ActionController::ParameterMissing (param is missing or the value is empty:)

Question

I studied the rails tutorial by Michael Hartl and I'd like to add new service to this app.

Although I created new model, controller and views, the following error appeared when I submit f.submit "Create my schedule" in _schedule_form.html.erb .

This error may be caused by strong parameter, I guess.

It would be appreciated if you could give me any suggestion.

ActionController::ParameterMissing (param is missing or the value is empty: schedule):
  app/controllers/schedules_controller.rb:30:in `schedule_params'
  app/controllers/schedules_controller.rb:9:in `create'

class SchedulesController < ApplicationController
  before_action :logged_in_user, only: [:create, :destroy]

  def new
    @schedule = Schedule.new
  end

  def create
    @schedule = current_user.schedules.build(schedule_params)
    if @schedule.save
      flash[:success] = "schedule created!"
      redirect_to root_url
    else
      render 'new'
    end
  end

...

  private

    def schedule_params
      params.require(:schedule).permit(:title)
    end

end

<div class="row">
  <div class="col-md-12">
    <p>Create schedule (<%= current_user.name %>)</p>
    <%= render "schedule_form" %>
  </div>
</div>

<%= form_for(@schedule) do |f| %>
  <%= render 'shared/error_messages', object: f.object %>
  <div class="input-group">
    <span class="input-group-addon">Title</span>
    <input type="text" class="form-control">
  </div>
  <br>
  <%= f.submit "Create my schedule", class: "btn btn-primary" %>
  <br>
<% end %>

Answer 1

The problem is that you're manually rendering the form input fields. The input field has to have a specific name for the params to get generated properly. In your case, you'd need something like:

<%= f.text_field :title %>

Have a look at the form helpers documentation for more details.

Answer 2

You're not building the form with the Rails helper method and so it isn't naming your input properly. Use the text field helper:

<%= f.text_field :title %>

Answer 3

You might be missing "schedule" in your params or it is empty. As I can see you are using direct html

     <input type="text" class="form-control">

instead use rails way of using form builder object for eg

    f.input :title, class: 'form-control'

or if you still want to use direct html use this instead

   <input type="text" class="form-control" name="schedule[title]">

Hope this helps