编辑具有以前成功上传的图像的记录时,如何在编辑时不必重新上传？

Question

我正在使用Carrierwave,Fog将图像上传到S3.

问题是,当我去编辑记录时,"文件"和"照片"字段会自动变为空白.因此,如果我想保留记录中的图像或文件,我必须重新上传它.

否则,会发生什么是上传的文件/图像消失了.我甚至不确定它是否从S3中删除,但与我在db中的记录的关联消失了.

这是_form.html.erb我的Post模型的SimpleForm 部分:

<%= simple_form_for(@post, html: {class: 'form-horizontal' }) do |f| %> 
    <%= f.error_notification %>
    <%= f.input_field :title, placeholder: "Enter Title"  %>
    <%= f.input_field :body, id: "body-field", placeholder: "Provide all the facts." %>
    <%= f.input_field :photo %>
    <%= f.input_field :file %>
    <%= f.button :submit, class: "btn btn-primary pull-left" %>
<% end %>

这是我的 PhotoUploader

class PhotoUploader < CarrierWave::Uploader::Base
  include CarrierWave::RMagick
  storage :fog

  include CarrierWave::MimeTypes
  process :set_content_type

  def store_dir
    "images/#{model.class.to_s.underscore}/#{mounted_as}/#{model.id}"
  end

    version :main_thumb_mobile do
      process :resize_to_fit => [52, 52]
    end

    version :main_thumb do
      process :resize_to_fit => [150, 150]
    end

    version :post_thumb do
      process :resize_to_fit => [200, 200]
    end

    version :large do
      process :resize_to_limit => [400, 400]
    end

  def extension_white_list
    %w(jpg jpeg gif png)
  end
end

这是我的 FileUploader

class FileUploader < CarrierWave::Uploader::Base
  storage :fog
  def store_dir
    "files/#{model.class.to_s.underscore}/#{mounted_as}/#{model.id}"
  end

  def extension_white_list
    %w(pdf doc docx xls xlsx ppt pptx txt mp4 m4v mov avi mkv mp3 wav)
  end    
end

这是我的架构Post:

# == Schema Information
# truncated for brevity
# Table name: posts
#
#  id                    :integer          not null, primary key
#  title                 :text
#  photo                 :string(255)
#  body                  :text
#  user_id               :integer
#  file                  :string(255)

编辑1

这是我的Post.rb:

# == Schema Information
#
# Table name: posts
#
#  id                    :integer          not null, primary key
#  title                 :text
#  photo                 :string(255)
#  body                  :text
#  created_at            :datetime
#  updated_at            :datetime
#  user_id               :integer
#  ancestry              :string(255)
#  file                  :string(255)
#  status                :integer          default(0)
#  slug                  :string(255)
#  publication_status    :integer          default(0)
#  has_eyewitness        :boolean          default(FALSE)
#  youtube_embed_code    :text
#  soundcloud_embed_code :text
#

class Post < ActiveRecord::Base
  has_ancestry
  belongs_to :user
  resourcify
  enum status: [ :unconfirmed, :corroborated, :confirmed ]
  enum publication_status: [ :unpublished, :published ]
  extend FriendlyId
  friendly_id :title, use: [:slugged, :history, :finders]

  attr_accessor :country

  mount_uploader :photo, PhotoUploader
  mount_uploader :file, FileUploader

  validates_presence_of :body
  validates_length_of :body, maximum: 150, too_long: 'The report must be less than 150 words.',
                        tokenizer: ->(str) { str.scan(/\w+/) }
  validates_length_of :title, maximum: 7, too_long: 'The title must be less than 7 words.',
                                              tokenizer: ->(str) { str.scan(/\w+/) }

  def publish
    published!
  end

  def unpublish
    unpublished!
  end

  def is_published?
    if self.published?
      "yes"
    else
      "no"
    end
  end      
end

编辑2

我根据jaspreet的建议更改了f.input_field :photo我的表单f.file_field :photo,但仍然无法正常工作.这是我更新请求的日志:

