Azure Service Bus

Detailed documentation on the Azure Service Bus pubsub component

Component format

To setup Azure Service Bus pubsub create a component of type pubsub.azure.servicebus. See this guide on how to create and apply a pubsub configuration.

Connection String Authentication

  1. apiVersion: dapr.io/v1alpha1
  2. kind: Component
  3. metadata:
  4. name: servicebus-pubsub
  5. spec:
  6. type: pubsub.azure.servicebus
  7. version: v1
  8. metadata:
  9. - name: connectionString # Required when not using Azure Authentication.
  10. value: "Endpoint=sb://{ServiceBusNamespace}.servicebus.windows.net/;SharedAccessKeyName={PolicyName};SharedAccessKey={Key};EntityPath={ServiceBus}"
  11. # - name: consumerID # Optional: defaults to the app's own ID
  12. # value: "{identifier}"
  13. # - name: timeoutInSec # Optional
  14. # value: 60
  15. # - name: handlerTimeoutInSec # Optional
  16. # value: 60
  17. # - name: disableEntityManagement # Optional
  18. # value: "false"
  19. # - name: maxDeliveryCount # Optional
  20. # value: 3
  21. # - name: lockDurationInSec # Optional
  22. # value: 60
  23. # - name: lockRenewalInSec # Optional
  24. # value: 20
  25. # - name: maxActiveMessages # Optional
  26. # value: 10000
  27. # - name: maxConcurrentHandlers # Optional
  28. # value: 10
  29. # - name: defaultMessageTimeToLiveInSec # Optional
  30. # value: 10
  31. # - name: autoDeleteOnIdleInSec # Optional
  32. # value: 3600
  33. # - name: minConnectionRecoveryInSec # Optional
  34. # value: 2
  35. # - name: maxConnectionRecoveryInSec # Optional
  36. # value: 300
  37. # - name: maxRetriableErrorsPerSec # Optional
  38. # value: 10
  39. # - name: publishMaxRetries # Optional
  40. # value: 5
  41. # - name: publishInitialRetryInternalInMs # Optional
  42. # value: 500

NOTE: The above settings are shared across all topics that use this component.

Warning

The above example uses secrets as plain strings. It is recommended to use a secret store for the secrets as described here.

Spec metadata fields

FieldRequiredDetailsExample
connectionStringYShared access policy connection-string for the Service Bus. Required unless using Azure AD authentication.Endpoint=sb://{ServiceBusNamespace}.servicebus.windows.net/;SharedAccessKeyName={PolicyName};SharedAccessKey={Key};EntityPath={ServiceBus}
namespaceNameNParameter to set the address of the Service Bus namespace, as a fully-qualified domain name. Required if using Azure AD authentication.“namespace.servicebus.windows.net”
consumerIDNConsumer ID a.k.a consumer tag organizes one or more consumers into a group. Consumers with the same consumer ID work as one virtual consumer, i.e. a message is processed only once by one of the consumers in the group. If the consumer ID is not set, the dapr runtime will set it to the dapr application ID.
timeoutInSecNTimeout for sending messages and for management operations. Default: 6030
handlerTimeoutInSecNTimeout for invoking the app’s handler. Default: 6030
disableEntityManagementNWhen set to true, topics and subscriptions do not get created automatically. Default: “false”“true”, “false”
maxDeliveryCountNDefines the number of attempts the server will make to deliver a message. Default set by server10
lockDurationInSecNDefines the length in seconds that a message will be locked for before expiring. Default set by server30
lockRenewalInSecNDefines the frequency at which buffered message locks will be renewed. Default: 20.20
maxActiveMessagesNDefines the maximum number of messages to be processing or in the buffer at once. This should be at least as big as the maximum concurrent handlers. Default: 100002000
maxConcurrentHandlersNDefines the maximum number of concurrent message handlers.10
defaultMessageTimeToLiveInSecNDefault message time to live.10
autoDeleteOnIdleInSecNTime in seconds to wait before auto deleting idle subscriptions.3600
minConnectionRecoveryInSecNMinimum interval (in seconds) to wait before attempting to reconnect to Azure Service Bus in case of a connection failure. Default: 25
maxConnectionRecoveryInSecNMaximum interval (in seconds) to wait before attempting to reconnect to Azure Service Bus in case of a connection failure. After each attempt, the component waits a random number of seconds, increasing every time, between the minimum and the maximum. Default: 300 (5 minutes)600
maxRetriableErrorsPerSecNMaximum number of retriable errors that are processed per second. If a message fails to be processed with a retriable error, the component adds a delay before it starts processing another message, to avoid immediately re-processing messages that have failed. Default: 1010
publishMaxRetriesNThe max number of retries for when Azure Service Bus responds with “too busy” in order to throttle messages. Defaults: 55
publishInitialRetryInternalInMsNTime in milliseconds for the initial exponential backoff when Azure Service Bus throttle messages. Defaults: 500500

Azure Active Directory (AAD) authentication

The Azure Service Bus pubsub component supports authentication using all Azure Active Directory mechanisms, including Managed Identities. For further information and the relevant component metadata fields to provide depending on the choice of AAD authentication mechanism, see the docs for authenticating to Azure.

Example Configuration

  1. apiVersion: dapr.io/v1alpha1
  2. kind: Component
  3. metadata:
  4. name: servicebus-pubsub
  5. spec:
  6. type: pubsub.azure.servicebus
  7. version: v1
  8. metadata:
  9. - name: namespaceName
  10. # Required when using Azure Authentication.
  11. # Must be a fully-qualified domain name
  12. value: "servicebusnamespace.servicebus.windows.net"
  13. - name: azureTenantId
  14. value: "***"
  15. - name: azureClientId
  16. value: "***"
  17. - name: azureClientSecret
  18. value: "***"

Message metadata

Azure Service Bus messages extend the Dapr message format with additional contextual metadata. Some metadata fields are set by Azure Service Bus itself (read-only) and others can be set by the client when publishing a message.

Sending a message with metadata

To set Azure Service Bus metadata when sending a message, set the query parameters on the HTTP request or the gRPC metadata as documented here.

  • metadata.MessageId
  • metadata.CorrelationId
  • metadata.SessionId
  • metadata.Label
  • metadata.ReplyTo
  • metadata.PartitionKey
  • metadata.To
  • metadata.ContentType
  • metadata.ScheduledEnqueueTimeUtc
  • metadata.ReplyToSessionId

NOTE: The metadata.MessageId property does not set the id property of the cloud event and should be treated in isolation.

Receiving a message with metadata

When Dapr calls your application, it will attach Azure Service Bus message metadata to the request using either HTTP headers or gRPC metadata. In addition to the settable metadata listed above, you can also access the following read-only message metadata.

  • metadata.DeliveryCount
  • metadata.LockedUntilUtc
  • metadata.LockToken
  • metadata.EnqueuedTimeUtc
  • metadata.SequenceNumber

To find out more details on the purpose of any of these metadata properties, please refer to the official Azure Service Bus documentation.

Note that all times are populated by the server and are not adjusted for clock skews.

Create an Azure Service Bus

Follow the instructions here on setting up Azure Service Bus Topics.

Last modified July 27, 2022: Remove namespace element from component examples (#2647) (ff9de5c8)