Controller#Create - 找不到具有 'id'= 的用户

Question

我正在学习 web-dev 和 rails 并且已经被困了几天。

我有两个模型 - User 和 Property 并且有我认为正确的设置关联。

我要做的只是在user 已登录的情况下才允许创建property，并让property 属于该user。我得到的部分标志，但是当我去创建属性时，它给了我"Couldn't find User..." 错误。

我用了DB SQL Browser来验证有用户，有用户ID，所以不明白为什么登录的时候找不到。

感谢任何帮助。

---

控制器：

class PropertiesController < ApplicationController

before_action :authenticate_user!, only: [:new]

def index
    @properties = Property.all
end

def new 
    @property = Property.new
end

def create
    @user = User.find(params[:user_id])
    @property = @user.properties.new(property_params)
    respond_to do |format|
      if @property.save
        format.html { redirect_to @property, notice: 'Property was successfully created.' }
        format.json { render :show, location: @property}
      else
        format.html { render :new }
        format.json 
      end
    end
end

def show
    @property = Property.find(params[:id])
end

def edit

end

def update

end

def destroy

end

private

def property_params
        params.require(:property).permit(:street, :city, :province, :postal_code, :description, :picture)
end
end

数据库：

    ActiveRecord::Schema.define(version: 20160204211556) do

  create_table "properties", force: :cascade do |t|
t.string   "street"
t.string   "city"
t.string   "province"
t.string   "postal_code"
t.text     "description"
t.datetime "created_at",  null: false
t.datetime "updated_at",  null: false
t.integer  "property_id"
t.string   "picture"
t.integer  "user_id"
end

add_index "properties", ["property_id"], name: "index_properties_on_property_id", unique: true
add_index "properties", ["user_id"], name: "index_properties_on_user_id"

create_table "users", force: :cascade do |t|
t.string   "name"
t.string   "email"
t.datetime "created_at",                          null: false
t.datetime "updated_at",                          null: false
t.string   "password_digest"
t.string   "remember_digest"
t.string   "encrypted_password",     default: "", null: false
t.string   "reset_password_token"
t.datetime "reset_password_sent_at"
t.datetime "remember_created_at"
t.integer  "sign_in_count",          default: 0,  null: false
t.datetime "current_sign_in_at"
t.datetime "last_sign_in_at"
t.string   "current_sign_in_ip"
t.string   "last_sign_in_ip"
end

add_index "users", ["email"], name: "index_users_on_email", unique: true
add_index "users", ["reset_password_token"], name: "index_users_on_reset_password_token", unique: true

end

型号：

class Property < ActiveRecord::Base

belongs_to :user, dependent: :destroy 
mount_uploader :picture, PictureUploader
end

class User < ActiveRecord::Base
# Include default devise modules. Others available are:
# :confirmable, :lockable, :timeoutable and :omniauthable
devise :database_authenticatable, :registerable,
     :recoverable, :rememberable, :trackable, :validatable

has_many :properties

end

Answer 1

使用这个：

#config/routes.rb
resources :properties # -> url.com/properties/new

#app/controllers/properties_controller.rb
class PropertiesController < ApplicationController
  before_action :authenticate_user! #-> assuming you're using devise

  def new
    @property = current_user.properties.new
  end

  def create
    @property = current_user.properties.new property_params
    respond_to do |format|
      if @property.save
        format.html { redirect_to @property, notice: 'Property was successfully created.' }
        format.json { render :show, location: @property}
      else
        format.html { render :new }
        format.json 
      end
    end
  end

  private

  def property_params
     params.require(:property).permit(:street, :city, :province, :postal_code, :description)
  end
end

#app/views/properties/new.html.erb
<%= form_for @property do |f| %>
   <%= f.text_field :street %>
   <%= f.text_field :city %>
   <%= f.text_field :province %>
   <%= f.text_field :postal_code %>
   <%= f.text_field :description %>
   <%= f.submit %>
<% end %>

这将为current_user 创建一个新属性（假设您使用Devise 进行身份验证）

Answer 2

如果您能提供您的routes.rb 和错误消息，那就太好了。

我的猜测是，由于您在属性控制器中执行 @user = User.find(params[:user_id])，因此您的 user_id 不存在于参数中，因此 rails 无法找到 user_id。

在你的routes.rb，你可能需要

resources :users do 
   resources :properties
end

这样链接就会变成localhost:3000/users/1/properties/new 这样的链接，并且rails 可以找到user_id。

Answer 3

为什么不使用

@user = User.new(user_permit)

在你的 def 创建

然后将其添加到控制器的底部

private
def user_permit
    params[:user].permit!
end