Add OpenTelemetry tracing support to debezium-connector-cassandra #1769
Description
Feature request or enhancement
For feature requests or enhancements, please provide the following information:
Which use case/requirement will be addressed by the proposed feature?
The Cassandra connector currently has no tracing support, making it impossible to correlate CDC events with distributed traces across the pipeline. Other Debezium connectors support tracing via the ActivateTracingSpan SMT, but since the Cassandra connector does not use the Kafka Connect framework, that is unavailable.
Users running Cassandra CDC pipelines need end-to-end observability: knowing when a Cassandra mutation occurred, when it was processed by Debezium, and being able to continue the trace downstream (e.g. into an Elasticsearch Sink or other consumers).
Implementation ideas (optional)
Instrument debezium-connector-cassandra at the Kafka Emitter level, following the same OTEL span conventions used in debezium-core. Two nested OTEL spans would be created per emitted event:
db-log-write: backdated to the Cassandra mutation timestamp (tsMicro), with source attributes:keyspace, table, cluster, commitlog file/position, snapshot flag, connector version.debezium-read: timestamped at Debezium processing time, withopandts_ms.
A trace context is injected into the Kafka ProducerRecord headers (traceparent) so downstream consumers can continue the distributed trace.
A new config property tracing.enabled (default: false) would gate the feature. If tracing is enabled but no OTEL jar is present on the classpath, the connector no-ops rather than failing (same as debezium-core).