Paperclip is not supporting .doc file

问题

In rails 4.0.2, I am using paperclip gem to upload files. But it is not supporting .doc file. Below the file upload field, it is showing an error message as "has an extension that does not match its contents"

In model, the validation for checking the content type is given below :

validates_attachment_content_type :document, :content_type => ['application/txt', 'text/plain',
'application/pdf', 'application/msword',
'application/vnd.openxmlformats-officedocument.wordprocessingml.document',
'application/vnd.oasis.opendocument.text',
'application/x-vnd.oasis.opendocument.text',
'application/rtf', 'application/x-rtf', 'text/rtf', 
'text/richtext', 'application/doc', 'application/docx', 'application/x-soffice', 'application/octet-stream']

Gems which is used right now

rails (4.0.2, 4.0.0, 3.2.13, 3.2.8, 3.0.4, 3.0.3)

paperclip (3.5.2, 2.3.11, 2.3.8)

How can I solve this issue?

回答1:

add this to an initializer to disable spoofing protection:

require 'paperclip/media_type_spoof_detector'         
module Paperclip         
 class MediaTypeSpoofDetector        
    def spoofed?         
      false       
    end       
  end        
end             

For centOS

 module Paperclip     
 class MediaTypeSpoofDetector      
 def type_from_file_command      
  begin       
    Paperclip.run("file", "-b --mime :file", :file => @file.path)
  rescue Cocaine::CommandLineError
    ""
  end       
end      
end      
end

from https://github.com/thoughtbot/paperclip/issues/1429

回答2:

It's a bad idea to skip spoofing checking. Because Paperclip adds it for security reason. See this article for details: http://robots.thoughtbot.com/prevent-spoofing-with-paperclip

The spoof validation checks if file's extension matches it's mime type. For example a txt file's mime type is text/plain, when you upload it to Paperclip everything goes fine. But if you modify the extension to jpg then upload it, the validation fails because jpg file's mime type should be image/jpeg.

Note that this validation is for security checking so there's not a normal way to skip it. Even when you use do_not_validate_attachment_file_type it's not skipped. But for some files Paperclip can't recognize file -> mime type mapping correctly.

In this case the right way is adding content type mapping to Paperclip configuration. Like this:

# Add it to initializer
Paperclip.options[:content_type_mappings] = {
  pem: 'text/plain'
}

In this way it works without breaking spoofing validation. If you don't know what mime type a file is, you can use file command:

file -b --mime-type  some_file.pdf    # -> application/pdf

回答3:

The error in the server log means that your OS file command cannot get you the MIME type for a .doc file. This happens for me with ubuntu 12.04.

To get around this, I slightly altered MediaTypeSpoofDetector to use mimetype if file --mime didn't work.

module Paperclip
  class MediaTypeSpoofDetector
    private

    def type_from_file_command
      # -- original code removed --
      # begin
      #   Paperclip.run("file", "-b --mime-type :file", :file => @file.path)
      # rescue Cocaine::CommandLineError
      #   ""
      # end

      # -- new code follows --
      file_type = ''    

      begin
        file_type = Paperclip.run('file', '-b --mime-type :file', file: @file.path)
      rescue Cocaine::CommandLineError
        file_type = ''
      end

      if file_type == ''
        begin
          file_type = Paperclip.run('mimetype', '-b :file', file: @file.path)
        rescue Cocaine::CommandLineError
          file_type = ''
        end
      end

      file_type
    end
  end
end

回答4:

You can authorize all content types using do_not_validate_attachment_file_type :file

You can enable spoofing using has_attached_file :file,

class Upload
  #validate_media_type == false means "authorize spoofing"
  has_attached_file :file, validate_media_type: false

  #authorize all content types
  do_not_validate_attachment_file_type :file_if_content_type_missing
end

回答5:

Try putting do_not_validate_attachment_file_type :document validation in model.

来源：https://stackoverflow.com/questions/22527092/paperclip-is-not-supporting-doc-file