A warning or archive identifier (after normalizeIdentifier) is a single path
segment: a non-blank string without a path separator (/ or \), whitespace, control
or invisible format characters. A blank one would address a different path
(/warnings/.json, /archive.mowas/-mapping.json); one with a separator is
percent-encoded and can never match a real id (a ../../etc/passwd attempt included);
and no real id contains whitespace or an invisible character, which the API answers with
a redirect to its archive. All are refused before any request rather than ending in a
remote 404 or a "not a live warning" that reads like an expired id.
A warning or archive identifier (after normalizeIdentifier) is a single path segment: a non-blank string without a path separator (
/or\), whitespace, control or invisible format characters. A blank one would address a different path (/warnings/.json,/archive.mowas/-mapping.json); one with a separator is percent-encoded and can never match a real id (a../../etc/passwdattempt included); and no real id contains whitespace or an invisible character, which the API answers with a redirect to its archive. All are refused before any request rather than ending in a remote 404 or a "not a live warning" that reads like an expired id.