Purl issues

Query parameters
Suppose you do a partial redirect There is no way to add another query parameter. and Solution: If the redirected to partial URI has a query parameter, then convert the first "?" in the redirected portion to an "&". Then you would have
 * purl.org/NET/foo/ => foo.com/process?ref=
 * purl.org/NET/foo/?bar=10 leads to:
 * foo.com/process?ref=purl.org/NET/foo/?bar=10 instead of
 * foo.com/process?ref=purl.org/NET/foo/&bar=10
 * purl.org/NET/foo/&bar=10 isn't correct.
 * purl.org/NET/foo/?bar=10 => foo.com/process?ref=purl.org/NET/foo/&bar=10

Partial redirects not ending in /
For OBI we need URIs of the form http://purl.obofoundry.org/obo/OBI_0000225

Currently we need to create each one as a separate purl. We would like, instead, to have a partial redirect from http://purl.obofoundry.org/obo/OBI_

Permanency
PURLs can't be deleted. While this makes sense for PURLs that are intended to be long lived, sometimes we make a mistake and want to delete them. For example, a spelling mistake was made: wrong / right

Perhaps PURLs should have a provision to mark permanency. For example, see http://www.nlm.nih.gov/permlevels.html

Dump of rewrite rules
The tool we wrote is inefficient (scrapes html results of http://purl.org/maint/display.html)

Misc

 * Specify the redirect code (301, 302, 303 etc)
 * Link header. Cache some RDF metadata at server