Colorbox

I’ve been modifying the Repository code to allow for additional storage backends for the surrogates created from the assets attached to Digital Objects. Currently we use an S3 compatible backend, but would like the option of simple file storage. Part of this requires serving the surrogate files from the application rather than re-directing to the S3 URLs.

Serving the files is reasonably straightforward with Rails. Once the path, or URL for the file is retrieved from the storage backend it can be returned using the send data method. Including the type in the response is important if you want the file to display inline.

open(file) do |f|
 send_data f.read, 
 type: MIME::Types.type_for(file_name).first.content_type, 
 disposition: 'inline'
end

A harder to figure out problem was with the lightbox that we use to display a larger version of the surrogate. Opening the new surrogate URL in a browser displayed the surrogate inline correctly, however, within the lightbox the image would display as text. Eventually I found this option in the colorbox documentation:

The new URLs did not end in the surrogate filename, so automatic detection was not working. By adding the photo option to the colorbox initializer the image finally displayed correctly.

colorbox({rel:"group1", maxWidth:"95%", maxHeight:"95%", photo: true});