Jwt

A signed token (RFC 7519) in JWS compact form, three parts of unpadded Base64url joined by ., at most 8,192 characters; an unsecured token, with no signature, is never one. crypto.verify_jwt checks it. A secret value (chunk 5.5r2): never sent, logged, stored or shown, and compared in constant time.

Security; not ordered; since Jadpo 0.1.0.

Make one

It comes from outside your code, a secret value that never appears in it.

text.parse(raw, as: Jwt) reads one from its text; text that isn't one at all fails malformed, such as "".

Text, JSON and storage

text.parse reads one from its text, as it is typed. Nothing writes it: text.from and text.format don't take it, JSON writes it as "<redacted Jwt>", and it is never stored.

Shown to people

text.format doesn't take it: a Jwt is never shown.

Operations

• crypto.verify_jwt(token: Jwt, keys: List<Jwk>, issuer: Text?, audience: Text?, as: Type?) -> JwtClaims: The registered claims of token once it holds: signed by one of keys with that key's own algorithm (Ed25519, RS256 for an RSA key, ES256 for a P-256 key), never the one the token names, so none and every other algorithm fail invalid_signature; not expired, not used before its nbf and not issued later than now, against the clock with 30 seconds' leeway (expired, not_yet_valid); issued by issuer when one is given (wrong_issuer); and for audience, or for no audience when none is given (wrong_audience). A token that isn't one, or has no exp, is malformed. With as:, an object type of the application's, it gives instead the token's claims the type names, read as json.read reads it, a registered one as JwtClaims holds it, and fails mismatch when they aren't the type. It reads the clock, so it is called only in actions.

Like every standard type, it also has the contract's own operations: text.parse, json.read, json.write and ==. It isn't ordered, so < and sorting don't take it. Every standard type meets one contract says how they work.