Semantic Conventions for Azure Messaging Systems

Status: Experimental

The Semantic Conventions for Azure Service Bus and Azure Event Hubs extend and override the Messaging Semantic Conventions.

Azure Service Bus

messaging.system MUST be set to "servicebus" and SHOULD be provided at span creation time.

Span attributes

The following additional attributes are defined:

Attribute	Type	Description	Examples	Requirement Level
`messaging.operation.name`	string	Azure Service Bus operation name. [1]	`send`; `receive`; `complete`; `process`; `peek`	`Required`
`error.type`	string	Describes a class of error the operation ended with. [2]	`amqp:decode-error`; `KAFKA_STORAGE_ERROR`; `channel-error`	`Conditionally Required` If and only if the messaging operation has failed.
`messaging.batch.message_count`	int	The number of messages sent, received, or processed in the scope of the batching operation. [3]	`0`; `1`; `2`	`Conditionally Required` [4]
`messaging.destination.name`	string	The message destination name [5]	`MyQueue`; `MyTopic`	`Conditionally Required` [6]
`messaging.destination.subscription.name`	string	Azure Service Bus subscription name.	`subscription-a`	`Conditionally Required` If messages are received from the subscription.
`messaging.operation.type`	string	A string identifying the type of the messaging operation. [7]	`send`; `create`; `receive`	`Conditionally Required` If applicable.
`messaging.servicebus.disposition_status`	string	Describes the settlement type.	`complete`; `abandon`; `dead_letter`	`Conditionally Required` if and only if `messaging.operation` is `settle`.
`messaging.servicebus.message.delivery_count`	int	Number of deliveries that have been attempted for this message.	`2`	`Conditionally Required` [8]
`server.address`	string	Server domain name if available without reverse DNS lookup; otherwise, IP address or Unix domain socket name. [9]	`example.com`; `10.1.2.80`; `/tmp/my.sock`	`Conditionally Required` If available.
`messaging.message.conversation_id`	string	Message correlation Id property.	`MyConversationId`	`Recommended`
`messaging.message.id`	string	A value used by the messaging system as an identifier for the message, represented as a string.	`452a7c7c7c7048c2f887f61572b18fc2`	`Recommended` If span describes operation on a single message.
`messaging.servicebus.message.enqueued_time`	int	The UTC epoch seconds at which the message has been accepted and stored in the entity.	`1701393730`	`Recommended`
`server.port`	int	Server port number. [10]	`80`; `8080`; `443`	`Recommended`

[1]: The operation name SHOULD match one of the following values:

sender operations: send, schedule, cancel_scheduled
transaction operations: create_transaction, commit_transaction, rollback_transaction
receiver operation: receive, peek, receive_deferred, renew_message_lock
settlement operations: abandon, complete, defer, dead_letter, delete
session operations: accept_session, get_session_state, set_session_state, renew_session_lock

If none of the above operation names apply, the attribute SHOULD be set to the name of the client method in snake_case.

[2]: The error.type SHOULD be predictable, and SHOULD have low cardinality.

When error.type is set to a type (e.g., an exception type), its canonical class name identifying the type within the artifact SHOULD be used.

Instrumentations SHOULD document the list of errors they report.

The cardinality of error.type within one instrumentation library SHOULD be low. Telemetry consumers that aggregate data from multiple instrumentation libraries and applications should be prepared for error.type to have high cardinality at query time when no additional filters are applied.

If the operation has completed successfully, instrumentations SHOULD NOT set error.type.

If a specific domain defines its own set of error identifiers (such as HTTP or gRPC status codes), it’s RECOMMENDED to:

Use a domain-specific attribute
Set error.type to capture all errors, regardless of whether they are defined within the domain-specific set or not.

[3]: Instrumentations SHOULD NOT set messaging.batch.message_count on spans that operate with a single message. When a messaging client library supports both batch and single-message API for the same operation, instrumentations SHOULD use messaging.batch.message_count for batching APIs and SHOULD NOT use it for single-message APIs.

[4]: If the span describes an operation on a batch of messages.

[5]: Destination name SHOULD uniquely identify a specific queue, topic or other entity within the broker. If the broker doesn’t have such notion, the destination name SHOULD uniquely identify the broker.

[6]: If span describes operation on a single message or if the value applies to all messages in the batch.

[7]: If a custom value is used, it MUST be of low cardinality.

[8]: If delivery count is available and is bigger than 0.

[9]: Server domain name of the broker if available without reverse DNS lookup; otherwise, IP address or Unix domain socket name.

[10]: When observed from the client side, and when communicating through an intermediary, server.port SHOULD represent the server port behind any intermediaries, for example proxies, if it’s available.

The following attributes can be important for making sampling decisions and SHOULD be provided at span creation time (if provided at all):

error.type has the following list of well-known values. If one of them applies, then the respective value MUST be used; otherwise, a custom value MAY be used.

Value	Description	Stability
`_OTHER`	A fallback error value to be used when the instrumentation doesn’t define a custom value.

messaging.operation.type has the following list of well-known values. If one of them applies, then the respective value MUST be used; otherwise, a custom value MAY be used.

Value	Description	Stability
`create`	A message is created. “Create” spans always refer to a single message and are used to provide a unique creation context for messages in batch sending scenarios.
`process`	One or more messages are processed by a consumer.
`receive`	One or more messages are requested by a consumer. This operation refers to pull-based scenarios, where consumers explicitly call methods of messaging SDKs to receive messages.
`send`	One or more messages are provided for sending to an intermediary. If a single message is sent, the context of the “Send” span can be used as the creation context and no “Create” span needs to be created.
`settle`	One or more messages are settled.

messaging.servicebus.disposition_status has the following list of well-known values. If one of them applies, then the respective value MUST be used; otherwise, a custom value MAY be used.

Value	Description	Stability
`abandon`	Message is abandoned
`complete`	Message is completed
`dead_letter`	Message is sent to dead letter queue
`defer`	Message is deferred

Azure Event Hubs

messaging.system MUST be set to "eventhubs" and SHOULD be provided at span creation time.