Passing Tempfile from Rack to Exif::Data.new raises an error

[Aupajo]

If I have an upload coming from Rack:

> file
#<Tempfile:/var/folders/r4/rd0m9j997h19dm1nz9_fg2540000gn/T/RackMultipart20171019-54278-1v4nvvt.jpg>

If I try to parse it with Exif::Data.new, I get the following error:

> Exif::Data.new(file)
TypeError: wrong argument type Tempfile (expected String or IO)

[tonytonyjan]

This is expected behavior since Tempfile is not an IO but a DelegateClass(File). A workaround would be calling Tempfile#read before passing it to Exif::Data.new.

In fact, I am thinking about to add a feature to support objects with some interfaces like #read being implemented and thus some built-in class like StringIO and Tempfile can work.

[tonytonyjan]

exif v2.1.0 has been released and it should solve this issue. Thanks for making exif better :)

[Aupajo]

@tonytonyjan Thank you for the quick fix 😄