* ipn/localapi,ipnlocal,feature/acme,client/local: honour Retry-After on cert rate-limit
serveCert now responds with 429 + Retry-After when the underlying ACME
error is a rate limit, instead of a generic 500. client/local surfaces
this as a typed RateLimitedError with the parsed hint so callers can
back off intelligently.
Updates tailscale/corp#42164
Signed-off-by: chaosinthecrd <tom@tmlabs.co.uk>
* tsweb,feature/acme,ipn/localapi,ipnlocal: generalise cert error → HTTP mapping via tsweb.HTTPStatuser
Introduces a tsweb.HTTPStatuser interface, any error can implement
to describe its intended HTTP response (code, message, headers).
Moves CertRateLimitedError from ipnlocal to feature/acme where it's
constructed, and it now uses HTTPStatuser to return 429 + Retry-After.
serveCert now checks for tsweb.HTTPStatuser rather than the specific
error type, so it no longer needs to know about the ACME rate-limit
type.
Signed-off-by: chaosinthecrd <tom@tmlabs.co.uk>
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Signed-off-by: chaosinthecrd <tom@tmlabs.co.uk>