ruby on rails - TypeError (Can't convert nil into String) With Attachment_Fu -


I am handling file attachments in my Rail app with attachment_foo, which is the public_filename method Returns the URL of a file that I am using on a model called Cover, so if I want to call the URL of an uploaded cover image, then I will do this: 

  & lt;% = image_tag (@cover .public_filename)%>

This works fine when the user has a proper attachment, but in my application it does not need to upload an attachment for a user. Therefore, a TypeError will be thrown by calling @ cover.public_filename : For obvious reasons, the zero in the string can not be changed that the file is zero.

However, I have trouble connecting the logic of this problem effectively because the object is zero, and with all the things like doing all the efforts @press.public_filename.nil? or if@cover .public_filename == Zero is meaningless and causes the same type of error.

What am I missing?

I have not worked with attachment_fu, but as I have seen public_filename is such a method that Depends on the field when you do not have attachments attached. I have read that attachment_fu should always be an attachment - and this is probably one of the reasons why you did not do this job. The authors also recommend using the plugin. Look at it!


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