Ruby on Rails中，如何将用户ID转换为长尾？

本文共计1053个文字，预计阅读时间需要5分钟。

我正在使用Devise来管理用户，目标是使用自定义的记录保存当前用户。我尝试将当前用户保存到控制器或表单中，但所有方式都失败了！感谢大家的帮助。我的记录模型类名为Record A。

我正在使用Devise来管理用户,我的目标是使用创建的记录保存当前用户.

我试图将当前用户保存在控制器或_form中,但无论哪种方式都失败了！

感谢大家的帮助.

我的记录模型

class Record < ActiveRecord::Base #Associations belongs_to :user # Validations validates :title, :user, presence: true end

我的记录控制器

class RecordsController < ApplicationController before_action :find_record, only: [:show, :edit, :update, :destroy] def create @record = Record.new(record_params) if @record.save redirect_to @record else @records = Record.all render 'index' end end def update if @record.update(record_params) flash[:notice] = "The record was updated successfully" redirect_to @record else render 'edit' end end private def find_record @record = Record.find(params[:id]) end def record_params params.require(:record).permit(:title, :description, :user_id).merge(user: current_user) # as suggested end end

我的Rspec

require 'rails_helper' describe RecordsController do let(:record) { create(:record) } let(:user) { create(:user) } let(:title) { "Some title I would like to put in my record" } let(:description) { "description I would like to put in my record" } describe "#create" do it "creates a new record with the given title and description" do expect do post :create, record: { title: title, description: description, user_id: user } end.to change { Record.count }.by(1) expect(response).to redirect_to(assigns[:record]) expect(assigns[:record].title).to eq(title) expect(assigns[:record].description).to eq(description) end it "fails to create a record and returns to the index page" do expect(post :create, record: { description: description }).to render_template(:index) expect(assigns[:records]).to eq(Record.all) end end describe "#update" do it "find the records and sets the new given values" do put :update, { id: record.id, record: { title: title, description: description } } record.reload expect(record.title).to eq(title) expect(record.description).to eq(description) expect(flash[:notice]).to eq("The record was updated successfully") end it "fails to create a record and returns to the edit page" do expect(put :update, { id: record.id, record: { title: "" } }).to render_template(:edit) end end end

现在,当前用户被保存,Rspec会在创建和更新时抛出错误：

1) RecordsController#create creates a new record with the given title and description Failure/Error: post :create, record: { title: title, description: description, user_id: user } NoMethodError: undefined method `authenticate' for nil:NilClass # ./app/controllers/records_controller.rb:42:in `record_params' # ./app/controllers/records_controller.rb:9:in `create' # ./spec/controllers/records_controller_spec.rb:36:in `block (4 levels) in <top (required)>' # ./spec/controllers/records_controller_spec.rb:35:in `block (3 levels) in <top (required)>' # -e:1:in `<main>' 2) RecordsController#create fails to create a record and returns to the index page Failure/Error: expect(post :create, record: { description: description }).to render_template(:index) NoMethodError: undefined method `authenticate' for nil:NilClass # ./app/controllers/records_controller.rb:42:in `record_params' # ./app/controllers/records_controller.rb:9:in `create' # ./spec/controllers/records_controller_spec.rb:46:in `block (3 levels) in <top (required)>' # -e:1:in `<main>' 3) RecordsController#update find the records and sets the new given values Failure/Error: put :update, { id: record.id, record: { title: title, description: description } } NoMethodError: undefined method `authenticate' for nil:NilClass # ./app/controllers/records_controller.rb:42:in `record_params' # ./app/controllers/records_controller.rb:20:in `update' # ./spec/controllers/records_controller_spec.rb:62:in `block (3 levels) in <top (required)>' # -e:1:in `<main>' 4) RecordsController#update fails to create a record and returns to the edit page Failure/Error: expect(put :update, { id: record.id, record: { title: "" } }).to render_template(:edit) NoMethodError: undefined method `authenticate' for nil:NilClass # ./app/controllers/records_controller.rb:42:in `record_params' # ./app/controllers/records_controller.rb:20:in `update' # ./spec/controllers/records_controller_spec.rb:72:in `block (3 levels) in <top (required)>' 要添加bo-oz的答案(应该可以使用),你还需要查看 foreign keys.尝试在记录表单中设置record_id根本不起作用,我认为在你对系统如何工作的解释中表现出误解这项重要的技术.

具体而言,您需要确保在保存新记录之前填充了user_id属性.这是一个关系数据库规范,而不是Rails：

每次在Rails中创建关联时,都必须在数据库中设置外键以启用ActiveRecord(Rails中的对象关联构建器)将适当的数据组合在一起：

#app/models/user.rb class User < ActiveRecord::Base has_many :records end #app/models/record.rb class Record < ActiveRecord:Base #see diagram above -- this has to have user_id in the schema :) belongs_to :user end

–

您遇到的问题是您在创建记录时没有设置用户外键.

您的记录表应该有一个user_id外键,这样当Rails拉出一个Record对象时,它就能找到与之关联的用户.

正如bo-oz解释的那样,你可以通过设置@ record.user来实现这一点,你也可以在params中设置它：

#app/controllers/records_controller.rb class RecordsController < ApplicationController def create @record = Record.new record_params @record.save .......... end private def record_params params.require(:record).permit(......).merge(user: current_user) end end

这两个答案都会在新的Record对象中设置适当的外键.