我有一个用户和帖子的rails应用程序，我添加了另一个叫做频道的sacffold，现在关系就像用户可以创建帖子和频道，频道属于用户，帖子属于用户和频道，添加用户ID我创建了一个迁移渠道，一切看起来不错，但我在创建频道时收到此错误。 (Here is a screenshot of the exact error)
这是我在命令行上得到的：
Started POST "/channels" for 127.0.0.1 at 2017-12-16 13:30:32 +0530
Processing by ChannelsController#create as HTML
Parameters: {"utf8"=>"✓", "authenticity_token"=>"IJvvEe+TR6buacH5UwtiLSJglMkq7a+Q4x7VOTqALcGka4j6tG7lPi/7kYnCQ/nzmO7PNe2eSan3sBz9NqKV2g==", "channel"=>{"name"=>"dhfkdhfk", "description"=>"jdfjdfh", "tagline"=>"jdfjdfhj", "category"=>"jdfjdf", "avatar"=>""}, "commit"=>"Create Channel"}
User Load (2.3ms) SELECT "users".* FROM "users" WHERE "users"."id" = $1 ORDER BY "users"."id" ASC LIMIT 1 [["id", 1]]
(2.6ms) BEGIN
(1.8ms) ROLLBACK
Rendered channels/_form.html.erb (11.5ms)
Rendered channels/new.html.erb within layouts/application (13.3ms)
Rendered layouts/_avatar_dropdown.html.erb (7.4ms)
Rendered layouts/_header.html.erb (12.6ms)
Rendered layouts/_alert_messages.html.erb (0.5ms)
Completed 200 OK in 367ms (Views: 345.3ms | ActiveRecord: 6.7ms)
Add_user_id_to_channel.rb
class AddUserIdToChannels < ActiveRecord::Migration
def change
add_reference :channels, :user, index: true, foreign_key: true
end
end
channel.rb
class Channel < ActiveRecord::Base
validates :name, :description, :user_id, presence: true
belongs_to :user
has_many :posts, dependent: :destroy
end
user.rb
class User < ActiveRecord::Base
# Include default devise modules. Others available are:
# :confirmable, :lockable, :timeoutable and :omniauthable
devise :database_authenticatable, :registerable,
:recoverable, :rememberable, :trackable, :validatable,
:omniauthable, :omniauth_providers => [:facebook, :twitter, :google_oauth2]
act_as_mentionee
validates :username, presence: true
validate :avatar_image_size
has_many :posts, dependent: :destroy
has_many :channels, dependent: :destroy
has_many :responses, dependent: :destroy
has_many :likes, dependent: :destroy
after_destroy :clear_notifications
after_commit :send_welcome_email, on: [:create]
mount_uploader :avatar, AvatarUploader
include UserFollowing
include TagFollowing
include SearchableUser
include OmniauthableUser
private
# Validates the size on an uploaded image.
def avatar_image_size
if avatar.size > 5.megabytes
errors.add(:avatar, "should be less than 5MB")
end
end
# Returns a string of the objects class name downcased.
def downcased_class_name(obj)
obj.class.to_s.downcase
end
# Clears notifications where deleted user is the actor.
def clear_notifications
Notification.where(actor_id: self.id).destroy_all
end
def send_welcome_email
WelcomeEmailJob.perform_later(self.id)
end
end
user_controller
class UsersController < ApplicationController
before_action :authenticate_user!, only: [:edit, :update]
before_action :authorize_user, only: [:edit, :update]
before_action :set_user, only: [:show, :edit, :update]
def show
@followers_count = @user.followers.count
@following_count = @user.following.count
@latest_posts = @user.posts.latest(3).published
@recommended_posts = @user.liked_posts.latest(4).published.includes(:user)
end
def update
if @user.update(user_params)
redirect_to @user
else
render :edit, alert: "Could not update, Please try again"
end
end
private
def set_user
@user = User.find(params[:id])
end
def user_params
params.require(:user).permit(:description, :avatar, :location, :username)
end
def authorize_user
unless current_user.slug == params[:id]
redirect_to root_url
end
end
end
channel_controller
class ChannelsController < ApplicationController
before_action :set_channel, only: [:show, :edit, :update, :destroy]
before_action :authenticate_user!, except: [:show]
before_action :authorize_user, only: [:edit, :update, :destroy]
# GET /channels
# GET /channels.json
def index
@channels = Channel.all
end
# GET /channels/1
# GET /channels/1.json
def show
end
# GET /channels/new
def new
@channel = Channel.new
@channel = current_user.channels.build
@user = current_user
end
# GET /channels/1/edit
def edit
end
# POST /channels
# POST /channels.json
def create
@channel = current_user.channels.build(channel_params)
@channel = Channel.new(channel_params)
@user = current_user
respond_to do |format|
if @channel.save
format.html { redirect_to @channel, notice: 'Channel was successfully created.' }
format.json { render :show, status: :created, location: @channel }
else
format.html { render :new }
format.json { render json: @channel.errors, status: :unprocessable_entity }
end
end
end
# PATCH/PUT /channels/1
# PATCH/PUT /channels/1.json
def update
respond_to do |format|
if @channel.update(channel_params)
format.html { redirect_to @channel, notice: 'Channel was successfully updated.' }
format.json { render :show, status: :ok, location: @channel }
else
format.html { render :edit }
format.json { render json: @channel.errors, status: :unprocessable_entity }
end
end
end
# DELETE /channels/1
# DELETE /channels/1.json
def destroy
@channel.destroy
respond_to do |format|
format.html { redirect_to channels_url, notice: 'Channel was successfully destroyed.' }
format.json { head :no_content }
end
end
private
# Use callbacks to share common setup or constraints between actions.
def set_channel
@channel = Channel.find(params[:id])
end
# Never trust parameters from the scary internet, only allow the white list through.
def channel_params
params.require(:channel).permit(:name, :description, :tagline, :category, :avatar, :user_id)
end
def authorize_user
begin
@channel = current_user.channels.find(params[:id])
rescue
redirect_to root_url
end
end
end
在频道模型中，您通过添加在线状态强制提交“user_id”：true
validates :name, :description, :user_id, presence: true
所以你必须在参数中传递user_id。你可以通过在视图中添加hidden_filed来做到这一点
<%= f.hidden_field :user_id, value: @user %>
或者，如果您不需要'user_id'，请删除表单验证，如下所示：
validates :name, :description, presence: true
更改
@channel = current_user.channels.build(channel_params)
@channel = Channel.new(channel_params)
至
@channel = current_user.channels.build(channel_params)