azure.servicebus.aio package¶
-
class
azure.servicebus.aio.
ReceivedMessage
(message: uamqp.message.Message, receive_mode: azure.servicebus._common.constants.ReceiveMode = <ReceiveMode.PeekLock: <ReceiverSettleMode.PeekLock: 1>>, **kwargs: Any)[source]¶ A Service Bus Message received from service side.
-
async
abandon
() → None[source]¶ Abandon the message.
This message will be returned to the queue and made available to be received again.
- Return type
- Raises
~azure.servicebus.exceptions.MessageAlreadySettled if the message has been settled.
- Raises
~azure.servicebus.exceptions.MessageLockExpired if message lock has already expired.
- Raises
~azure.servicebus.exceptions.MessageSettleFailed if message settle operation fails.
-
async
complete
() → None[source]¶ Complete the message.
This removes the message from the queue.
- Return type
- Raises
~azure.servicebus.exceptions.MessageAlreadySettled if the message has been settled.
- Raises
~azure.servicebus.exceptions.MessageLockExpired if message lock has already expired.
- Raises
~azure.servicebus.exceptions.SessionLockExpired if session lock has already expired.
- Raises
~azure.servicebus.exceptions.MessageSettleFailed if message settle operation fails.
-
async
dead_letter
(reason: Optional[str] = None, error_description: Optional[str] = None) → None[source]¶ Move the message to the Dead Letter queue.
The Dead Letter queue is a sub-queue that can be used to store messages that failed to process correctly, or otherwise require further inspection or processing. The queue can also be configured to send expired messages to the Dead Letter queue.
- Parameters
- Return type
- Raises
~azure.servicebus.exceptions.MessageAlreadySettled if the message has been settled.
- Raises
~azure.servicebus.exceptions.MessageLockExpired if message lock has already expired.
- Raises
~azure.servicebus.exceptions.MessageSettleFailed if message settle operation fails.
-
async
defer
() → None[source]¶ Defers the message.
This message will remain in the queue but must be requested specifically by its sequence number in order to be received.
- Return type
- Raises
~azure.servicebus.exceptions.MessageAlreadySettled if the message has been settled.
- Raises
~azure.servicebus.exceptions.MessageLockExpired if message lock has already expired.
- Raises
~azure.servicebus.exceptions.MessageSettleFailed if message settle operation fails.
-
async
renew_lock
() → datetime.datetime[source]¶ Renew the message lock.
This will maintain the lock on the message to ensure it is not returned to the queue to be reprocessed. In order to complete (or otherwise settle) the message, the lock must be maintained. Messages received via ReceiveAndDelete mode are not locked, and therefore cannot be renewed. This operation can also be performed as an asynchronous background task by registering the message with an azure.servicebus.aio.AutoLockRenew instance. This operation is only available for non-sessionful messages.
- Returns
The utc datetime the lock is set to expire at.
- Return type
- Raises
TypeError if the message is sessionful.
- Raises
~azure.servicebus.exceptions.MessageLockExpired is message lock has already expired.
- Raises
~azure.servicebus.exceptions.SessionLockExpired if session lock has already expired.
- Raises
~azure.servicebus.exceptions.MessageAlreadySettled is message has already been settled.
-
property
content_type
¶ The content type descriptor.
Optionally describes the payload of the message, with a descriptor following the format of RFC2045, Section 5, for example “application/json”.
- Return type
-
property
correlation_id
¶ The correlation identifier.
Allows an application to specify a context for the message for the purposes of correlation, for example reflecting the MessageId of a message that is being replied to.
See Message Routing and Correlation in https://docs.microsoft.com/azure/service-bus-messaging/service-bus-messages-payloads?#message-routing-and-correlation.
- Return type
-
property
dead_letter_error_description
¶ Dead letter error description, when the message is received from a deadletter subqueue of an entity.
- Return type
-
property
dead_letter_reason
¶ Dead letter reason, when the message is received from a deadletter subqueue of an entity.
- Return type
-
property
dead_letter_source
¶ The name of the queue or subscription that this message was enqueued on, before it was deadlettered. This property is only set in messages that have been dead-lettered and subsequently auto-forwarded from the dead-letter queue to another entity. Indicates the entity in which the message was dead-lettered.
- Return type
-
property
delivery_count
¶ Number of deliveries that have been attempted for this message. The count is incremented when a message lock expires or the message is explicitly abandoned by the receiver.
- Return type
-
property
enqueued_sequence_number
¶ For messages that have been auto-forwarded, this property reflects the sequence number that had first been assigned to the message at its original point of submission.
- Return type
-
property
enqueued_time_utc
¶ The UTC datetime at which the message has been accepted and stored in the entity.
- Return type
-
property
expires_at_utc
¶ The UTC datetime at which the message is marked for removal and no longer available for retrieval from the entity due to expiration. Expiry is controlled by the Message.time_to_live property. This property is computed from Message.enqueued_time_utc + Message.time_to_live.
- Return type
-
property
label
¶ The application specific label.
This property enables the application to indicate the purpose of the message to the receiver in a standardized fashion, similar to an email subject line.
- Return type
-
property
lock_token
¶ The lock token for the current message serving as a reference to the lock that is being held by the broker in PeekLock mode.
-
property
locked_until_utc
¶ The UTC datetime until which the message will be locked in the queue/subscription. When the lock expires, delivery count of hte message is incremented and the message is again available for retrieval.
- Return type
-
property
message_id
¶ The id to identify the message.
The message identifier is an application-defined value that uniquely identifies the message and its payload. The identifier is a free-form string and can reflect a GUID or an identifier derived from the application context. If enabled, the duplicate detection (see https://docs.microsoft.com/azure/service-bus-messaging/duplicate-detection)
feature identifies and removes second and further submissions of messages with the same message id.
- Return type
-
property
partition_key
¶ The partition key for sending a message to a partitioned entity.
Setting this value enables assigning related messages to the same internal partition, so that submission sequence order is correctly recorded. The partition is chosen by a hash function over this value and cannot be chosen directly.
See Partitioned queues and topics in https://docs.microsoft.com/azure/service-bus-messaging/service-bus-partitioning.
- Return type
-
property
reply_to
¶ The address of an entity to send replies to.
This optional and application-defined value is a standard way to express a reply path to the receiver of the message. When a sender expects a reply, it sets the value to the absolute or relative path of the queue or topic it expects the reply to be sent to.
