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

apiVersion: dapr.io/v1alpha1
kind: Component
metadata:
  name: servicebus-pubsub
spec:
  type: pubsub.azure.servicebus
  version: v1
  metadata:
  - name: connectionString # Required when not using Azure Authentication.
    value: "Endpoint=sb://{ServiceBusNamespace}.servicebus.windows.net/;SharedAccessKeyName={PolicyName};SharedAccessKey={Key};EntityPath={ServiceBus}"
  # - name: consumerID # Optional: defaults to the app's own ID
  #   value: "{identifier}" 
  # - name: timeoutInSec # Optional
  #   value: 60
  # - name: handlerTimeoutInSec # Optional
  #   value: 60
  # - name: disableEntityManagement # Optional
  #   value: "false"
  # - name: maxDeliveryCount # Optional
  #   value: 3
  # - name: lockDurationInSec # Optional
  #   value: 60
  # - name: lockRenewalInSec # Optional
  #   value: 20
  # - name: maxActiveMessages # Optional
  #   value: 10000
  # - name: maxConcurrentHandlers # Optional
  #   value: 10
  # - name: defaultMessageTimeToLiveInSec # Optional
  #   value: 10
  # - name: autoDeleteOnIdleInSec # Optional
  #   value: 3600
  # - name: minConnectionRecoveryInSec # Optional
  #   value: 2
  # - name: maxConnectionRecoveryInSec # Optional
  #   value: 300
  # - name: maxRetriableErrorsPerSec # Optional
  #   value: 10
  # - name: publishMaxRetries # Optional
  #   value: 5
  # - name: publishInitialRetryInternalInMs # Optional
  #   value: 500

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

Spec metadata fields

Field Required Details Example
connectionString Y Shared 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}
namespaceName N Parameter 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"
consumerID N Consumer 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.
timeoutInSec N Timeout for sending messages and for management operations. Default: 60 30
handlerTimeoutInSec N Timeout for invoking the app’s handler. Default: 60 30
disableEntityManagement N When set to true, topics and subscriptions do not get created automatically. Default: "false" "true", "false"
maxDeliveryCount N Defines the number of attempts the server will make to deliver a message. Default set by server 10
lockDurationInSec N Defines the length in seconds that a message will be locked for before expiring. Default set by server 30
lockRenewalInSec N Defines the frequency at which buffered message locks will be renewed. Default: 20. 20
maxActiveMessages N Defines 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: 10000 2000
maxConcurrentHandlers N Defines the maximum number of concurrent message handlers. 10
defaultMessageTimeToLiveInSec N Default message time to live. 10
autoDeleteOnIdleInSec N Time in seconds to wait before auto deleting idle subscriptions. 3600
minConnectionRecoveryInSec N Minimum interval (in seconds) to wait before attempting to reconnect to Azure Service Bus in case of a connection failure. Default: 2 5
maxConnectionRecoveryInSec N Maximum 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
maxRetriableErrorsPerSec N Maximum 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: 10 10
publishMaxRetries N The max number of retries for when Azure Service Bus responds with “too busy” in order to throttle messages. Defaults: 5 5
publishInitialRetryInternalInMs N Time in milliseconds for the initial exponential backoff when Azure Service Bus throttle messages. Defaults: 500 500

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

apiVersion: dapr.io/v1alpha1
kind: Component
metadata:
  name: servicebus-pubsub
spec:
  type: pubsub.azure.servicebus
  version: v1
  metadata:
  - name: namespaceName
    # Required when using Azure Authentication.
    # Must be a fully-qualified domain name
    value: "servicebusnamespace.servicebus.windows.net"
  - name: azureTenantId
    value: "***"
  - name: azureClientId
    value: "***"
  - name: azureClientSecret
    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.