Rails - 回形针不上传照片？显示缺失.png

Question

我安装了 Paperclip gem，用它在我的模型中生成 :image 列。然后编辑视图让我上传照片：

<%= form_for @book = Book.new, :html => { :multipart => true } do |f| %>
...
...
...

<%= f.file_field :image %>

在我的模型中，我输入了这一行：

has_attached_file :image, :styles => { :smal => "200x200>"}
                  :url  => "/assets/books/:id/:style/:basename.:extension",
                  :path => ":rails_root/public/assets/books/:id/:style/:basename.:extension"

我可以选择上传照片，当我上传它时，它会报错为missing.png，即使图像名称不是这样，似乎根本没有上传照片。有什么问题？ 编辑：完全错误：

    No route matches [GET] "/assets/books/17/small/thunderbird-logo-200x200.png"

 actionpack (4.0.0) lib/action_dispatch/middleware/debug_exceptions.rb:21:in `call'
  actionpack (4.0.0) lib/action_dispatch/middleware/show_exceptions.rb:30:in `call'
  railties (4.0.0) lib/rails/rack/logger.rb:38:in `call_app'
  railties (4.0.0) lib/rails/rack/logger.rb:21:in `block in call'
  activesupport (4.0.0) lib/active_support/tagged_logging.rb:67:in `block in tagged'
  activesupport (4.0.0) lib/active_support/tagged_logging.rb:25:in `tagged'
  activesupport (4.0.0) lib/active_support/tagged_logging.rb:67:in `tagged'
  railties (4.0.0) lib/rails/rack/logger.rb:21:in `call'
  actionpack (4.0.0) lib/action_dispatch/middleware/request_id.rb:21:in `call'
  rack (1.5.2) lib/rack/methodoverride.rb:21:in `call'
  rack (1.5.2) lib/rack/runtime.rb:17:in `call'
  activesupport (4.0.0) lib/active_support/cache/strategy/local_cache.rb:83:in `call'
  rack (1.5.2) lib/rack/lock.rb:17:in `call'
  actionpack (4.0.0) lib/action_dispatch/middleware/static.rb:64:in `call'
  railties (4.0.0) lib/rails/engine.rb:511:in `call'
  railties (4.0.0) lib/rails/application.rb:97:in `call'
  rack (1.5.2) lib/rack/lock.rb:17:in `call'
  rack (1.5.2) lib/rack/content_length.rb:14:in `call'
  rack (1.5.2) lib/rack/handler/webrick.rb:60:in `service'
  /usr/local/lib/ruby/2.0.0/webrick/httpserver.rb:138:in `service'
  /usr/local/lib/ruby/2.0.0/webrick/httpserver.rb:94:in `run'
  /usr/local/lib/ruby/2.0.0/webrick/server.rb:295:in `block in start_thread'


  Rendered /usr/local/lib/ruby/gems/2.0.0/gems/actionpack-4.0.0/lib/action_dispatch/middleware/templates/rescues/_trace.erb (5.9ms)
  Rendered /usr/local/lib/ruby/gems/2.0.0/gems/actionpack-4.0.0/lib/action_dispatch/middleware/templates/routes/_route.html.erb (2.5ms)
  Rendered /usr/local/lib/ruby/gems/2.0.0/gems/actionpack-4.0.0/lib/action_dispatch/middleware/templates/routes/_table.html.erb (1.3ms)
  Rendered /usr/local/lib/ruby/gems/2.0.0/gems/actionpack-4.0.0/lib/action_dispatch/middleware/templates/rescues/routing_error.erb within rescues/layout (27.2ms)

Answer 1

您可以通过添加控制器私有 service_params 来修复此错误

控制器：

  private
# Use callbacks to share common setup or constraints between actions.
def set_service
  @service = Service.find(params[:id])
end

# Never trust parameters from the scary internet, only allow the white list through.
def service_params
  params.require(:service).permit(:title, :about, :price, :photo)
end

您必须将 :photo 添加到 :title、:about、:price （或您所拥有的东西）

Answer 2

尝试显式设置路径和url

    has_attached_file :image,
      :path => ":rails_root/public/system/:attachment/:id/:style/:filename",
      :url => "/system/:attachment/:id/:style/:filename", 
      :styles => { :smal => "200x200>" }