I have been struggling a lot with issues concerning remote image paths that does not have a regular image extension, and hence cannot be processed by carrierwave. This is often the case with remote images on image servers etc. E. g. "https://encrypted-tbn0.gstatic.com/images?q=tbn:ANd9GcSbK2NSUILnFozlX-oCWQ0r2PS2gHPPF7c8XaxGuJFGe83KGJkhFtlLXU_u" The file does not have a .jpeg extension, but the content_type is always correct in those examples. In this case Kernel.open would return "content-type"=>"image/jpeg".
The other day I stumbled upon this solution http://stackoverflow.com/a/19384117/1002814 and I'm wondering why this is not the default actually?
Until yesterday this would've required adding a mime-types dependency. But now, as we already have one, I don't see any reason an approach like this shouldn't be the default.
Closing in favor of #1248