Haunted by Headers

Had an interesting problem today tracing the origin of some HTTP headers. An application which uses mod_plsql (non-APEX) was constantly returning some troublesome header information which we needed to remove, particularly when a certain procedure was called. I searched every where in the OAS interface, but none of the settings seemed to be applicable. Eventually I found the culprit was an apache declaration in dads.conf. Why it was there I can only speculate, not having built the application.

On the up side, I can now clarify some more of the behaviour of the undocumented htp.init procedure. During the process of tracing the problem, I attempted to use htp.init to suppress the headers from showing up when calling a particular procedure. Apparently this isn't how it works. The application server still amends header information to the response before it is sent.