在活动管理员上使用paperclip更新图片

Question

我正在尝试使用有效的管理员上传图片。我没有错误但它什么也没做。这是一个例子：

当我点击创建时，我得到了这个：

模型 post.rb

class Post < ActiveRecord::Base
  has_attached_file :image, styles: { medium: "300x300>", thumb: "100x100>" }, default_url: "/images/:style/missing.png"
  validates_attachment_content_type :image, content_type: /\Aimage\/.*\Z/
    belongs_to :category
end

admin_post.rb

ActiveAdmin.register Post do
permit_params :title,:image

# CKEDITOR
form do |f|
  f.inputs do
    f.input :title
    f.input :image, :required => false, :as => :file
  end
  f.submit
end

index do
  column :title
  actions
end

show do |ad|
 attributes_table do
  row :title
  row :image do
   image_tag(ad.image.url(:thumb))
  end
  # Will display the image on show object page
 end
end 

end

迁移文件

class AddAttachmentImageToPosts < ActiveRecord::Migration
  def up
    add_attachment :posts, :image
  end

  def down
    remove_attachment :posts, :image
  end
end

我有一个posgres数据库，它只更新字段“Title”

添加图片时，这是日志文件：

Started POST "/admin/posts" for ::1 at 2016-04-15 10:10:10 +0200
  ActiveRecord::SchemaMigration Load (0.5ms)  SELECT "schema_migrations".* FROM "schema_migrations"
Processing by Admin::PostsController#create as HTML
  Parameters: {"utf8"=>"✓", "authenticity_token"=>"hJyaD6nfKLVKb1AXzTBQCe5cD6jpM6OBtr57MtssHtEILHclXt0lWka7RvSK6ttHRM7jnS04GTF2EdUnXNsa5A==", "post"=>{"title"=>"maquette", "image"=>#<ActionDispatch::Http::UploadedFile:0x84d0548 @tempfile=#<Tempfile:C:/Users/Bastou/AppData/Local/Temp/RackMultipart20160415-105332-926dwu.jpg>, @original_filename="maquette.jpg", @content_type="image/jpeg", @headers="Content-Disposition: form-data; name=\"post[image]\"; filename=\"maquette.jpg\"\r\nContent-Type: image/jpeg\r\n">}, "commit"=>"Create Post"}
  AdminUser Load (1.0ms)  SELECT  "admin_users".* FROM "admin_users" WHERE "admin_users"."id" = $1  ORDER BY "admin_users"."id" ASC LIMIT 1  [["id", 1]]
Unpermitted parameter: image
   (0.0ms)  BEGIN
  SQL (1.0ms)  INSERT INTO "posts" ("title", "created_at", "updated_at") VALUES ($1, $2, $3) RETURNING "id"  [["title", "maquette"], ["created_at", "2016-04-15 08:10:10.437177"], ["updated_at", "2016-04-15 08:10:10.437177"]]
   (2.5ms)  COMMIT
Redirected to http://localhost:3000/admin/posts/17
Completed 302 Found in 439ms (ActiveRecord: 10.0ms)


Started GET "/admin/posts/17" for ::1 at 2016-04-15 10:10:10 +0200
Processing by Admin::PostsController#show as HTML
  Parameters: {"id"=>"17"}
  AdminUser Load (0.0ms)  SELECT  "admin_users".* FROM "admin_users" WHERE "admin_users"."id" = $1  ORDER BY "admin_users"."id" ASC LIMIT 1  [["id", 1]]
  Post Load (0.5ms)  SELECT  "posts".* FROM "posts" WHERE "posts"."id" = $1 LIMIT 1  [["id", 17]]
  Rendered c:/RailsInstaller/Ruby2.2.0/lib/ruby/gems/2.2.0/bundler/gems/active_admin-d84f8190edac/app/views/active_admin/resource/show.html.arb (1316.0ms)
Completed 200 OK in 1433ms (Views: 1426.0ms | ActiveRecord: 0.5ms)