See Message Routing and Correlation in https://docs.microsoft.com/azure/service-bus-messaging/service-bus-messages-payloads?#message-routing-and-correlation.
- Return type
-
property
reply_to_session_id
¶ The session identifier augmenting the reply_to address.
This value augments the reply_to information and specifies which session id should be set for the reply when sent to the reply entity.
See Message Routing and Correlation in https://docs.microsoft.com/azure/service-bus-messaging/service-bus-messages-payloads?#message-routing-and-correlation.
- Return type
-
property
scheduled_enqueue_time_utc
¶ The utc scheduled enqueue time to the message.
This property can be used for scheduling when sending a message through ServiceBusSender.send method. If cancelling scheduled messages is required, you should use the ServiceBusSender.schedule method, which returns sequence numbers that can be used for future cancellation. scheduled_enqueue_time_utc is None if not set.
- Return type
-
property
sequence_number
¶ The unique number assigned to a message by Service Bus. The sequence number is a unique 64-bit integer assigned to a message as it is accepted and stored by the broker and functions as its true identifier. For partitioned entities, the topmost 16 bits reflect the partition identifier. Sequence numbers monotonically increase. They roll over to 0 when the 48-64 bit range is exhausted.
- Return type
-
property
session_id
¶ The session identifier of the message for a sessionful entity.
For sessionful entities, this application-defined value specifies the session affiliation of the message. Messages with the same session identifier are subject to summary locking and enable exact in-order processing and demultiplexing. For non-sessionful entities, this value is ignored.
See Message Sessions in https://docs.microsoft.com/azure/service-bus-messaging/message-sessions.
- Return type
-
property
time_to_live
¶ The life duration of a message.
This value is the relative duration after which the message expires, starting from the instant the message has been accepted and stored by the broker, as captured in enqueued_time_utc. When not set explicitly, the assumed value is the DefaultTimeToLive for the respective queue or topic. A message-level time-to-live value cannot be longer than the entity’s time-to-live setting and it is silently adjusted if it does.
See Expiration in https://docs.microsoft.com/azure/service-bus-messaging/message-expiration
- Return type
-
property
to
¶ The to address.
This property is reserved for future use in routing scenarios and presently ignored by the broker itself. Applications can use this value in rule-driven auto-forward chaining scenarios to indicate the intended logical destination of the message.
See https://docs.microsoft.com/azure/service-bus-messaging/service-bus-auto-forwarding for more details.
- Return type
-
property
via_partition_key
¶ The partition key for sending a message into an entity via a partitioned transfer queue.
If a message is sent via a transfer queue in the scope of a transaction, this value selects the transfer queue partition: This is functionally equivalent to partition_key and ensures that messages are kept together and in order as they are transferred.
See Transfers and Send Via in https://docs.microsoft.com/azure/service-bus-messaging/service-bus-transactions#transfers-and-send-via.
- Return type
-
async
-
class
azure.servicebus.aio.
ServiceBusClient
(fully_qualified_namespace: str, credential: TokenCredential, **kwargs: Any)[source]¶ The ServiceBusClient class defines a high level interface for getting ServiceBusSender and ServiceBusReceiver.
- Variables
fully_qualified_namespace (str) – The fully qualified host name for the Service Bus namespace. The namespace format is: <yournamespace>.servicebus.windows.net.
- Parameters
fully_qualified_namespace (str) – The fully qualified host name for the Service Bus namespace. The namespace format is: <yournamespace>.servicebus.windows.net.
credential (TokenCredential) – The credential object used for authentication which implements a particular interface for getting tokens. It accepts credential objects generated by the azure-identity library and objects that implement the get_token(self, *scopes) method.
- Keyword Arguments
logging_enable (bool) – Whether to output network trace logs to the logger. Default is False.
transport_type (TransportType) – The type of transport protocol that will be used for communicating with the Service Bus service. Default is TransportType.Amqp.
http_proxy (dict) – HTTP proxy settings. This must be a dictionary with the following keys: ‘proxy_hostname’ (str value) and ‘proxy_port’ (int value). Additionally the following keys may also be present: ‘username’, ‘password’.
user_agent (str) – If specified, this will be added in front of the built-in user agent string.
retry_total (int) – The total number of attempts to redo a failed operation when an error occurs. Default value is 3.
retry_backoff_factor (float) – Delta back-off internal in the unit of second between retries. Default value is 0.8.
retry_backoff_max (float) – Maximum back-off interval in the unit of second. Default value is 120.
Example:
import os from azure.servicebus.aio import ServiceBusClient, ServiceBusSharedKeyCredential fully_qualified_namespace = os.environ['SERVICE_BUS_FULLY_QUALIFIED_NAMESPACE'] shared_access_policy = os.environ['SERVICE_BUS_SAS_POLICY'] shared_access_key = os.environ['SERVICE_BUS_SAS_KEY'] servicebus_client = ServiceBusClient( fully_qualified_namespace=fully_qualified_namespace, credential=ServiceBusSharedKeyCredential( shared_access_policy, shared_access_key ) )
-
async
close
() → None[source]¶ Close down the ServiceBus client. All spawned senders, receivers and underlying connection will be shutdown.
- Returns
None
-
classmethod
from_connection_string
(conn_str: str, **kwargs: Any) → azure.servicebus.aio._servicebus_client_async.ServiceBusClient[source]¶ Create a ServiceBusClient from a connection string.
- Parameters
conn_str (str) – The connection string of a Service Bus.
- Keyword Arguments
logging_enable (bool) – Whether to output network trace logs to the logger. Default is False.
transport_type (TransportType) – The type of transport protocol that will be used for communicating with the Service Bus service. Default is TransportType.Amqp.
http_proxy (dict) – HTTP proxy settings. This must be a dictionary with the following keys: ‘proxy_hostname’ (str value) and ‘proxy_port’ (int value). Additionally the following keys may also be present: ‘username’, ‘password’.
user_agent (str) – If specified, this will be added in front of the built-in user agent string.
retry_total (int) – The total number of attempts to redo a failed operation when an error occurs. Default value is 3.
retry_backoff_factor (float) – Delta back-off internal in the unit of second between retries. Default value is 0.8.
retry_backoff_max (float) – Maximum back-off interval in the unit of second. Default value is 120.
