The Altcha authorization check, plugged into the
ICommandAuthorizationCheck / IQueryAuthorizationCheck seam.
Behavior
- Self-applies: returns Allowed for any request whose type isn't
decorated with [Altcha]. No-op for the 99% of endpoints that don't
need PoW.
- Reads ctx.Items["mobile_attested"] for Phase 3 bypass when the
attribute's AllowMobileAttestationBypass is true.
- Pulls the solution off the request via IHasAltchaSolution and
delegates verification to IAltchaVerifier (resolved per-call from
the request scope, so any verifier lifetime works).
- Stashes a diagnostic reason in ctx.Items["altcha_reason"]
(missing / misconfigured / invalid / replayed / expired / etc.)
for downstream middleware to surface in error responses.
- Singleton itself — stateless; one instance shared via factory
registrations under both check interfaces.
AddSvrntyAltcha() registers the check. The verifier is provided by
a transport-specific module (e.g. Svrnty.CQRS.Altcha.Grpc, next).
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
