content/uploads/2015/04/Quatryl-Tinkerer.jpg"
                self.character_class = "Tinkerer"
                self.save
            # when 'Sawbones'
            # else
        end
    end
end

它正在起作用，但我不知道如何更好地/适当地做这件事。我删除了无用的字段，但你会看到，下面，我已经建立了适当的关系。

  create_table "char_classes", force: :cascade do |t|
    t.string "class_name"
    t.string "class_image"
    t.string "class_perks"
    t.datetime "created_at", null: false
    t.datetime "updated_at", null: false
  end

 create_table "characters", force: :cascade do |t|
    t.string "character_class"
    t.string "character_image"
    t.integer "char_class_id"
    t.index ["campaign_id"], name: "index_characters_on_campaign_id"
    t.index ["char_class_id"], name: "index_characters_on_char_class_id"
  end

我可以做Character.first.char_class.class_name，我会得到适当的结果；所以我又回到假设我遵循的方法是非常不正确的。

Answer 1

您需要使用ActiveModelSerializers (AMS)来基于类的实例序列化您的json响应。

class CampaignsController < ApplicationController
  def index
    render json: { characters: campaign.characters }
  end

  def create
    @character = campaign.characters.new(character_params.merge(char_class_id: char_class.id))

    if @character.save!
        render json: @character, serializer: CharacterSerializer, status: 201 # This should automatically be formatted by AMS
    else
        not_found('Something went wrong: Check line 24 of the Character Controller')
    end
  end

  private

  def campaign
    @campaign ||= Campaign.find_by_id(params[:campaign_id])
  end

  def char_class
    @charClass ||= CharClass.find_by_id(params[:character_char_class_id])
  end
end

字符类的AMS类应该是这样的

class CharacterSerializer < ActiveModel::Serializer
  attributes :message, :character_name, :character_class, :character_level, :character_experience, :character_gold, :character_perks, :character_image

  def message
    'Successfull added this character to the campaign!'
  end

  def character_name
    return object.character_name + ' the ' + character_class # check the associations
  end

  def character_class
    object.charClass.class_name
  end

  def character_perks
    # Unsure what this get names methods does so im leaving it for you to refactor
    get_names(object.character_perks),
  end

end

还将此添加到您的ApplicationController中

class ApplicationController < ActionController::Base

  # Add this to your application controller

  def not_found(message = nil)
    render json: { message }, status: 404
  end

end

我将根据您的信息更新重构的模型类。希望这能帮上忙。