Jwt.key: def of bend-kit-jwt@0.11.0.1
Import: import bend-kit-jwt@0.11.0.1/jwt.bend as Jwt
Lines 870-878 of bend-kit-jwt@0.11.0.1/jwt.bend: https://jend.leeeet.dev/read.txt?path=bend-kit-jwt@0.11.0.1/jwt.bend&start_line=870&end_line=878

import Base
import bend-kit-hairpin@0.13.0.1/hairpin.bend as Hairpin

# The verify key named kid for alg a. A known key stays usable through the 60 s fetch cooldown even
# when ttl is shorter. After that, refresh a stale set or an unknown kid at most once a minute.
# ponytail: fixed 60 s cooldown; make it a Jwks field if an issuer rotates faster.
def key(c: Hairpin.Client, s: Jwks, +kid: String, +a: Alg, +now: U32) -> IO(Hairpin.Client & Jwks & Result<&1, &1, Err, Key>):
  Jwks{+url, +ttl, +live, +at, +tried, +ks} = s
  +found = jwk.pick(ks, kid, a)
  +fresh = Bool.and(live, Bool.and(U32.is_le(at, now), U32.is_lt((now - at : U32), Bool.pick(U32, U32.is_lt(ttl, 60), 60, ttl))))
  +cached = Bool.and(fresh, Maybe.is_some(&2, Jwk, found))
  key.go(cached, U32.is_le(60, since(now, tried)), c, Jwks{url, ttl, live, at, tried, ks}, found, kid, a, now)

Uses (20):
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=Bool.and
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=Bool.pick
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=IO
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=Maybe.is_some
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=Pair
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=Result
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=String
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=U32
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=U32.is_le
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=U32.is_lt
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=U32.sub
  https://jend.leeeet.dev/definition.txt?path=bend-kit-hairpin@0.13.0.1/hairpin.bend&name=Client
  https://jend.leeeet.dev/definition.txt?path=bend-kit-jwt@0.11.0.1/jwt.bend&name=Alg
  https://jend.leeeet.dev/definition.txt?path=bend-kit-jwt@0.11.0.1/jwt.bend&name=Err
  https://jend.leeeet.dev/definition.txt?path=bend-kit-jwt@0.11.0.1/jwt.bend&name=Jwk
  https://jend.leeeet.dev/definition.txt?path=bend-kit-jwt@0.11.0.1/jwt.bend&name=Jwks
  https://jend.leeeet.dev/definition.txt?path=bend-kit-jwt@0.11.0.1/jwt.bend&name=Key
  https://jend.leeeet.dev/definition.txt?path=bend-kit-jwt@0.11.0.1/jwt.bend&name=jwk.pick
  https://jend.leeeet.dev/definition.txt?path=bend-kit-jwt@0.11.0.1/jwt.bend&name=key.go
  https://jend.leeeet.dev/definition.txt?path=bend-kit-jwt@0.11.0.1/jwt.bend&name=since