Edit Form Delete's a record from the database

问题

I Have a nested form that works pretty well in saving content to the database. The only problem is that when I click edit, the "grand-child" field is deleted from the database and thus I have to re-enter everything on that field. The normal behavior is on editing the previous content should be present.

I am using gem cocoon for nested forms simple_forms for my forms and ckeditor for richtext editing.

This is the server log when I click edit: notice: SQL (0.3ms) DELETE FROM "responses" WHERE "responses"."id" = $1 [["id", 53]] which happens every time I click edit on any entry in the exam model. Also notice that the question is selected but not deleted. Very strange.

    Started GET "/exams/24/edit" for 127.0.0.1 at 2015-11-09 16:59:40 +0300
Processing by ExamsController#edit as HTML
  Parameters: {"id"=>"24"}
  Exam Load (0.8ms)  SELECT  "exams".* FROM "exams" WHERE "exams"."id" = $1 LIMIT 1  [["id", 24]]
  Question Load (0.4ms)  SELECT "questions".* FROM "questions" WHERE "questions"."exam_id" = $1  [["exam_id", 24]]
  Response Load (0.4ms)  SELECT  "responses".* FROM "responses" WHERE "responses"."question_id" = $1 LIMIT 1  [["question_id", 44]]
   (0.1ms)  BEGIN
  SQL (0.3ms)  DELETE FROM "responses" WHERE "responses"."id" = $1  [["id", 53]]
   (15.3ms)  COMMIT
  Rendered exams/_response_fields.html.haml (2.4ms)
  Rendered exams/_response_fields.html.haml (2.1ms)
  Rendered exams/_question_fields.html.haml (32.6ms)
  Rendered exams/_response_fields.html.haml (0.7ms)
  Rendered exams/_response_fields.html.haml (0.6ms)
  Rendered exams/_question_fields.html.haml (8.1ms)

Exam model exam.rb

belongs_to :unit

has_many :questions, :dependent => :destroy

has_many :answers, :through => :questions

accepts_nested_attributes_for :questions, :reject_if => :all_blank, :allow_destroy => true

Quesions model

belongs_to :exam

has_one :response, :dependent => :destroy

accepts_nested_attributes_for :response

Response model

class Response < ActiveRecord::Base
belongs_to :question
end

_form.html.haml partial

    = simple_form_for @exam do |f|
      - if @exam.errors.any?
        #error_explanation
          %h2= "#{pluralize(@exam.errors.count, "error")} prohibited this exam from being saved:"
          %ul
            - @exam.errors.full_messages.each do |msg|
              %li= msg

      .field
        = f.label :Exam_Title
        = f.text_field :title , size: 100
      .field
        = f.label :date
        = f.datetime_select :date

      .field
        = f.simple_fields_for :questions do |question|
          = render "question_fields", f: question
        .links
          = link_to_add_association 'Add Question', f, :questions

      .field
        =f.label :unit
        =f.select :unit_id, Unit.all.map { |u| [u.name, u.id]}


      .actions
        = f.submit 'Save'

_questions.html.haml partial

    .nested-fields
    %br/
    = f.label :question, "Question"
    = link_to_remove_association "Remove Question", f
    %br/
    = f.cktext_area :question, :cols => 30, :ckeditor => {:uiColor => '#f7931e', :toolbar => 'mini'}
    %br/
    .link
        = link_to_add_association 'Add Answer', f, :response


    = f.fields_for :response do |answer|
        =render "response_fields", f: answer

_responses.html.haml partial

.nested-fields
%br/
= f.label :response, "Answer"
= link_to_remove_association "Remove Answer", f
= f.cktext_area :answer, :cols => 10, :ckeditor => {:uiColor => '#f7931e', :toolbar => 'mini'}

Update

exam edit page just renders the form. edit.html.haml

 %h1 Editing exam

= render 'form'

= link_to 'Show', @exam
\|
= link_to 'Back', exams_path

Parameters sent during save:

