rails 5 dropzone.js / carrierwaveを活用した直感的画像アップロードできない問題について

Question

#前提・実現したいこと
new画面で画像をアップロードした際に画像が保存され、
その後、editアクションをrenderし、画像をアップロードしたテーブルにtitile、book_discも保存できるようにする。

Rails 5.2.4.1
ruby 2.6.1p33
・Book テーブルカラム情報
title：string
book_disc：string
picture：string

#発生している問題・エラーメッセージ

・画像アップロード時

Started POST "/users/1/books" for ::1 at 2020-03-02 23:47:03 +0900
Processing by BooksController#create as JSON
Parameters: {"utf8"=>"✓", "authenticity_token"=>"puBrnLYgeeyU6tmtzB5mmkfevrCrwDBmQ5MGWr7JTYbMoBI0v2MqkxQS7XjWEkfE/5BWoTCDdTv67fVkLkb/5A==", "file"=>#, @original_filename="book_app_image3.png", @content_type="image/png", @headers="Content-Disposition: form-data; name=\"file\"; filename=\"book_app_image3.png\"\r\nContent-Type: image/png\r\n">, "user_id"=>"1"}
User Load (1.6ms) SELECT "users".* FROM "users" WHERE "users"."id" = ? ORDER BY "users"."id" ASC LIMIT ? [["id", 1], ["LIMIT", 1]]
↳ vendor/bundle/ruby/2.6.0/gems/activerecord-5.2.4.1/lib/active_record/log_subscriber.rb:98
Completed 500 Internal Server Error in 13ms (ActiveRecord: 1.6ms)

ArgumentError (':edit' is not an ActiveModel-compatible object. It must implement :to_partial_path.):

app/controllers/books_controller.rb:20:in `create'

・createボタン押下時

Started POST "/users/1/books" for ::1 at 2020-03-02 23:47:19 +0900
Processing by BooksController#create as HTML
Parameters: {"utf8"=>"✓", "authenticity_token"=>"puBrnLYgeeyU6tmtzB5mmkfevrCrwDBmQ5MGWr7JTYbMoBI0v2MqkxQS7XjWEkfE/5BWoTCDdTv67fVkLkb/5A==", "title"=>"rails ", "book_disc"=>"rails sample", "commit"=>"Create", "user_id"=>"1"}
User Load (0.4ms) SELECT "users".* FROM "users" WHERE "users"."id" = ? ORDER BY "users"."id" ASC LIMIT ? [["id", 1], ["LIMIT", 1]]
↳ vendor/bundle/ruby/2.6.0/gems/activerecord-5.2.4.1/lib/active_record/log_subscriber.rb:98
Completed 500 Internal Server Error in 6ms (ActiveRecord: 0.4ms)
ArgumentError (':edit' is not an ActiveModel-compatible object. It must implement :to_partial_path.):

app/controllers/books_controller.rb:20:in `create'

#該当のソースコード
view/books/new.html.erb

<h1>Record new</h1>

<!-- form_with url: user_books_path, local: true do |f| -->
<!-- end -->
<div class="book-new">
  <%= form_with url: user_books_path, local: true do |f| %>
    <div class="form-group" align="left">
      <%=f.label :title %><br>
      <%= f.text_field :title, value: "#{@book.title}", class: "form-control" %>
    </div>

    <div class="form-group" align="left">
      <%= f.label :book_disc %><br>
      <%= f.text_area :book_disc, value: "#{@book.book_disc}", class: "form-control" %>
    </div>

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

  <%= form_with url: user_books_path, class: 'dropzone', id: 'upload-dropzone', local: true do |f| %>
    <%= f.label :picture, class: "picture", align: "left" %>
      <div class="fallback">
      <%= f.file_field('attach[:file]') %>
      </div>
    <% end %>
  </div>

<div class="back-btn">
  <%= link_to "Back", user_books_path, class: "back-btn" %>
</div>

controllers/books_controller.rb

class BooksController < ApplicationController
  before_action :set_book, only: [:show, :edit, :update, :destroy]
  before_action :authenticate_user!
  before_action :ensure_correct_user, only: [:edit, :update, :destroy]

  def index
    @book = current_user.book.all
  end

  def all_user
    @book = Book.all
  end

  def new
    @book = Book.new
  end

  def create
    if @book = Book.new(picture: params[:file])
      render partial: :edit
    else
      @book = Book.new(title: params[:title],
                      book_disc: params[:book_disc],
                      user_id: current_user[:id],
                      picture: "default_book.jpg")
      end
    respond_to do |format|
      if @book.save
        format.html{redirect_to user_books_path, notice: 'Book was successfully created.'}
      else
        format.html{render :new}
      end
    end
  end

  def show
  end

  def edit
  end

  def update
    if @book.update(title: params[:title], book_disc: params[:book_disc])
      redirect_to user_books_path(current_user), notice: 'Book was successfully updated.'
    else
      render partial: :edit
    end
  end

  def destroy
    @book.destroy
    redirect_to user_books_path(current_user), notice: "Book was successfully deleted."
  end


  private

    def book_params
      params.require(:book).permit(:title, :book_disc, :user_id)
    end

    def set_book
      @book = Book.find_by(id: params[:id])
    end

    def ensure_correct_user
      if current_user.id != @book.user_id.to_i
        flash[:notice] = "You do not have permission"
        redirect_to user_books_path(current_user)
      end
    end

end

db/schema.rb 一部抜粋

ActiveRecord::Schema.define(version: 2020_02_23_133409) do

  create_table "books", force: :cascade do |t|
    t.string "title"
    t.string "book_disc"
    t.datetime "created_at", null: false
    t.datetime "updated_at", null: false
    t.integer "user_id"
    t.string "picture"
  end

#試したこと
下記サイトを参考に今回の実装作業をしました。
http://hinoshita.hatenadiary.com/entry/2016/10/11/223712

しかし、dropzoneは画像アップロード時にcreateが動作するため、title,book_discも併せて保存するため、createアクションはそれ用に修正しています。（しているつもりです、、）

もし、気になる点等ございましたら、コメントください。
また、情報不足ございましたら併せてコメントいただければ幸いです。
お手数ですがよろしくお願いいたします。