How to use Strong_Parameters in Rails 4 with Mongoid, if it throws Unpermitted parameters: (model_name) error on nested attributes

Question

I am trying to use embedded relationship in MongoDB by using Mongoid with Rails 4.1.6. I have embedded an array of location data in my user model, as I will be adding user's location after every 5 minutes of interval.

This issue is:
I can add data to my database using IRB or Mongo Shell. But when I use my applications front end, it doesnt pass the embedded attributes. Ultimately document contains only user name which is the field of user model.

I tried to put the user_params in consol then I saw the below error :

Started POST "/users" for 127.0.0.1 at 2014-10-21 05:04:04 +0100 Processing by UsersController#create as HTML Parameters: {"utf8"=>"✓", "authenticity_token"=>"S5QKXuzEZID7eEjfhVWcYyLjEpi+Y3NVWt9cy/aEKOc=", "user"=>{"name"=>"Appuvaa4", "coord"=>{"lat"=>"40.23", "long"=>"33.33", "alt"=>"33.22"}}, "commit"=>"Create User"} Unpermitted parameters: coord

---

Unpermitted parameters: coord {"name"=>"Appuvaa4"}

---

I cant understand why it says Unpermitted parameters: coord, however I have used rails strong_parameters as below.

Please let me know whats wrong with my code.

I also read about the geospatial data storage in MongoDB which seems great. I would really appricaite if anyone could guide me any reference or links on How to store geospatial data with embedded document. So taht instead of storing data like this I will use geospatioal data storage as later I will also be implementing an algorithm over the stored data.

I suppose this issue is only related with Strong_parameters, so It wouldnt be problem if i change it to mongos Geospatial after this resolved.

`Private def user_params

   params.require(:user).permit(:name, 
                               :coords_attributes => [:lat, 
                                                      :long,:alt])

#I also Tried this 

params.require(:user).permit(:name, {:coords => [:lat, :long, :alt])
end `                                                        

But, both approach didnt work for me. Below is rest of my code:

User Controller

   class UsersController < ApplicationController
  before_action :set_user, only: [:show, :edit, :update, :destroy]


  def index
    @users = User.all
  end

  def show
    @users = User.all
  end

  def new
    @user = User.new
  end

  def edit
  end

  def create

    @user = User.new(user_params)
    puts '**********************************************'
    puts user_params

    puts '*****************************************'

    respond_to do |format|
      if @user.save
        format.html { redirect_to @user, notice: 'User was successfully created.' }
        format.json { render :show, status: :created, location: @user }
      else
        format.html { render :new }
        format.json { render json: @user.errors, status: :unprocessable_entity }
      end
    end

  end




  private
    # Use callbacks to share common setup or constraints between actions.
    def set_user
      @user = User.find(params[:id])
    end

    def user_params

        params.require(:user).permit(:name, 
                                   :coords_attributes => [:lat, 
                                                          :long, 
                                                          :alt])
    end

end

User.rb

    class User
  include Mongoid::Document
  include Mongoid::Attributes::Dynamic

  field :name


  embeds_many :coords, class_name: "User"
  #embeds_many :locations

  accepts_nested_attributes_for :coords
   #accepts_nested_attributes_for :locations


end

Coord.rb

   class Coord
  include Mongoid::Document
  field :lat
  field :long 
  field :alt

  embedded_in :user, :inverse_of => :coords

end

_form.html.erb

    <%= form_for(@user) do |f| %>
  <% if @user.errors.any? %>
    <div id="error_explanation">
      <h2><%= pluralize(@user.errors.count, "error") %> prohibited this user from being saved:</h2>

      <ul>
      <% @user.errors.full_messages.each do |message| %>
        <li><%= message %></li>
      <% end %>
      </ul>
    </div>
  <% end %>

  <div class="field">
    <%= f.label :name %><br>
    <%= f.text_field :name %>
  </div>

  <h3>Co-ordinates</h3>
  <%= f.fields_for :coord do |c| %>

    <div class="field">
    <%= c.label :Latitude %><br>
    <%= c.text_field :lat %>
  </div>
    <div class="field">
    <%= c.label :Longitude %><br>
    <%= c.text_field :long %>
  </div>
  <div class="field">
    <%= c.label :Altitude %><br>
    <%= c.text_field :alt %>
  </div>
  <% end %>

  <div class="actions">
    <%= f.submit %>
  </div>
<% end %>

Answer 1

I'm not sure if your posting JSON. This worked for me posting JSON on my issue.

You have:

params.require(:user).permit(:name, 
                                   :coords_attributes => [:lat, 
                                                          :long, 
                                                          :alt])

But needs to be:

params.require(:user).permit(:name, {:coords => [:lat, :long, :alt]})

Here's additional information on the issue.

https://github.com/rails/rails/blob/master/actionpack/lib/action_controller/metal/strong_parameters.rb#L246-L247