- Return type
Example:
import os from azure.servicebus.aio import ServiceBusClient servicebus_connection_str = os.environ['SERVICE_BUS_CONNECTION_STR'] servicebus_client = ServiceBusClient.from_connection_string(conn_str=servicebus_connection_str)
-
get_queue_receiver
(queue_name: str, **kwargs: Any) → azure.servicebus.aio._servicebus_receiver_async.ServiceBusReceiver[source]¶ Get ServiceBusReceiver for the specific queue.
- Parameters
queue_name (str) – The path of specific Service Bus Queue the client connects to.
- Keyword Arguments
sub_queue (Optional[SubQueue]) – If specified, the subqueue this receiver will connect to. This includes the DeadLetter and TransferDeadLetter queues, holds messages that can’t be delivered to any receiver or messages that can’t be processed. The default is None, meaning connect to the primary queue.
receive_mode (ReceiveMode) – The mode with which messages will be retrieved from the entity. The two options are PeekLock and ReceiveAndDelete. Messages received with PeekLock must be settled within a given lock period before they will be removed from the queue. Messages received with ReceiveAndDelete will be immediately removed from the queue, and cannot be subsequently rejected or re-received if the client fails to process the message. The default mode is PeekLock.
max_wait_time (float) – The timeout in seconds between received messages after which the receiver will automatically stop receiving. The default value is 0, meaning no timeout.
prefetch_count (int) – The maximum number of messages to cache with each request to the service. This setting is only for advanced performance tuning. Increasing this value will improve message throughput performance but increase the chance that messages will expire while they are cached if they’re not processed fast enough. The default value is 0, meaning messages will be received from the service and processed one at a time. In the case of prefetch_count being 0, ServiceBusReceiver.receive would try to cache max_message_count (if provided) within its request to the service.
- Return type
Example:
import os from azure.servicebus.aio import ServiceBusClient servicebus_connection_str = os.environ['SERVICE_BUS_CONNECTION_STR'] queue_name = os.environ['SERVICE_BUS_QUEUE_NAME'] servicebus_client = ServiceBusClient.from_connection_string(conn_str=servicebus_connection_str) async with servicebus_client: queue_receiver = servicebus_client.get_queue_receiver(queue_name=queue_name)
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get_queue_sender
(queue_name: str, **kwargs: Any) → azure.servicebus.aio._servicebus_sender_async.ServiceBusSender[source]¶ Get ServiceBusSender for the specific queue.
- Parameters
queue_name (str) – The path of specific Service Bus Queue the client connects to.
- Return type
Example:
import os from azure.servicebus.aio import ServiceBusClient servicebus_connection_str = os.environ['SERVICE_BUS_CONNECTION_STR'] queue_name = os.environ['SERVICE_BUS_QUEUE_NAME'] servicebus_client = ServiceBusClient.from_connection_string(conn_str=servicebus_connection_str) async with servicebus_client: queue_sender = servicebus_client.get_queue_sender(queue_name=queue_name)
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get_queue_session_receiver
(queue_name: str, session_id: Optional[str] = None, **kwargs: Any) → azure.servicebus.aio._servicebus_session_receiver_async.ServiceBusSessionReceiver[source]¶ Get ServiceBusSessionReceiver for the specific queue.
- Parameters
queue_name (str) – The path of specific Service Bus Queue the client connects to.
session_id (str) – A specific session from which to receive. This must be specified for a sessionful entity, otherwise it must be None. In order to receive messages from the next available session, set this to None. The default is None.
- Keyword Arguments
receive_mode (ReceiveMode) – The mode with which messages will be retrieved from the entity. The two options are PeekLock and ReceiveAndDelete. Messages received with PeekLock must be settled within a given lock period before they will be removed from the queue. Messages received with ReceiveAndDelete will be immediately removed from the queue, and cannot be subsequently rejected or re-received if the client fails to process the message. The default mode is PeekLock.
max_wait_time (float) – The timeout in seconds between received messages after which the receiver will automatically stop receiving. The default value is 0, meaning no timeout.
prefetch_count (int) – The maximum number of messages to cache with each request to the service. This setting is only for advanced performance tuning. Increasing this value will improve message throughput performance but increase the chance that messages will expire while they are cached if they’re not processed fast enough. The default value is 0, meaning messages will be received from the service and processed one at a time. In the case of prefetch_count being 0, ServiceBusReceiver.receive would try to cache max_message_count (if provided) within its request to the service.
- Return type
Example:
import os from azure.servicebus.aio import ServiceBusClient servicebus_connection_str = os.environ['SERVICE_BUS_CONNECTION_STR'] queue_name = os.environ['SERVICE_BUS_QUEUE_NAME'] servicebus_client = ServiceBusClient.from_connection_string(conn_str=servicebus_connection_str) async with servicebus_client: queue_sender = servicebus_client.get_queue_sender(queue_name=queue_name)
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get_subscription_receiver
(topic_name: str, subscription_name: str, **kwargs: Any) → azure.servicebus.aio._servicebus_receiver_async.ServiceBusReceiver[source]¶ Get ServiceBusReceiver for the specific subscription under the topic.
- Parameters
- Keyword Arguments
sub_queue (Optional[SubQueue]) – If specified, the subqueue this receiver will connect to. This includes the DeadLetter and TransferDeadLetter queues, holds messages that can’t be delivered to any receiver or messages that can’t be processed. The default is None, meaning connect to the primary queue.
receive_mode (ReceiveMode) – The mode with which messages will be retrieved from the entity. The two options are PeekLock and ReceiveAndDelete. Messages received with PeekLock must be settled within a given lock period before they will be removed from the subscription. Messages received with ReceiveAndDelete will be immediately removed from the subscription, and cannot be subsequently rejected or re-received if the client fails to process the message. The default mode is PeekLock.
max_wait_time (float) – The timeout in seconds between received messages after which the receiver will automatically stop receiving. The default value is 0, meaning no timeout.
prefetch_count (int) – The maximum number of messages to cache with each request to the service. This setting is only for advanced performance tuning. Increasing this value will improve message throughput performance but increase the chance that messages will expire while they are cached if they’re not processed fast enough. The default value is 0, meaning messages will be received from the service and processed one at a time. In the case of prefetch_count being 0, ServiceBusReceiver.receive would try to cache max_message_count (if provided) within its request to the service.
