Simple_form和accepts_nested_attributes_for的问题

Question

I'm quite new with RoR so sorry if I say something not correct.

I have these models.

class Course < ApplicationRecord
  has_many :frequencies, inverse_of: :course
  belongs_to :subject, optional: true
  validates :start_date, presence: true
end

class Frequency < ApplicationRecord
  belongs_to :user
  belongs_to :course
  validates :course, presence: true
  validates_presence_of :course
  accepts_nested_attributes_for :user, :course
  has_many_attached :docs
end

The relationship between Course and Frequency is 1:N but, at the end, I use it as a 1:1 (things changed after defined the models).

This is the view app/views/frequencies/show.html.haml

    = simple_form_for @frequency, :url => frequencies_update_path(:id => @frequency.id) do |f|
            .panel.panel-primary
              .panel-heading
                %h4.panel-title= t 'frequencies.upd_frequency'
              .panel-body
                = f.simple_fields_for :user  do |u|
                  .row
                    .col-md-4
                      = u.label t 'frequencies.first_name'
                    .col-md-4
                      = u.input :first_name, :label => false, :disabled => true, :input_html => {:id => 'first_name'}
                  .row
                    .col-md-4
                      = u.label t 'frequencies.last_name'
                    .col-md-4
                      = u.input :last_name, :label => false, :disabled => true, :input_html => {:id => 'last_name'}
                      -#= u.hidden_field :id, value: @user_id
            .panel.panel-primary
              .panel-heading
                %h4.panel-title= t 'frequencies.course'
              .panel-body
                = f.simple_fields_for :course  do |u|
                  .row
                    .col-md-4
                      = u.label t 'frequencies.course_start_date'
                    .col-md-4
                      = u.input :start_date, :label => false, :disabled => (@frequency.validated? ? true : false), :input_html => {:id => 'course_start_date'}
    .
    .
    .
    = f.submit t('button.save'), :class => 'btn btn-primary ' + (current_user.role == $admin_role && @frequency.validated? ? 'disabled' : '')
= link_to t('button.cancel'), request.referer.present? ? request.referer : frequencies_index_path, :class => 'btn btn-default'

This is part of the frequencies_controller.rb

def update
    @frequency = Frequency.find params[:id]
    @course = Course.find @frequency.course_id
    if over_max_hours_in_a_day(frequency_params[:user_attributes][:id], @course)
        flash[:danger] = t('flash.max_hours')
        render :action => :show and return
    end
    if @course.update(frequency_params[:course_attributes])
      @frequency.docs.attach(frequency_params[:attach][:docs]) if (frequency_params[:attach].present? && frequency_params[:attach][:docs].present?)
      flash[:notice] = t('flash.upd')
      redirect_to :action => 'index' and return
    else
      flash[:danger] = @course.errors.full_messages.to_sentence
      render :action => :show and return
    end
  end


  def show
    @frequency = Frequency.find params[:id]
    @subjects = Subject.all
  end

I'm able to edit a course from the related frequency's view but I have some strange behaviours:

• when I save the validation process occurs but I have the error message only as flash message and not under the involved field (in others simpler views I have the message also under the field)
• when I edit some course's fields (from the frequency view) and after I click on the save button it calls the update action but, if it runs inside the over_max_hours_in_a_day if condition, I'm not able to stay on the same view with the modified fields precompiled (but I have the fields like it loads at the beginning show action)
• when I press the cancel button after a previous failed edit I remain on the same page instead of come back to the previous view (index view)

I'm not sure if this is due to accepts_nested_attributes_for on a belongs_to model, because I usually see it in a has_many model.

Rails 5 5.2.2

simple_form 4.1.0

Please, can you help me?

Thanks.

Answer 1

1. separate logic depending on the view (from show / index pages). Create 2 update methods
2. in case of error just render view again render :show OR render :index
3. I think it's better move logic of over_max_hours_in_a_day to model
4. for cancel button don't use referrer because after update it won't work. Pass exact back url using form locals or other way
5. if you want to hightligh fields - you must call .update , .save method on it with form parameters