[LON-CAPA-admin] Unicode BOM problem in resource filenames

[Craig Wiegert]

Hi all,

One of our instructors has encountered difficulties with some of the
problems in the OpenStax archive.  He is able to incorporate the
resources into a sequence just fine, and both he and the students can
access the problems.  However, whenever someone submits an answer, they
get the "invalid access" error: "Sorry... This action is currently not
authorized."

For example, in the

  /res/fsu/openstax-CollegePhysics/14_HeatAndHeatTransfer/

directory, he was having trouble with Problems 05, 08, and 10.

It turns out that the filename for each of these troublesome problems
includes a UTF-8 encoded "invisible" Byte-Order Mark (BOM) right after
the underscore (hex ef bb bf).  This is evident by looking at the
URL-encoding of these resource filenames, e.g., when incorporating them
into a sequence.

Is our ability to "read but not answer" these problems a Unicode bug
within the perl code of LON-CAPA itself?  Is it something obscurely
locale-related on our servers?  Any help would be appreciated!

  - Craig

----------------------------------------------------------------------
Craig Wiegert                           Office: 215 Physics Building
Undergraduate Physics Coordinator
Associate Professor                     Phone: 706-542-4023
Department of Physics & Astronomy       Fax: 706-542-2492
University of Georgia                   Email: wiegert at physast.uga.edu
Athens, GA  30602-2451                         cwiegert at uga.edu