Question

I am trying to update a model through JSON. Right now I am able to get the put method to execute.

From my browser console, I see this so I believed that my request did go through.

PUT http://localhost:3000/slot_allocations/1 [HTTP/1.1 200 OK  7ms]

However, I am not too sure how I could get Rails to accept the data I want to update and would appreciate it if someone could help me out.

This is my Jquery codes for Ajax request. dataToServer is the data I want to send to update the model.

var url = 'slot_allocations/'+alloc_id;
var dataToServer = {slot_allocation:{timeslot:timeslot, subject:subject,slot_allocation_id:alloc_id-1, group_id:"Group 2", lesson_type:"Tutorial"}}

$.ajax({
  type: "PUT",
  url: url, 
  dataType: "json",
  data:  JSON.stringify(dataToServer) , // message to send goes here
  success: function (data)
  {
  }
});

In my update method in the controller I have the following codes.

  def update
    @slot_allocation = SlotAllocation.find(params[:id])
    respond_to do |format|
      if @slot_allocation.update_attributes(params[:slot_allocation])
        format.html { redirect_to @slot_allocation, notice: 'Slot allocation was successfully updated.' }
        format.json { render :json=>@slot_allocation.as_json }
      else
        format.html { render action: "edit" }
        format.json { render json: @slot_allocation.errors, status: :unprocessable_entity }
        format.js  { render :js => @slot_allocation.errors, :status => :unprocessable_entity }
      end
    end
  end

And this is my as_json method. I am using it for my send request from the server to the client side but I am not too sure if I could use the same method to send information from the client to the server side.

  def as_json(options={}) 
  {
     :group_id =>self.group_index,
     :lesson_type =>self.lesson_type,
     :timeslot =>self.timeslot_id,
     :subject =>self.subject_id,
     :slot_allocation_id => self.slot_allocation_id
  }
  end

I would appreciate it if someone could guide me along as I am not too familiar with how I should get Rails to accept the parameters to update the model.

Answer 1

I believe you need to parse the JSON parameters first:

attributes = ActiveSupport::JSON.decode(params[:slot_allocation])
if @slot_allocation.update_attributes(attributes)
  ...
end

How do I parse JSON with Ruby on Rails?