Whether a URI may be mirrored off the object at all.
Enforced at BOTH ends -- queueMirror() keeps the queue clean and drainMirrors() refuses again
before touching the bucket, and the redundancy is what matters. A queue row can outlive the rule
that admitted it: a file mirrored while public, then replaced by a private one at the same URI,
leaves a stale put behind. Checking only at enqueue would publish it.
Whether a URI may be mirrored off the object at all.
Enforced at BOTH ends --
queueMirror()keeps the queue clean anddrainMirrors()refuses again before touching the bucket, and the redundancy is what matters. A queue row can outlive the rule that admitted it: a file mirrored while public, then replaced by a private one at the same URI, leaves a staleputbehind. Checking only at enqueue would publish it.