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Author: pyama

exporter/kafkaexporter/README.md

@@ -29,7 +29,7 @@ The following settings can be optionally configured:
 - `resolve_canonical_bootstrap_servers_only` (default = false): Whether to resolve then reverse-lookup broker IPs during startup.
 - `client_id` (default = "sarama"): The client ID to configure the Sarama Kafka client with. The client ID will be used for all produce requests.
 - `topic` (default = otlp_spans for traces, otlp_metrics for metrics, otlp_logs for logs): The name of the kafka topic to export to.
-- `topic_from_attribute`: Specify the attribute name when you want to dynamically obtain the topic name from an attribute. Within the same transmission unit, if there are multiple values for the same attribute, use the first value that can be obtained.
+- `topic_from_attribute` (default = ""): Specify the resource attribute whose value should be used as the message's topic. This option, when set, will take precedence over the default topic.
 - `encoding` (default = otlp_proto): The encoding of the traces sent to kafka. All available encodings:
   - `otlp_proto`: payload is Protobuf serialized from `ExportTraceServiceRequest` if set as a traces exporter or `ExportMetricsServiceRequest` for metrics or `ExportLogsServiceRequest` for logs.
   - `otlp_json`:  payload is JSON serialized from `ExportTraceServiceRequest` if set as a traces exporter or `ExportMetricsServiceRequest` for metrics or `ExportLogsServiceRequest` for logs.