honor offline caching in /v1/status API
#412
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Now, the `/v1/status` API will not try fetch the backend keystore status if: - offline caching is enabled. - the keystore is considered offline. The idea here is that if the cache considered the backend keystore as offline then it is unlikely that a `Status` suceeds. Instead, we can directly return unreachable. Once, the keystore becomes available again, the cache will detect it eventually (on its next health check cycle). Among other things, this improves pod availability when `/v1/status` is used as (part of) readiness probes. (i.e. MinIO) Such probes are now less likely to time out since `/v1/status` returns immediately. However, if the backend keystore becomes unavailable and a `/v1/status` request arrives BEFORE the cache detects that the keystore is offline then these requests may time out. Hence, it is recommended to use readiness probes with a retry threshold > 1. Signed-off-by: Andreas Auernhammer <[email protected]>
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Now, the
/v1/statusAPI will not try fetch the backend keystore status if:The idea here is that if the cache considered the backend keystore as offline then it is unlikely that a
Statussuceeds. Instead, we can directly return unreachable.Once, the keystore becomes available again, the cache will detect it eventually (on its next health check cycle).
Among other things, this improves pod availability when
/v1/statusis used as (part of) readiness probes. (i.e. MinIO) Such probes are now less likely to time out since/v1/statusreturns immediately.However, if the backend keystore becomes unavailable and a
/v1/statusrequest arrives BEFORE the cache detects that the keystore is offline then these requests may time out. Hence, it is recommended to use readiness probes with a retry threshold > 1.