- Return type
Example:
import os from azure.servicebus import ServiceBusClient servicebus_connection_str = os.environ['SERVICE_BUS_CONNECTION_STR'] topic_name = os.environ["SERVICE_BUS_TOPIC_NAME"] subscription_name = os.environ["SERVICE_BUS_SUBSCRIPTION_NAME"] servicebus_client = ServiceBusClient.from_connection_string(conn_str=servicebus_connection_str) async with servicebus_client: subscription_receiver = servicebus_client.get_subscription_receiver( topic_name=topic_name, subscription_name=subscription_name, )
-
get_subscription_session_receiver
(topic_name: str, subscription_name: str, session_id: Optional[str] = None, **kwargs: Any) → azure.servicebus.aio._servicebus_session_receiver_async.ServiceBusSessionReceiver[source]¶ Get ServiceBusReceiver for the specific subscription under the topic.
- Parameters
topic_name (str) – The name of specific Service Bus Topic the client connects to.
subscription_name (str) – The name of specific Service Bus Subscription under the given Service Bus Topic.
session_id (str) – A specific session from which to receive. This must be specified for a sessionful entity, otherwise it must be None. In order to receive messages from the next available session, set this to None. The default is None.
- Keyword Arguments
receive_mode (ReceiveMode) – The mode with which messages will be retrieved from the entity. The two options are PeekLock and ReceiveAndDelete. Messages received with PeekLock must be settled within a given lock period before they will be removed from the subscription. Messages received with ReceiveAndDelete will be immediately removed from the subscription, and cannot be subsequently rejected or re-received if the client fails to process the message. The default mode is PeekLock.
max_wait_time (float) – The timeout in seconds between received messages after which the receiver will automatically stop receiving. The default value is 0, meaning no timeout.
prefetch_count (int) – The maximum number of messages to cache with each request to the service. This setting is only for advanced performance tuning. Increasing this value will improve message throughput performance but increase the chance that messages will expire while they are cached if they’re not processed fast enough. The default value is 0, meaning messages will be received from the service and processed one at a time. In the case of prefetch_count being 0, ServiceBusReceiver.receive would try to cache max_message_count (if provided) within its request to the service.
- Return type
Example:
import os from azure.servicebus import ServiceBusClient servicebus_connection_str = os.environ['SERVICE_BUS_CONNECTION_STR'] topic_name = os.environ["SERVICE_BUS_TOPIC_NAME"] subscription_name = os.environ["SERVICE_BUS_SUBSCRIPTION_NAME"] servicebus_client = ServiceBusClient.from_connection_string(conn_str=servicebus_connection_str) async with servicebus_client: subscription_receiver = servicebus_client.get_subscription_receiver( topic_name=topic_name, subscription_name=subscription_name, )
-
get_topic_sender
(topic_name: str, **kwargs: Any) → azure.servicebus.aio._servicebus_sender_async.ServiceBusSender[source]¶ Get ServiceBusSender for the specific topic.
- Parameters
topic_name (str) – The path of specific Service Bus Topic the client connects to.
- Return type
Example:
import os from azure.servicebus import ServiceBusClient servicebus_connection_str = os.environ['SERVICE_BUS_CONNECTION_STR'] topic_name = os.environ['SERVICE_BUS_TOPIC_NAME'] servicebus_client = ServiceBusClient.from_connection_string(conn_str=servicebus_connection_str) async with servicebus_client: topic_sender = servicebus_client.get_topic_sender(topic_name=topic_name)
-
class
azure.servicebus.aio.
ServiceBusSender
(fully_qualified_namespace: str, credential: TokenCredential, **kwargs: Any)[source]¶ The ServiceBusSender class defines a high level interface for sending messages to the Azure Service Bus Queue or Topic.
- Variables
- Parameters
fully_qualified_namespace (str) – The fully qualified host name for the Service Bus namespace. The namespace format is: <yournamespace>.servicebus.windows.net.
credential (TokenCredential) – The credential object used for authentication which implements a particular interface for getting tokens. It accepts :class: credential objects generated by the azure-identity library and objects that implement the get_token(self, *scopes) method.
- Keyword Arguments
queue_name (str) – The path of specific Service Bus Queue the client connects to. Only one of queue_name or topic_name can be provided.
topic_name (str) – The path of specific Service Bus Topic the client connects to. Only one of queue_name or topic_name can be provided.
logging_enable (bool) – Whether to output network trace logs to the logger. Default is False.
transport_type (TransportType) – The type of transport protocol that will be used for communicating with the Service Bus service. Default is TransportType.Amqp.
http_proxy (dict) – HTTP proxy settings. This must be a dictionary with the following keys: ‘proxy_hostname’ (str value) and ‘proxy_port’ (int value). Additionally the following keys may also be present: ‘username’, ‘password’.
user_agent (str) – If specified, this will be added in front of the built-in user agent string.
Example:
import os from azure.servicebus.aio import ServiceBusSender, ServiceBusSharedKeyCredential fully_qualified_namespace = os.environ['SERVICE_BUS_FULLY_QUALIFIED_NAMESPACE'] shared_access_policy = os.environ['SERVICE_BUS_SAS_POLICY'] shared_access_key = os.environ['SERVICE_BUS_SAS_KEY'] queue_name = os.environ['SERVICE_BUS_QUEUE_NAME'] queue_sender = ServiceBusSender( fully_qualified_namespace=fully_qualified_namespace, credential=ServiceBusSharedKeyCredential( shared_access_policy, shared_access_key ), queue_name=queue_name )
-
async
cancel_scheduled_messages
(sequence_numbers: Union[int, List[int]]) → None[source]¶ Cancel one or more messages that have previously been scheduled and are still pending.
- Parameters
sequence_numbers (int or list[int]) – The sequence numbers of the scheduled messages.
- Return type
- Raises
~azure.servicebus.exceptions.ServiceBusError if messages cancellation failed due to message already cancelled or enqueued.
Example:
async with servicebus_sender: await servicebus_sender.cancel_scheduled_messages(sequence_nums)
-
async
close
() → None¶ Close down the handler connection.
If the handler has already closed, this operation will do nothing. An optional exception can be passed in to indicate that the handler was shutdown due to error.
- Return type
-
async
create_batch
(max_size_in_bytes: Optional[int] = None) → azure.servicebus._common.message.BatchMessage[source]¶ Create a BatchMessage object with the max size of all content being constrained by max_size_in_bytes. The max_size should be no greater than the max allowed message size defined by the service.
- Parameters
max_size_in_bytes (int) – The maximum size of bytes data that a BatchMessage object can hold. By default, the value is determined by your Service Bus tier.
