设计令牌身份验证：authenticate_user！ 工作错误

Question

If I add before_action :authenticate_user! to ApplicationController , I get an error:

ActionView::Template::Error (undefined method `name' for nil:NilClass):
    1: json.data @users, :name, :username

What comes from this file:

show.jbuilder

json.data @users, :name, :username

My controller:

users_controller.rb

class UsersController < ApplicationController

  before_action :authenticate_user!

  def index
    @users = User.all
  end

end

If I remove before_action :authenticate_user! everything works just fine, I get JSON object with the list of users.

Why does it happen? Device usually returns 401 , but devise_token_auth is trying to trigger my show and fails because can't access database. How to fix this weird behaviour?

Answer 1

Your controller is pretty idiosyncratic and your error is that you are sending a collection to a view that is built for a single resource.

In Rails the show action corresponds to viewing a single resource and usually relies on passing the ID via an :id parameter:

class UsersController < ApplicationController
  # GET /users
  def index
    @users = User.all
  end

  # GET /users/:id
  def show
    @user = User.find(params[:id])
  end
end

You don't need to explicitly call render either.

app/views/users/show.json.jbuilder:

json.(@user, :name, :username)

app/views/users/index.json.jbuilder:

json.comments @user do |json, user|
  json.(user, :name, :username)
end