Skip to content

Dapr Integration (Distributed Application Runtime)¶

Azure Container Apps provides native Dapr integration, allowing your Python application to easily interact with other services and manage state, publish/subscribe messaging, and secrets.

flowchart TD
    C[Client] --> I[Container Apps Ingress]
    I --> APP[Python App]
    APP <--> DAPR[Dapr Sidecar]
    DAPR --> STATE[State Store]
    DAPR --> PUBSUB["Pub/Sub Broker"]
    DAPR --> SVC[Other Services]

Enabling Dapr¶

To enable Dapr for your container app:

az containerapp dapr enable \
  --name my-python-app \
  --resource-group my-aca-rg \
  --dapr-app-id my-python-service \
  --dapr-app-port 8000

Command	Why it is used
`az containerapp dapr enable ...`	Configures Dapr sidecar settings for the Container App.

How Dapr Works¶

Dapr runs as a sidecar container alongside your application. Your application interacts with Dapr using HTTP or gRPC on localhost.

Python Implementation¶

Use the dapr library in your Python code to interact with Dapr.

State Management¶

from dapr.clients import DaprClient

with DaprClient() as d:
    # Save state
    d.save_state(store_name='statestore', key='order_1', value='{"item": "laptop"}')

    # Get state
    state = d.get_state(store_name='statestore', key='order_1')
    print(state.data)

Publish/Subscribe Messaging¶

from dapr.clients import DaprClient

with DaprClient() as d:
    # Publish a message
    d.publish_event(
        pubsub_name='messagebus',
        topic_name='orders',
        data='{"orderId": 123}',
        data_content_type='application/json'
    )

Dapr Components¶

Configure Dapr components (like state stores or pub/sub brokers) as separate resources in your Bicep/ARM templates. Container Apps then maps these components to your application at runtime.

Why use Dapr?¶

Abstracted Infrastructure: Switch from Redis to Service Bus without changing your application code.
Configurable resiliency: Dapr service invocation can use explicit resiliency policies for retries, timeouts, and circuit breakers. Circuit breakers are not automatic; define and test the policy before relying on it in production.
Enhanced Observability: Dapr automatically collects telemetry for all cross-service communication.

See Also¶

Sources¶