- Return type
Example:
async with servicebus_sender: batch_message = await servicebus_sender.create_batch() batch_message.add(Message("Single message inside batch"))
-
classmethod
from_connection_string
(conn_str: str, **kwargs: Any) → azure.servicebus.aio._servicebus_sender_async.ServiceBusSender[source]¶ Create a ServiceBusSender from a connection string.
- Parameters
conn_str (str) – The connection string of a Service Bus.
- Keyword Arguments
queue_name (str) – The path of specific Service Bus Queue the client connects to.
topic_name (str) – The path of specific Service Bus Topic the client connects to.
logging_enable (bool) – Whether to output network trace logs to the logger. Default is False.
transport_type (TransportType) – The type of transport protocol that will be used for communicating with the Service Bus service. Default is TransportType.Amqp.
http_proxy (dict) – HTTP proxy settings. This must be a dictionary with the following keys: ‘proxy_hostname’ (str value) and ‘proxy_port’ (int value). Additionally the following keys may also be present: ‘username’, ‘password’.
user_agent (str) – If specified, this will be added in front of the built-in user agent string.
- Return type
- Raises
ServiceBusAuthenticationError – Indicates an issue in token/identity validity.
ServiceBusAuthorizationError – Indicates an access/rights related failure.
Example:
import os from azure.servicebus.aio import ServiceBusSender servicebus_connection_str = os.environ['SERVICE_BUS_CONNECTION_STR'] queue_name = os.environ['SERVICE_BUS_QUEUE_NAME'] queue_sender = ServiceBusSender.from_connection_string( conn_str=servicebus_connection_str, queue_name=queue_name )
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async
schedule_messages
(messages: Union[Message, List[Message]], schedule_time_utc: datetime.datetime) → List[int][source]¶ Send Message or multiple Messages to be enqueued at a specific time by the service. Returns a list of the sequence numbers of the enqueued messages. :param messages: The message or list of messages to schedule. :type messages: ~azure.servicebus.Message or list[~azure.servicebus.Message] :param schedule_time_utc: The utc date and time to enqueue the messages. :type schedule_time_utc: ~datetime.datetime :rtype: list[int]
Example:
async with servicebus_sender: scheduled_time_utc = datetime.datetime.utcnow() + datetime.timedelta(seconds=30) scheduled_messages = [Message("Scheduled message") for _ in range(10)] sequence_nums = await servicebus_sender.schedule_messages(scheduled_messages, scheduled_time_utc)
-
async
send_messages
(message: Union[azure.servicebus._common.message.Message, azure.servicebus._common.message.BatchMessage, List[azure.servicebus._common.message.Message]]) → None[source]¶ Sends message and blocks until acknowledgement is received or operation times out.
If a list of messages was provided, attempts to send them as a single batch, throwing a ValueError if they cannot fit in a single batch.
- Parameters
message (Message or BatchMessage or list[Message]) – The ServiceBus message to be sent.
- Return type
- Raises
- class
~azure.servicebus.exceptions.OperationTimeoutError if sending times out.
- class
~azure.servicebus.exceptions.MessageContentTooLarge if the size of the message is over service bus frame size limit.
- class
~azure.servicebus.exceptions.MessageSendFailed if the message fails to send
- class
~azure.servicebus.exceptions.ServiceBusError when other errors happen such as connection error, authentication error, and any unexpected errors. It’s also the top-level root class of above errors.
Example:
async with servicebus_sender: message = Message("Hello World") await servicebus_sender.send_messages(message)
-
class
azure.servicebus.aio.
ServiceBusReceiver
(fully_qualified_namespace: str, credential: TokenCredential, **kwargs: Any)[source]¶ The ServiceBusReceiver class defines a high level interface for receiving messages from the Azure Service Bus Queue or Topic Subscription.
The two primary channels for message receipt are receive() to make a single request for messages, and async for message in receiver: to continuously receive incoming messages in an ongoing fashion.
- Variables
- Parameters
fully_qualified_namespace (str) – The fully qualified host name for the Service Bus namespace. The namespace format is: <yournamespace>.servicebus.windows.net.
credential (TokenCredential) – The credential object used for authentication which implements a particular interface for getting tokens. It accepts :class: credential objects generated by the azure-identity library and objects that implement the get_token(self, *scopes) method.
- Keyword Arguments
queue_name (str) – The path of specific Service Bus Queue the client connects to.
topic_name (str) – The path of specific Service Bus Topic which contains the Subscription the client connects to.
subscription_name (str) – The path of specific Service Bus Subscription under the specified Topic the client connects to.
receive_mode (ReceiveMode) – The mode with which messages will be retrieved from the entity. The two options are PeekLock and ReceiveAndDelete. Messages received with PeekLock must be settled within a given lock period before they will be removed from the queue. Messages received with ReceiveAndDelete will be immediately removed from the queue, and cannot be subsequently abandoned or re-received if the client fails to process the message. The default mode is PeekLock.
max_wait_time (float) – The timeout in seconds between received messages after which the receiver will automatically shutdown. The default value is 0, meaning no timeout.
logging_enable (bool) – Whether to output network trace logs to the logger. Default is False.
transport_type (TransportType) – The type of transport protocol that will be used for communicating with the Service Bus service. Default is TransportType.Amqp.
http_proxy (dict) – HTTP proxy settings. This must be a dictionary with the following keys: ‘proxy_hostname’ (str value) and ‘proxy_port’ (int value). Additionally the following keys may also be present: ‘username’, ‘password’.
user_agent (str) – If specified, this will be added in front of the built-in user agent string.
prefetch_count (int) – The maximum number of messages to cache with each request to the service. This setting is only for advanced performance tuning. Increasing this value will improve message throughput performance but increase the chance that messages will expire while they are cached if they’re not processed fast enough. The default value is 0, meaning messages will be received from the service and processed one at a time. In the case of prefetch_count being 0, ServiceBusReceiver.receive would try to cache max_message_count (if provided) within its request to the service.
Example:
import os from azure.servicebus.aio import ServiceBusReceiver, ServiceBusSharedKeyCredential fully_qualified_namespace = os.environ['SERVICE_BUS_FULLY_QUALIFIED_NAMESPACE'] shared_access_policy = os.environ['SERVICE_BUS_SAS_POLICY'] shared_access_key = os.environ['SERVICE_BUS_SAS_KEY'] queue_name = os.environ['SERVICE_BUS_QUEUE_NAME'] queue_receiver = ServiceBusReceiver( fully_qualified_namespace=fully_qualified_namespace, credential=ServiceBusSharedKeyCredential( shared_access_policy, shared_access_key ), queue_name=queue_name )
-
async
close
() → None[source]¶ Close down the handler connection.
