Cleaning up Paperclip error messages

Question

Okay, so i've got paperclip working, and I'm trying to use the built in validator to make sure that the file uploaded

1. Is an image
2. Is not too big

So I have this in the model, per the documentation:

validates_attachment :avatar,
:content_type => { :content_type => /image/ },
:size => { :in => 0..2.megabytes }

However the error it shows in the view is this mess:

I'd like it to be something a bit simpler, like "Avatar must be an image less than 2 megabytes"

However, I can't see where to do this, as passing :message => 'something' throws an error Unknown validator: 'MessageValidator'

How do I go about cleaning this up?

Note that the happy path of uploading a small image works just fine.

Some further testing shows that uploading an image that's too big (like a desktop background) or something that's not a .rb file fails more gracefully, but doesn't display any error message at all. Still not quite what I want.

Answer 1

Obviously you solved this for yourself a long time ago, but for anyone who is looking for the answer, there is actually a way to do it within the provided validation.

Simple add your message like so:

validates_attachment :avatar,
:content_type => { :content_type => /image/, :message => "Avatar must be an image" },
:size => { :in => 0..2.megabytes, :message => "Avatar must be less than 2 megabytes in size" }

Answer 2

I ended up writing two custom validators. It's true that these do the same thing the paperclip validators do, but they fail prettier:

  def avatar_is_a_image
    if self.avatar?
      if !self.avatar.content_type.match(/image/)
        errors.add(:avatar, "Avatar must be an image")
      end
    end
  end

  def avatar_is_less_than_two_megabytes
    if self.avatar?
      if self.avatar.size > 5.megabytes
        errors.add(:avatar, "Avatar must be less than 5 megabytes in size")
      end
    end
  end