Identifier “foo” is not in canonical form (tha canonical form would be “bar”)


URIs used as identifiers should be in canonical form, as described by section 6 of RFC 3986. This means that insignificant differences (e.g., case of hostname) are removed, so URIs can be compared character-by-character to determine equivalence. This is particularly important when content is syndicated, and the same entry may appear in multiple feeds.

Also avoid leading and trailing whitespace as clients vary in their interpretation of such characters.


All newly issued ids should be in canonical form. Use the canonical form given in the warning message for guidance.


Not clear? Disagree?

You might be able to find help in one of these fine resources.

Copyright © 2002-4 Mark Pilgrim and Sam Ruby