If the handler has already closed, this operation will do nothing. An optional exception can be passed in to indicate that the handler was shutdown due to error.
- Return type
-
classmethod
from_connection_string
(conn_str: str, **kwargs: Any) → azure.servicebus.aio._servicebus_receiver_async.ServiceBusReceiver[source]¶ Create a ServiceBusReceiver from a connection string.
- Parameters
conn_str (str) – The connection string of a Service Bus.
- Keyword Arguments
queue_name (str) – The path of specific Service Bus Queue the client connects to.
topic_name (str) – The path of specific Service Bus Topic which contains the Subscription the client connects to.
subscription_name (str) – The path of specific Service Bus Subscription under the specified Topic the client connects to.
receive_mode (ReceiveMode) – The mode with which messages will be retrieved from the entity. The two options are PeekLock and ReceiveAndDelete. Messages received with PeekLock must be settled within a given lock period before they will be removed from the queue. Messages received with ReceiveAndDelete will be immediately removed from the queue, and cannot be subsequently abandoned or re-received if the client fails to process the message. The default mode is PeekLock.
max_wait_time (float) – The timeout in seconds between received messages after which the receiver will automatically shutdown. The default value is 0, meaning no timeout.
logging_enable (bool) – Whether to output network trace logs to the logger. Default is False.
transport_type (TransportType) – The type of transport protocol that will be used for communicating with the Service Bus service. Default is TransportType.Amqp.
http_proxy (dict) – HTTP proxy settings. This must be a dictionary with the following keys: ‘proxy_hostname’ (str value) and ‘proxy_port’ (int value). Additionally the following keys may also be present: ‘username’, ‘password’.
user_agent (str) – If specified, this will be added in front of the built-in user agent string.
prefetch_count (int) – The maximum number of messages to cache with each request to the service. This setting is only for advanced performance tuning. Increasing this value will improve message throughput performance but increase the chance that messages will expire while they are cached if they’re not processed fast enough. The default value is 0, meaning messages will be received from the service and processed one at a time. In the case of prefetch_count being 0, ServiceBusReceiver.receive would try to cache max_message_count (if provided) within its request to the service.
- Return type
- Raises
ServiceBusAuthenticationError – Indicates an issue in token/identity validity.
ServiceBusAuthorizationError – Indicates an access/rights related failure.
Example:
import os from azure.servicebus.aio import ServiceBusReceiver servicebus_connection_str = os.environ['SERVICE_BUS_CONNECTION_STR'] queue_name = os.environ['SERVICE_BUS_QUEUE_NAME'] queue_receiver = ServiceBusReceiver.from_connection_string( conn_str=servicebus_connection_str, queue_name=queue_name )
-
get_streaming_message_iter
(max_wait_time: float = None) → AsyncIterator[azure.servicebus.aio._async_message.ReceivedMessage][source]¶ Receive messages from an iterator indefinitely, or if a max_wait_time is specified, until such a timeout occurs.
- Parameters
max_wait_time (float) –
Maximum time to wait in seconds for the next message to arrive. If no messages arrive, and no timeout is specified, this call will not return until the connection is closed. If specified, and no messages arrive for the timeout period, the iterator will stop.
:rtype AsyncIterator[ReceivedMessage]
Example:
-
async
peek_messages
(max_message_count=1, sequence_number=0)[source]¶ Browse messages currently pending in the queue.
Peeked messages are not removed from queue, nor are they locked. They cannot be completed, deferred or dead-lettered.
- Parameters
- Return type
Example:
async with servicebus_receiver: messages = await servicebus_receiver.peek_messages() for message in messages: print(str(message))
-
async
receive_deferred_messages
(sequence_numbers: Union[int, List[int]]) → List[azure.servicebus.aio._async_message.ReceivedMessage][source]¶ Receive messages that have previously been deferred.
When receiving deferred messages from a partitioned entity, all of the supplied sequence numbers must be messages from the same partition.
- Parameters
list[int]] sequence_numbers (Union[int,) – A list of the sequence numbers of messages that have been deferred.
- Return type
Example:
async with servicebus_receiver: deferred_sequenced_numbers = [] messages = await servicebus_receiver.receive_messages(max_wait_time=5) for message in messages: deferred_sequenced_numbers.append(message.sequence_number) print(str(message)) await message.defer() received_deferred_msg = await servicebus_receiver.receive_deferred_messages( sequence_numbers=deferred_sequenced_numbers ) for msg in received_deferred_msg: await msg.complete()
-
async
receive_messages
(max_message_count: Optional[int] = None, max_wait_time: Optional[float] = None) → List[azure.servicebus.aio._async_message.ReceivedMessage][source]¶ Receive a batch of messages at once.
This approach is optimal if you wish to process multiple messages simultaneously, or perform an ad-hoc receive as a single call.
Note that the number of messages retrieved in a single batch will be dependent on whether prefetch_count was set for the receiver. If prefetch_count is not set for the receiver, the receiver would try to cache max_message_count (if provided) messages within the request to the service.
This call will prioritize returning quickly over meeting a specified batch size, and so will return as soon as at least one message is received and there is a gap in incoming messages regardless of the specified batch size.
- Parameters
max_message_count (int) – Maximum number of messages in the batch. Actual number returned will depend on prefetch_count size and incoming stream rate.
max_wait_time (float) – Maximum time to wait in seconds for the first message to arrive. If no messages arrive, and no timeout is specified, this call will not return until the connection is closed. If specified, and no messages arrive within the timeout period, an empty list will be returned.
- Return type
Example:
async with servicebus_receiver: messages = await servicebus_receiver.receive_messages(max_wait_time=5) for message in messages: print(str(message)) await message.complete()
-
class
azure.servicebus.aio.
ServiceBusSessionReceiver
(fully_qualified_namespace: str, credential: TokenCredential, **kwargs: Any)[source]¶ The ServiceBusSessionReceiver class defines a high level interface for receiving messages from the Azure Service Bus Queue or Topic Subscription while utilizing a session for FIFO and ownership semantics.
The two primary channels for message receipt are receive() to make a single request for messages, and async for message in receiver: to continuously receive incoming messages in an ongoing fashion.