Started PATCH "/posts/ognr-takes-over-amcham-6a6f01ba-a9f9-44d5-924a-72f666f20ca8" for 127.0.0.1 at 2014-12-28 13:51:38 -0500
Processing by PostsController#update as HTML
  Parameters: {"utf8"=>"?", "authenticity_token"=>"S7FOq956fox6XYpar7Yd6V7AL+bwypQQxZktjHW3PNc=", "post"=>{"parent_id"=>"", "status"=>"unconfirmed", "publication_status"=>"unpublished", "title"=>"OGNR takes over AMCHAM", "body"=>"OGNR storms the rerl.", "has_eyewitness"=>"1", "youtube_embed_code"=>"", "soundcloud_embed_code"=>""}, "commit"=>"Update Post", "id"=>"ognr-takes-over-amcham-6a6f01ba-a9f9-44d5-924a-72f666f20ca8"}
  User Load (1.7ms)  SELECT  "users".* FROM "users"  WHERE "users"."id" = 1  ORDER BY "users"."id" ASC LIMIT 1
   (1.2ms)  SELECT COUNT(*) FROM "roles" INNER JOIN "users_roles" ON "roles"."id" = "users_roles"."role_id" WHERE "users_roles"."user_id" = $1 AND (((roles.name = 'admin') AND (roles.resource_type IS NULL) AND (roles.resource_id IS NULL)))  [["user_id", 1]]
   (6.4ms)  SELECT COUNT(*) FROM "roles" INNER JOIN "users_roles" ON "roles"."id" = "users_roles"."role_id" WHERE "users_roles"."user_id" = $1 AND (((roles.name = 'editor') AND (roles.resource_type IS NULL) AND (roles.resource_id IS NULL)))  [["user_id", 1]]
   (0.2ms)  BEGIN
  Post Exists (1.0ms)  SELECT  1 AS one FROM "posts" INNER JOIN "friendly_id_slugs" ON "friendly_id_slugs"."sluggable_id" = "posts"."id" AND "friendly_id_slugs"."sluggable_type" = 'Post' WHERE ("posts"."id" IS NOT NULL) AND "posts"."slug" = 'ognr-takes-over-amcham' LIMIT 1
  SQL (0.6ms)  INSERT INTO "posts" ("body", "created_at", "has_eyewitness", "slug", "soundcloud_embed_code", "title", "updated_at", "youtube_embed_code") VALUES ($1, $2, $3, $4, $5, $6, $7, $8) RETURNING "id"  [["body", "OGNR storms the rerl."], ["created_at", "2014-12-28 18:51:39.183091"], ["has_eyewitness", "t"], ["slug", "ognr-takes-over-amcham-cd491a8e-9a4e-4d5e-b13a-898de4adf135"], ["soundcloud_embed_code", ""], ["title", "OGNR takes over AMCHAM"], ["updated_at", "2014-12-28 18:51:39.183091"], ["youtube_embed_code", ""]]
  FriendlyId::Slug Load (0.5ms)  SELECT  "friendly_id_slugs".* FROM "friendly_id_slugs"  WHERE "friendly_id_slugs"."sluggable_id" = $1 AND "friendly_id_slugs"."sluggable_type" = $2  ORDER BY "friendly_id_slugs".id DESC LIMIT 1  [["sluggable_id", 43], ["sluggable_type", "Post"]]
  SQL (0.4ms)  DELETE FROM "friendly_id_slugs" WHERE "friendly_id_slugs"."sluggable_id" = $1 AND "friendly_id_slugs"."sluggable_type" = $2 AND "friendly_id_slugs"."slug" = 'ognr-takes-over-amcham-cd491a8e-9a4e-4d5e-b13a-898de4adf135'  [["sluggable_id", 43], ["sluggable_type", "Post"]]
  SQL (0.4ms)  INSERT INTO "friendly_id_slugs" ("created_at", "slug", "sluggable_id", "sluggable_type") VALUES ($1, $2, $3, $4) RETURNING "id"  [["created_at", "2014-12-28 18:51:39.242475"], ["slug", "ognr-takes-over-amcham-cd491a8e-9a4e-4d5e-b13a-898de4adf135"], ["sluggable_id", 43], ["sluggable_type", "Post"]]
   (2.6ms)  COMMIT
Redirected to http://localhost:3000/posts/ognr-takes-over-amcham-cd491a8e-9a4e-4d5e-b13a-898de4adf135
Completed 302 Found in 372ms (ActiveRecord: 17.3ms)

编辑3

该PostController#Update如下所示:

class PostsController < ApplicationController
  load_and_authorize_resource

  def update
    respond_to do |format|
      if @post.update(post_params)
        format.html { redirect_to @post, notice: 'Report was successfully updated.' }
        format.json { render :show, status: :ok, location: @post }
      else
        format.html { render :edit }
        format.json { render json: @post.errors, status: :unprocessable_entity }
      end
    end
  end

编辑4

Answer 1

我发现的最简单的解决方案是简单地添加一个检查以查看是否附加了照片，例如if @post.photo?，然后仅显示标签（如果是这样的话）。

当然，这是假设我不想改变图像。

<% if @post.photo? %>
    <label><%= @post.photo.file.filename %></label>
<% else %>
    <label for="photoFileUpload">Upload Images:</label>
    <%= f.input_field :photo %>
    <p class="help-block">Allowed: png, gif, jpg/jpeg</p>
<% end %>