Ruby On Rails Saving to Database Multiple Tables

Question

I'm new to Ruby on Rails and trying to learn it by doing one simple application. What i'm trying to do is to save the details to different tables in a DB using nested attributes. Im getting an unpermited parameters :locations error in my terminal.

here are my files..

State.rb

class State < ActiveRecord::Base
    has_many :locations
end

City.rb

class City < ActiveRecord::Base
    has_many :locations
end

Location.rb

class Location < ActiveRecord::Base
    belongs_to :user
    belongs_to :state
    belongs_to :city
end

User.rb

class User < ActiveRecord::Base
    has_many :locations
    accepts_nested_attributes_for :locations
end

User Controller.rb

class UserController < ApplicationController
  def new
  end
  def create
    p "======================="
    p params
    p "======================="
    p user_params
    p "-----------------------"
    @user = User.new(user_params)
    @user.save
    redirect_to @user
  end

  def update_city_select
    @cities = City.where(state_id: params[:state_id]).order(:name) unless params[:state_id].blank?
    respond_to do |format|
      format.html { render layout: false }
      format.js
    end
  end
  def show
    # @user = User.find(params[:id])
    # @location = Location.find(params[:id])
  end
  private
    def user_params
        params.require(:user).permit(:id,:firstname, :lastname,
            :locations_attributes=>[:id,:user_id,:state_id,:city_id]
            )
    end
end

new.html.erb

<html>
    <head></head>
    <body>

        <%= form_for :user, url: users_path do |j| %>
            <div id="first_name">
                <label>First Name</label>
                <div>
                    <%= j.text_field :firstname %>
                </div>
            </div>

            <div id="last_name">
                <label>Last Name</label>
                <div>
                    <%= j.text_field :lastname %>
                </div>
            </div>
            <%= j.fields_for :locations do |jl| %>
                <%= render 'location_fields', :j => jl %>
            <% end %>
            <div>
                <div id="submit">
                    <%= j.submit %>             
                </div>
            </div>  
        <%end%>

        <script type="text/javascript">
            $("#state_name").change(function() {
                var state = $('#state_name :selected').val();
                $.ajax({
                    url: '/student_profile/update_city_select',
                    type: 'GET',
                    data: {
                    state_id: state
                    },
                success: function(response) {
                    $('#city_name').html(response);                 
                    }
                });
            });
        </script>
    </body>
</html>

and _location_fields.html.erb

<div id="state_name">
    <label>Location[State]</label>
    <div>                   
        <%= j.select :state_id, State.all.map{|j| [j[:name], j[:id]]} %>
    </div>
</div>
<div>
    <label>City</label>
    <div id="city_name">
        <%= j.select :city_id, {} ,{} %>
    </div>
</div>

I have this 4 fields in my page. First Name and Last Name gets saved to the User table. What im trying to achieve is that i want to save the state_id and city_id to locations table. State and City tables have a set of Variables. State anD City are dropdown list. Upon selecting one state corresponding cities will be loaded to the Cities Dropdown.

Here is the output from terminal..

"======================="
{"utf8"=>"✓", "authenticity_token"=>"7zmznmSLQ+D/089mZLjrT0H784lsX1ERilyvP68jG4I=", "user"=>{"firstname"=>"Nidhin", "lastname"=>"Besole", "locations"=>{"state_id"=>"3"}}, "city_id"=>"28516", "commit"=>"Save User", "controller"=>"user", "action"=>"create"}
"======================="
Unpermitted parameters: locations
{"firstname"=>"Nidhin", "lastname"=>"Besole"}
"-----------------------"
Unpermitted parameters: locations

THanks in advance.

chumakoff · Accepted Answer · 2014-03-21T08:31:27.763

You can use an User instance (@user) to build the form. You are using :user symbol now. Your building form knows nothing about User model and passes locations parameters as locations instead of locations_attributes.

User Controller.rb

class UserController < ApplicationController
  def new
    @user = User.new
  end
  ...
end

new.html.erb

<html>
    <head></head>
    <body>

        <%= form_for @user do |j| %>
        ...

Solution 2:

You can just pass :locations_attributes symbol to fields_for helper instead of :locations symbol:

<%= j.fields_for :locations_attributes do |jl| %>

Ruby On Rails Saving to Database Multiple Tables

1 Answers1