- Variables
- Parameters
fully_qualified_namespace (str) – The fully qualified host name for the Service Bus namespace. The namespace format is: <yournamespace>.servicebus.windows.net.
credential (TokenCredential) – The credential object used for authentication which implements a particular interface for getting tokens. It accepts :class: credential objects generated by the azure-identity library and objects that implement the get_token(self, *scopes) method.
- Keyword Arguments
queue_name (str) – The path of specific Service Bus Queue the client connects to.
topic_name (str) – The path of specific Service Bus Topic which contains the Subscription the client connects to.
subscription_name (str) – The path of specific Service Bus Subscription under the specified Topic the client connects to.
receive_mode (ReceiveMode) – The mode with which messages will be retrieved from the entity. The two options are PeekLock and ReceiveAndDelete. Messages received with PeekLock must be settled within a given lock period before they will be removed from the queue. Messages received with ReceiveAndDelete will be immediately removed from the queue, and cannot be subsequently abandoned or re-received if the client fails to process the message. The default mode is PeekLock.
session_id (str) – A specific session from which to receive. This must be specified for a sessionful entity, otherwise it must be None. In order to receive messages from the next available session, set this to None. The default is None.
max_wait_time (float) – The timeout in seconds between received messages after which the receiver will automatically shutdown. The default value is 0, meaning no timeout.
logging_enable (bool) – Whether to output network trace logs to the logger. Default is False.
transport_type (TransportType) – The type of transport protocol that will be used for communicating with the Service Bus service. Default is TransportType.Amqp.
http_proxy (dict) – HTTP proxy settings. This must be a dictionary with the following keys: ‘proxy_hostname’ (str value) and ‘proxy_port’ (int value). Additionally the following keys may also be present: ‘username’, ‘password’.
user_agent (str) – If specified, this will be added in front of the built-in user agent string.
prefetch_count (int) – The maximum number of messages to cache with each request to the service. This setting is only for advanced performance tuning. Increasing this value will improve message throughput performance but increase the chance that messages will expire while they are cached if they’re not processed fast enough. The default value is 0, meaning messages will be received from the service and processed one at a time. In the case of prefetch_count being 0, ServiceBusReceiver.receive would try to cache max_message_count (if provided) within its request to the service.
Example:
import os from azure.servicebus.aio import ServiceBusReceiver, ServiceBusSharedKeyCredential fully_qualified_namespace = os.environ['SERVICE_BUS_FULLY_QUALIFIED_NAMESPACE'] shared_access_policy = os.environ['SERVICE_BUS_SAS_POLICY'] shared_access_key = os.environ['SERVICE_BUS_SAS_KEY'] queue_name = os.environ['SERVICE_BUS_QUEUE_NAME'] queue_receiver = ServiceBusReceiver( fully_qualified_namespace=fully_qualified_namespace, credential=ServiceBusSharedKeyCredential( shared_access_policy, shared_access_key ), queue_name=queue_name )
-
async
close
() → None¶ Close down the handler connection.
If the handler has already closed, this operation will do nothing. An optional exception can be passed in to indicate that the handler was shutdown due to error.
- Return type
-
classmethod
from_connection_string
(conn_str: str, **kwargs: Any) → azure.servicebus.aio._servicebus_session_receiver_async.ServiceBusSessionReceiver[source]¶ Create a ServiceBusSessionReceiver from a connection string.
- Parameters
conn_str (str) – The connection string of a Service Bus.
- Keyword Arguments
queue_name (str) – The path of specific Service Bus Queue the client connects to.
topic_name (str) – The path of specific Service Bus Topic which contains the Subscription the client connects to.
subscription_name (str) – The path of specific Service Bus Subscription under the specified Topic the client connects to.
receive_mode (ReceiveMode) – The mode with which messages will be retrieved from the entity. The two options are PeekLock and ReceiveAndDelete. Messages received with PeekLock must be settled within a given lock period before they will be removed from the queue. Messages received with ReceiveAndDelete will be immediately removed from the queue, and cannot be subsequently abandoned or re-received if the client fails to process the message. The default mode is PeekLock.
session_id (str) – A specific session from which to receive. This must be specified for a sessionful entity, otherwise it must be None. In order to receive messages from the next available session, set this to None. The default is None.
max_wait_time (float) – The timeout in seconds between received messages after which the receiver will automatically shutdown. The default value is 0, meaning no timeout.
logging_enable (bool) – Whether to output network trace logs to the logger. Default is False.
transport_type (TransportType) – The type of transport protocol that will be used for communicating with the Service Bus service. Default is TransportType.Amqp.
http_proxy (dict) – HTTP proxy settings. This must be a dictionary with the following keys: ‘proxy_hostname’ (str value) and ‘proxy_port’ (int value). Additionally the following keys may also be present: ‘username’, ‘password’.
user_agent (str) – If specified, this will be added in front of the built-in user agent string.
prefetch_count (int) – The maximum number of messages to cache with each request to the service. This setting is only for advanced performance tuning. Increasing this value will improve message throughput performance but increase the chance that messages will expire while they are cached if they’re not processed fast enough. The default value is 0, meaning messages will be received from the service and processed one at a time. In the case of prefetch_count being 0, ServiceBusReceiver.receive would try to cache max_message_count (if provided) within its request to the service.
- Return type
- Raises
ServiceBusAuthenticationError – Indicates an issue in token/identity validity.
ServiceBusAuthorizationError – Indicates an access/rights related failure.
Example:
import os from azure.servicebus.aio import ServiceBusReceiver servicebus_connection_str = os.environ['SERVICE_BUS_CONNECTION_STR'] queue_name = os.environ['SERVICE_BUS_QUEUE_NAME'] queue_receiver = ServiceBusReceiver.from_connection_string( conn_str=servicebus_connection_str, queue_name=queue_name )
-
get_streaming_message_iter
(max_wait_time: float = None) → AsyncIterator[azure.servicebus.aio._async_message.ReceivedMessage]¶ Receive messages from an iterator indefinitely, or if a max_wait_time is specified, until such a timeout occurs.
- Parameters
max_wait_time (float) –
Maximum time to wait in seconds for the next message to arrive. If no messages arrive, and no timeout is specified, this call will not return until the connection is closed. If specified, and no messages arrive for the timeout period, the iterator will stop.
:rtype AsyncIterator[ReceivedMessage]
Example:
-
async
peek_messages
(max_message_count=1, sequence_number=0)¶ Browse messages currently pending in the queue.
