从不同的控制器调用创建操作

Question

我想从 bookings#new 和 rooms#show 创建一个预订。当我尝试从 bookings#new 创建它时它有效，但是当我尝试从 rooms#show 创建它时它显示错误：

1 error prohibited this booking from being saved, room must exist.

这是我使用的代码：

预订控制器：

def create
  if @room          
    @room = Room.find(params[:room_id])
    @booking = @room.bookings.create(booking_params)
    if @booking.save
      redirect_to room_path(@room)
    else
      render :new
    end        
  else 
    @booking = Booking.new(booking_params)
    respond_to do |format|
      if @booking.save
        format.html { redirect_to @booking, notice: 'Booking was successfully created.' }
        format.json { render :show, status: :created, location: @booking }
      else
        format.html { render :new }
        format.json { render json: @booking.errors, status: :unprocessable_entity }
      end
    end
  end
end

views/rooms/show.html.erb

<h2>book this room:</h2>
<%= form_with(model: [ @room, @room.bookings.build ], local: true) do |form| %>
  <p>
    <%= form.label :traveller %>
    <%= form.text_field :traveller %>
  </p>

 <p>
    <%= form.label :startfrom %>
    <%= form.datetime_select :startfrom %>
  </p>

  <p>
    <%= form.label :endsat %>
    <%= form.datetime_select :endsat %>
  </p>

  <p>
    <%= form.label :bookingref %>
    <%= form.text_field :bookingref %>
  </p>

  <p>
    <%= form.submit %>
  </p>
<% end %>

Answer 1

你的错误在控制器的 if-else 中。您在定义 @room 之前检查它，因此它始终为零。应该是：

def create
  # use find_by here, otherwise you get RecordNotFound error
  @room = Room.find_by(id: params[:room_id])
    if @room
      # use build, because create saves the instance
      @booking = @room.bookings.build(booking_params)
      if @booking.save
        redirect_to room_path(@room)
      else
        # I suppose you don't want render bookings/new view here
        render 'books/show'
      end
    else 
      @booking = Booking.new(booking_params)
      respond_to do |format|
        # redirect and render logic goes here. BTW, do you really need json response format?
      end
    end
  end
end

此外，在房间中定义#show action

@booking = @room.bookings.build

并使用表单中的实例正确显示验证错误

form_with(model: [@room, @booking], local: true) do |form|

从不同的控制器调用创建操作

Call create action from different controller

ruby-on-rails

ruby-on-rails-5.2