Param is missing or the value is empty: class

Question

I'm trying to create a select, however I am getting this error:

ActionController::ParameterMissing in ClassesController#create

param is missing or the value is empty: class # Never trust parameters from the scary internet, only allow the white list through.

def class_params

params.require(:class).permit(:classe, :segmento_id)

end

end

I'm trying to create a select however the same is returning this error ... If it's a simple select. I'm using simple_form.

Someone help me please?

My form:

    <%= simple_form_for(@class) do |f| %>
  <%= f.error_notification %>

  <div class="form-inputs">
    <%= f.input :classe %>
    <%= f.collection_select :segmento_id, Segmento.all, :id, :categoria, prompt: 'Selecione uma Categoria', input_html: { class:'form-control' } %>
  </div>

  <div class="form-actions">
    <%= f.button :submit %>
  </div>
<% end %>

My Controller:

class ClassesController < ApplicationController
  before_action :set_class, only: [:show, :edit, :update, :destroy]


  # GET /classes
  # GET /classes.json
  def index
    @classes = Classe.all
  end

  # GET /classes/1
  # GET /classes/1.json
  def show
  end

  # GET /classes/new
  def new
    @class = Classe.new
  end

  # GET /classes/1/edit
  def edit
  end

  # POST /classes
  # POST /classes.json
  def create
    @class = Classe.new(class_params)

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

  # PATCH/PUT /classes/1
  # PATCH/PUT /classes/1.json
  def update
    respond_to do |format|
      if @class.update(class_params)
        format.html { redirect_to @class, notice: 'Classe was successfully updated.' }
        format.json { render :show, status: :ok, location: @class }
      else
        format.html { render :edit }
        format.json { render json: @class.errors, status: :unprocessable_entity }
      end
    end
  end

  # DELETE /classes/1
  # DELETE /classes/1.json
  def destroy
    @class.destroy
    respond_to do |format|
      format.html { redirect_to classes_url, notice: 'Classe was successfully destroyed.' }
      format.json { head :no_content }
    end
  end

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

    # Never trust parameters from the scary internet, only allow the white list through.
    def class_params
      params.require(:class).permit(:classe, :segmento_id)
    end

end

Dharmesh Rupani Dharmesh Rupani · Accepted Answer · 2016-06-09T21:02:59

there is typo in params.require(:classe)

def class_params
   params.require(:classe).permit(:classe, :segmento_id)
end

Param is missing or the value is empty: class

2 Answers