Claim-Check Pattern - Professional¶
Claim-check is a distributed garbage-collection and integrity protocol around immutable blobs.
Real systems¶
- Amazon S3 gives strong read-after-write consistency but lifecycle deletion is asynchronous.
- Kafka retains the reference log independently of object retention.
- OCI registries use content-addressed manifests and blobs with digest verification.
- Azure Service Bus documents claim-check for payloads beyond broker limits.
At scale, request rate, object-list operations, tiny-object overhead, and cross-region egress dominate. Dashboard referenced versus unreferenced bytes, GET error rate, digest failures, and minimum consumer position before deletion.
Design and operations checklist¶
- Define publish ordering and orphan grace periods.
- Bind immutable digest, schema, encryption, and size to each reference.
- Prove cleanup cannot delete replayable data.
- Test object-store outage and credential rotation.
Test yourself¶
- How would you prove a blob is unreachable before deletion?
- What changes for mutable object keys?
- How do regional failures affect reference placement?
Further reading¶
- Enterprise Integration Patterns, Claim Check.
- Amazon S3 consistency and lifecycle documentation.
- OCI Image Specification: content descriptors.