Rails PaperClip电子邮件附件不起作用

Question

I'm trying to email a PaperClip attachment. I've read several posts on StackExchange, but still can't get it to work. For some tries I get undefined method' , others take me to the login screen.

Comment Model:

  has_one :attachment

Mailer code I've tried:

attachments[comment.attachment.attach_file_name] = File.read(comment.attachment.to_file.path)

attachments[comment.attachment.attach_file_name] = File.read(comment.attachment.path)

attachments[comment.attachment.attach_file_name] = File.read(attachment_path(comment.attachment))

This is a copy of the browser console - I tried several things:

>> comment.attachment.attach_file_name
=> "2013-09-10_09-32-32.png"
>> comment.attachment.path
!! #<NoMethodError: undefined method `path' for #  <Attachment:0x007f8d06903450>>
>> attachment_path(comment.attachment)
=> "/attachments/75"
>> File.read(attachment_path(comment.attachment))
!! #<Errno::ENOENT: No such file or directory - /attachments/75>
>> File.read(attachment_path(comment.attachment).to_file)
!! #<NoMethodError: undefined method `to_file' for  "/attachments/75":String>
>> File.read(comment.attachment.path)
!! #<NoMethodError: undefined method `path' for # <Attachment:0x007f8d06903450>>
>> File.read(comment.attachment.to_file.path)
!! #<NoMethodError: undefined method `to_file' for # <Attachment:0x007f8d06903450>>
>>

So, this code:

attachment_path(comment.attachment)

Returns this:

"/attachments/75"

UDPATE

I tried this:

attachments[comment.attachment.attach_file_name] = File.read(comment.attachment.attach_url)

Got undefined method attach_url

So, tried these in the console:

>> comment.attachment.attach_url
!! #<NoMethodError: undefined method `attach_url' for # <Attachment:0x007f8d1c9b3cb8>>
>> attachment_path(comment.attachment)
=> "/attachments/76"
>> attachment_path(comment.attachment).attach_url
!! #<NoMethodError: undefined method `attach_url' for "/attachments/76":String>
>> attach_url(comment.attachment)
!! #<NoMethodError: undefined method `attach_url' for #<CommentMailer:0x007f8d145664d8>>
>> attach_url_path(comment.attachment)
!! #<NoMethodError: undefined method `attach_url_path' for # <CommentMailer:0x007f8d145664d8>>
>> attachment(comment.attachment)
!! #<NoMethodError: undefined method `attachment' for # <CommentMailer:0x007f8d145664d8>>
>>

Answer 1

This code sets up a one-to-one relationship between the Comment and the Attachment model:

has_one :attachment

This has nothing to do with Paperclip.

I assume that within your Attachment model you have something along the lines of the following:

has_attached_file :attach

You need to interact with the :attach attached to the Attachment model:

@comment.attachment.attach

When you're trying to attach this to your email you should be using something like this:

attachments[comment.attachment.attach_file_name] = File.read(comment.attachment.attach.path)