Peeked messages are not removed from queue, nor are they locked. They cannot be completed, deferred or dead-lettered.
- Parameters
- Return type
Example:
async with servicebus_receiver: messages = await servicebus_receiver.peek_messages() for message in messages: print(str(message))
-
async
receive_deferred_messages
(sequence_numbers: Union[int, List[int]]) → List[azure.servicebus.aio._async_message.ReceivedMessage]¶ Receive messages that have previously been deferred.
When receiving deferred messages from a partitioned entity, all of the supplied sequence numbers must be messages from the same partition.
- Parameters
list[int]] sequence_numbers (Union[int,) – A list of the sequence numbers of messages that have been deferred.
- Return type
Example:
async with servicebus_receiver: deferred_sequenced_numbers = [] messages = await servicebus_receiver.receive_messages(max_wait_time=5) for message in messages: deferred_sequenced_numbers.append(message.sequence_number) print(str(message)) await message.defer() received_deferred_msg = await servicebus_receiver.receive_deferred_messages( sequence_numbers=deferred_sequenced_numbers ) for msg in received_deferred_msg: await msg.complete()
-
async
receive_messages
(max_message_count: Optional[int] = None, max_wait_time: Optional[float] = None) → List[azure.servicebus.aio._async_message.ReceivedMessage]¶ Receive a batch of messages at once.
This approach is optimal if you wish to process multiple messages simultaneously, or perform an ad-hoc receive as a single call.
Note that the number of messages retrieved in a single batch will be dependent on whether prefetch_count was set for the receiver. If prefetch_count is not set for the receiver, the receiver would try to cache max_message_count (if provided) messages within the request to the service.
This call will prioritize returning quickly over meeting a specified batch size, and so will return as soon as at least one message is received and there is a gap in incoming messages regardless of the specified batch size.
- Parameters
max_message_count (int) – Maximum number of messages in the batch. Actual number returned will depend on prefetch_count size and incoming stream rate.
max_wait_time (float) – Maximum time to wait in seconds for the first message to arrive. If no messages arrive, and no timeout is specified, this call will not return until the connection is closed. If specified, and no messages arrive within the timeout period, an empty list will be returned.
- Return type
Example:
async with servicebus_receiver: messages = await servicebus_receiver.receive_messages(max_wait_time=5) for message in messages: print(str(message)) await message.complete()
-
property
session
¶ Get the ServiceBusSession object linked with the receiver. Session is only available to session-enabled entities.
- Return type
Example:
async with servicebus_client.get_queue_session_receiver(queue_name=queue_name, session_id=session_id) as receiver: session = receiver.session
-
class
azure.servicebus.aio.
ServiceBusSession
(session_id: str, receiver: Union[ServiceBusSessionReceiver, ServiceBusSessionReceiverAsync], encoding: str = 'UTF-8')[source]¶ The ServiceBusSession is used for manage session states and lock renewal.
Please use the instance variable `session` on the ServiceBusReceiver to get the corresponding ServiceBusSession object linked with the receiver instead of instantiating a ServiceBusSession object directly.
Example:
async with servicebus_client.get_queue_session_receiver(queue_name=queue_name, session_id=session_id) as receiver: session = receiver.session
-
async
get_state
() → str[source]¶ Get the session state.
Returns None if no state has been set.
- Return type
Example:
async with servicebus_client.get_queue_session_receiver(queue_name=queue_name, session_id=session_id) as receiver: session = receiver.session session_state = await session.get_state()
-
async
renew_lock
() → datetime.datetime[source]¶ Renew the session lock.
This operation must be performed periodically in order to retain a lock on the session to continue message processing.
Once the lock is lost the connection will be closed; an expired lock cannot be renewed.
This operation can also be performed as a threaded background task by registering the session with an azure.servicebus.aio.AutoLockRenew instance.
- Returns
The utc datetime the lock is set to expire at.
- Return type
datetime
Example:
async with servicebus_client.get_queue_session_receiver(queue_name=queue_name, session_id=session_id) as receiver: session = receiver.session session_state = await session.renew_lock()
-
async
set_state
(state: Union[str, bytes, bytearray]) → None[source]¶ Set the session state.
Example:
async with servicebus_client.get_queue_session_receiver(queue_name=queue_name, session_id=session_id) as receiver: session = receiver.session session_state = await session.set_state("START")
-
property
locked_until_utc
¶ The time at which this session’s lock will expire.
- Return type
-
async
-
class
azure.servicebus.aio.
AutoLockRenew
(loop: Optional[asyncio.base_events.BaseEventLoop] = None)[source]¶ Auto lock renew.
An asynchronous AutoLockRenew handler for renewing the lock tokens of messages and/or sessions in the background.
- Parameters
loop (BaseEventLoop) – An async event loop.
Example:
from azure.servicebus.aio import AutoLockRenew lock_renewal = AutoLockRenew() async with servicebus_receiver: async for message in servicebus_receiver: lock_renewal.register(message, timeout=60) await process_message(message) await message.complete()
from azure.servicebus.aio import AutoLockRenew lock_renewal = AutoLockRenew() async with servicebus_client.get_queue_session_receiver(queue_name=queue_name, session_id=session_id) as receiver: session = receiver.session # Auto renew session lock for 2 minutes lock_renewal.register(session, timeout=120) async for message in receiver: await process_message(message) await message.complete()
-
async
close
() → None[source]¶ Cease autorenewal by cancelling any remaining open lock renewal futures.
-
register
(renewable: Union[azure.servicebus.aio._async_message.ReceivedMessage, azure.servicebus.aio._servicebus_session_async.ServiceBusSession], timeout: float = 300, on_lock_renew_failure: Optional[Callable[[Union[azure.servicebus.aio._servicebus_session_async.ServiceBusSession, azure.servicebus.aio._async_message.ReceivedMessage], Optional[Exception]], Awaitable[None]]] = None) → None[source]¶ Register a renewable entity for automatic lock renewal.
- Parameters
renewable (Union[ReceivedMessage,ServiceBusSession]) – A locked entity that needs to be renewed.
timeout (float) – A time in seconds that the lock should be maintained for. Default value is 300 (5 minutes).
on_lock_renew_failure (Optional[AsyncLockRenewFailureCallback]) – An async callback may be specified to be called when the lock is lost on the renewable being registered. Default value is None (no callback).