Parameters: {"utf8"=>"✓", "authenticity_token"=>"OvzRdRYT8zeCz6pTxcJT4o3maLb1TFw7iYxytZmnVkT7ZAG/maxeZLIoizlc8QMIMA4IrZoufh17Xkmt0NvG3A==", "exam"=>{"title"=>"Bla bla bla", "date(1i)"=>"2015", "date(2i)"=>"11", "date(3i)"=>"9", "date(4i)"=>"12", "date(5i)"=>"05", "questions_attributes"=>{"0"=>{"_destroy"=>"false", "question"=>"<table border=\"1\" cellpadding=\"1\" cellspacing=\"1\" style=\"width: 500px;\">\r\n\t<tbody>\r\n\t\t<tr>\r\n\t\t\t<td>blalal</td>\r\n\t\t\t<td>nalndjksl</td>\r\n\t\t</tr>\r\n\t\t<tr>\r\n\t\t\t<td>sdfjsdljfl</td>\r\n\t\t\t<td>kjfskldjfksl</td>\r\n\t\t</tr>\r\n\t\t<tr>\r\n\t\t\t<td>kdfjkdjf</td>\r\n\t\t\t<td>gldjkgldfj</td>\r\n\t\t</tr>\r\n\t</tbody>\r\n</table>\r\n\r\n<p>htkathiuerwehjr uyewuyrhjewhr ;aueryaueh rw erkjwherw</p>\r\n", "response_attributes"=>{"_destroy"=>"false", "answer"=>"<p><img alt=\"\" src=\"/uploads/ckeditor/pictures/1/content_hand_wrinting.gif\" style=\"width: 721px; height: 370px;\" /></p>\r\n"}, "id"=>"44"}}, "unit_id"=>"4"}, "commit"=>"Save", "id"=>"24"}

parameters sent during edit Parameters: {"id"=>"24"}

server log on loading the edit page

  Exam Load (0.9ms)  SELECT  "exams".* FROM "exams" WHERE "exams"."id" = $1 LIMIT 1  [["id", 24]]
  Question Load (0.5ms)  SELECT "questions".* FROM "questions" WHERE "questions"."exam_id" = $1  [["exam_id", 24]]
  Response Load (0.5ms)  SELECT  "responses".* FROM "responses" WHERE "responses"."question_id" = $1 LIMIT 1  [["question_id", 44]]
   (0.2ms)  BEGIN
  SQL (0.3ms)  DELETE FROM "responses" WHERE "responses"."id" = $1  [["id", 59]]
   (12.1ms)  COMMIT
  Rendered exams/_response_fields.html.haml (2.6ms)
  Rendered exams/_response_fields.html.haml (2.3ms)
  Rendered exams/_question_fields.html.haml (44.3ms)
  Rendered exams/_response_fields.html.haml (0.7ms)
  Rendered exams/_response_fields.html.haml (0.6ms)
  Rendered exams/_question_fields.html.haml (10.1ms)

Update! exam_controller.rb

def exam_params
  params.require(:exam).permit(:title, :attachment, :date, :unit_id, 
    questions_attributes:[ :id, :question, :exam_id,  :_destroy,
    response_attributes:[:id, :answer, :question_id, :_destroy]]
    # responses:[:id, :response, :question_id, :_destroy]]
    )
end

def new
@exam = Exam.new
  1.times do
    @exam.questions.build.build_response
  end

end

# GET /exams/1/edit def edit end

Thanks for for your help!

回答1:

Got it!!

The problem was here _questions.html.haml

.nested-fields
%br/
= f.label :question, "Question"
= link_to_remove_association "Remove Question", f
%br/
= f.cktext_area :question, :cols => 30, :ckeditor => {:uiColor => '#f7931e', :toolbar => 'mini'}
%br/
.link
    = link_to_add_association 'Add Answer', f, :response


= f.fields_for :response do |answer|
    =render "response_fields", f: answer

The line = link_to_add_association 'Add Answer', f, :response was causing the problem. it forces the previous answer to be removed so as to add a new one as opposed to editing the old one as expected.