Allow use of URL-namespaced claims

[willthames]

Private namespaced claims are recommended to be prefixed with URLs, but having dots in domain names means that working out nested key structure by splitting on dots doesn't work.

Instead we assume that if a claim starts with http:// or https:// then everything up to the third slash is part of the top-level key

So https://example.com/nested.claims.key gets treated as https://example.com/nested -> claims -> key

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[willthames]

I'll mark this as draft while I work on getting the CLA sorted.

[nareddyt]

/ok-to-test

[willthames]

Private namespaced claims are recommended to be prefixed with URLs

Can you link to a specification that mentions this?

https://auth0.com/docs/secure/tokens/json-web-tokens/create-custom-claims#namespaced-guidelines

See also https://github.com/quarkusio/quarkus/issues/26185 for a similar issue in another library

It might only be auth0 who recommend this, but auth0 are a major advocate of JWT (they seem to be behind jwt.io for example)

[jgorinsky]

I ran into this issue while trying to extract namespaced JWT claims into headers with envoy.

The JWT RFC (https://datatracker.ietf.org/doc/html/rfc7519#section-4.2) mentions using a domain name as a "Collision-Resistant Name" for claims and includes an example elsewhere using a domain namespaced claim:

{
  "iss":"joe",
  "exp":1300819380,
  "http://example.com/is_root":true
}