add rabbitmq to semantic conventions yaml

CHANGELOG.md

@@ -21,6 +21,7 @@ release.
 
 - Fix the inconsistent formatting of semantic convention enums ([#1598](https://github.com/open-telemetry/opentelemetry-specification/pull/1598/))
 - Add details for filling resource for AWS Lambda([#1610](https://github.com/open-telemetry/opentelemetry-specification/pull/1610))
+- Add already specified `messaging.rabbitmq.routing_key` span attribute key to the respective YAML file.
 
 ### Compatibility
 

semantic_conventions/trace/messaging.yaml

@@ -121,6 +121,20 @@ groups:
         Semantic convention for servers that consume messages received from messaging systems
         and always send back replies directed to the producers of these messages.
 
+    - id: messaging.rabbitmq
+      prefix: messaging.rabbitmq
+      extends: messaging
+      brief: >
+        Attributes for RabbitMQ
+      attributes:
+        - id: routing_key
+          type: string
+          required:
+            conditional: Unless it is empty.
+          brief: >
+            RabbitMQ message routing key.
+          examples: 'myKey'
+
     - id: messaging.kafka
       prefix: messaging.kafka
       extends: messaging

specification/trace/semantic_conventions/messaging.md

@@ -189,7 +189,12 @@ Instead span kind should be set to either `CONSUMER` or `SERVER` according to th
 
 In RabbitMQ, the destination is defined by an _exchange_ and a _routing key_.
 `messaging.destination` MUST be set to the name of the exchange. This will be an empty string if the default exchange is used.
-The routing key MUST be provided to the attribute `messaging.rabbitmq.routing_key`, unless it is empty.
+
+<!-- semconv messaging.rabbitmq -->
+| Attribute  | Type | Description  | Examples  | Required |
+|---|---|---|---|---|
+| `messaging.rabbitmq.routing_key` | string | RabbitMQ message routing key. | `myKey` | Unless it is empty. |
+<!-- endsemconv -->
 
 #### Apache Kafka