Reviewed by Aditya Kumar · Last reviewed 2026-03-24
**Why**: Invalid records corrupt downstream; validation at ingress isolates failures. **Components**: (1) Schema Registry (Avro/Proto/JSON Schema)—versioned schemas; (2) Validate at ingress—Kafka with Schema Registry, API gateway; (3) Check required fields, types, enums; (4)...
Pro-Move: 'We version schemas; invalid events go to DLQ with original payload + error—reprocess after schema fix.'
Why: Invalid records corrupt downstream; validation at ingress isolates failures.
Components: (1) Schema Registry (Avro/Proto/JSON Schema)—versioned schemas; (2) Validate at ingress—Kafka with Schema Registry, API gateway; (3) Check required fields, types, enums; (4) Dead-letter queue for invalid.
Evolution: Backward/forward compatible changes. Confluent Schema Registry; producers validate before produce. For JSON: jsonschema, pydantic. Quarantine invalid; alert on failure rate.
Pro-Move: 'We version schemas; invalid events go to DLQ with original payload + error—reprocess after schema fix.'
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