Started GET "/images/thumb/missing.png" for ::1 at 2016-04-15 10:10:12 +0200

ActionController::RoutingError (No route matches [GET] "/images/thumb/missing.png"):
  actionpack (4.2.5.1) lib/action_dispatch/middleware/debug_exceptions.rb:21:in `call'
  web-console (2.3.0) lib/web_console/middleware.rb:28:in `block in call'
  web-console (2.3.0) lib/web_console/middleware.rb:18:in `catch'
  web-console (2.3.0) lib/web_console/middleware.rb:18:in `call'
  actionpack (4.2.5.1) lib/action_dispatch/middleware/show_exceptions.rb:30:in `call'
  railties (4.2.5.1) lib/rails/rack/logger.rb:38:in `call_app'
  railties (4.2.5.1) lib/rails/rack/logger.rb:20:in `block in call'
  activesupport (4.2.5.1) lib/active_support/tagged_logging.rb:68:in `block in tagged'
  activesupport (4.2.5.1) lib/active_support/tagged_logging.rb:26:in `tagged'
  activesupport (4.2.5.1) lib/active_support/tagged_logging.rb:68:in `tagged'
  railties (4.2.5.1) lib/rails/rack/logger.rb:20:in `call'
  actionpack (4.2.5.1) lib/action_dispatch/middleware/request_id.rb:21:in `call'
  rack (1.6.4) lib/rack/methodoverride.rb:22:in `call'
  rack (1.6.4) lib/rack/runtime.rb:18:in `call'
  activesupport (4.2.5.1) lib/active_support/cache/strategy/local_cache_middleware.rb:28:in `call'
  rack (1.6.4) lib/rack/lock.rb:17:in `call'
  actionpack (4.2.5.1) lib/action_dispatch/middleware/static.rb:116:in `call'
  rack (1.6.4) lib/rack/sendfile.rb:113:in `call'
  railties (4.2.5.1) lib/rails/engine.rb:518:in `call'
  railties (4.2.5.1) lib/rails/application.rb:165:in `call'
  rack (1.6.4) lib/rack/lock.rb:17:in `call'
  rack (1.6.4) lib/rack/content_length.rb:15:in `call'
  rack (1.6.4) lib/rack/handler/webrick.rb:88:in `service'
  c:/RailsInstaller/Ruby2.2.0/lib/ruby/2.2.0/webrick/httpserver.rb:138:in `service'
  c:/RailsInstaller/Ruby2.2.0/lib/ruby/2.2.0/webrick/httpserver.rb:94:in `run'
  c:/RailsInstaller/Ruby2.2.0/lib/ruby/2.2.0/webrick/server.rb:294:in `block in start_thread'


  Rendered c:/RailsInstaller/Ruby2.2.0/lib/ruby/gems/2.2.0/gems/actionpack-4.2.5.1/lib/action_dispatch/middleware/templates/rescues/_trace.html.erb (2.0ms)
  Rendered c:/RailsInstaller/Ruby2.2.0/lib/ruby/gems/2.2.0/gems/actionpack-4.2.5.1/lib/action_dispatch/middleware/templates/routes/_route.html.erb (3.0ms)
  Rendered c:/RailsInstaller/Ruby2.2.0/lib/ruby/gems/2.2.0/gems/actionpack-4.2.5.1/lib/action_dispatch/middleware/templates/routes/_table.html.erb (8.0ms)
  Rendered c:/RailsInstaller/Ruby2.2.0/lib/ruby/gems/2.2.0/gems/actionpack-4.2.5.1/lib/action_dispatch/middleware/templates/rescues/_request_and_response.html.erb (1.0ms)
  Rendered c:/RailsInstaller/Ruby2.2.0/lib/ruby/gems/2.2.0/gems/actionpack-4.2.5.1/lib/action_dispatch/middleware/templates/rescues/routing_error.html.erb within rescues/layout (885.9ms)
  Rendered c:/RailsInstaller/Ruby2.2.0/lib/ruby/gems/2.2.0/gems/web-console-2.3.0/lib/web_console/templates/_markup.html.erb (0.5ms)
  Rendered c:/RailsInstaller/Ruby2.2.0/lib/ruby/gems/2.2.0/gems/web-console-2.3.0/lib/web_console/templates/_inner_console_markup.html.erb within layouts/inlined_string (0.5ms)
  Rendered c:/RailsInstaller/Ruby2.2.0/lib/ruby/gems/2.2.0/gems/web-console-2.3.0/lib/web_console/templates/_prompt_box_markup.html.erb within layouts/inlined_string (0.5ms)
  Rendered c:/RailsInstaller/Ruby2.2.0/lib/ruby/gems/2.2.0/gems/web-console-2.3.0/lib/web_console/templates/style.css.erb within layouts/inlined_string (0.5ms)
  Rendered c:/RailsInstaller/Ruby2.2.0/lib/ruby/gems/2.2.0/gems/web-console-2.3.0/lib/web_console/templates/console.js.erb within layouts/javascript (555.0ms)
  Rendered c:/RailsInstaller/Ruby2.2.0/lib/ruby/gems/2.2.0/gems/web-console-2.3.0/lib/web_console/templates/main.js.erb within layouts/javascript (0.0ms)
  Rendered c:/RailsInstaller/Ruby2.2.0/lib/ruby/gems/2.2.0/gems/web-console-2.3.0/lib/web_console/templates/error_page.js.erb within layouts/javascript (0.5ms)
  Rendered c:/RailsInstaller/Ruby2.2.0/lib/ruby/gems/2.2.0/gems/web-console-2.3.0/lib/web_console/templates/index.html.erb (1282.9ms)