Tutorial: Deploy a Dapr application to Azure Container Apps using the Azure CLI

Dapr (Distributed Application Runtime) helps developers build resilient, reliable microservices. In this tutorial, a sample Dapr application is deployed to Azure Container Apps.

You learn how to:

  • Create a Container Apps environment for your container apps
  • Create an Azure Blob Storage state store for the container app
  • Deploy two apps that produce and consume messages and persist them in the state store
  • Verify the interaction between the two microservices.

With Azure Container Apps, you get a fully managed version of the Dapr APIs when building microservices. When you use Dapr in Azure Container Apps, you can enable sidecars to run next to your microservices that provide a rich set of capabilities. Available Dapr APIs include Service to Service calls, Pub/Sub, Event Bindings, State Stores, and Actors.

In this tutorial, you deploy the same applications from the Dapr Hello World quickstart.

The application consists of:

  • A client (Python) container app to generate messages.
  • A service (Node) container app to consume and persist those messages in a state store

The following architecture diagram illustrates the components that make up this tutorial:

Architecture diagram for Dapr Hello World microservices on Azure Container Apps

Setup

To begin, sign in to Azure. Run the following command, and follow the prompts to complete the authentication process.

az login

Next, install the Azure Container Apps extension for the CLI.

az extension add --name containerapp --upgrade

Now that the current extension or module is installed, register the Microsoft.App namespace.

Note

Azure Container Apps resources have migrated from the Microsoft.Web namespace to the Microsoft.App namespace. Refer to Namespace migration from Microsoft.Web to Microsoft.App in March 2022 for more details.

az provider register --namespace Microsoft.App

Register the Microsoft.OperationalInsights provider for the Azure Monitor Log Analytics workspace if you have not used it before.

az provider register --namespace Microsoft.OperationalInsights

Next, set the following environment variables:

RESOURCE_GROUP="my-container-apps"
LOCATION="canadacentral"
CONTAINERAPPS_ENVIRONMENT="my-environment"

With these variables defined, you can create a resource group to organize the services related to your new container app.

az group create \
  --name $RESOURCE_GROUP \
  --location $LOCATION

With the CLI upgraded and a new resource group available, you can create a Container Apps environment and deploy your container app.

Create an environment

An environment in Azure Container Apps creates a secure boundary around a group of container apps. Container Apps deployed to the same environment are deployed in the same virtual network and write logs to the same Log Analytics workspace.


Individual container apps are deployed to an Azure Container Apps environment. To create the environment, run the following command:

az containerapp env create \
  --name $CONTAINERAPPS_ENVIRONMENT \
  --resource-group $RESOURCE_GROUP \
  --location "$LOCATION"

Set up a state store

Create an Azure Blob Storage account

With the environment deployed, the next step is to deploy an Azure Blob Storage account that is used by one of the microservices to store data. Before deploying the service, you need to choose a name for the storage account. Storage account names must be unique within Azure, from 3 to 24 characters in length and must contain numbers and lowercase letters only.

STORAGE_ACCOUNT_NAME="<storage account name>"

Use the following command to create the Azure Storage account.

az storage account create \
  --name $STORAGE_ACCOUNT_NAME \
  --resource-group $RESOURCE_GROUP \
  --location "$LOCATION" \
  --sku Standard_RAGRS \
  --kind StorageV2

Configure a user-assigned identity for the node app

While Container Apps supports both user-assigned and system-assigned managed identity, a user-assigned identity provides the Dapr-enabled node app with permissions to access the blob storage account.

  1. Create a user-assigned identity.
az identity create --resource-group $RESOURCE_GROUP --name "nodeAppIdentity" --output json

Retrieve the principalId and id properties and store in variables.

PRINCIPAL_ID=$(az identity show -n "nodeAppIdentity" --resource-group $RESOURCE_GROUP --query principalId | tr -d \")
IDENTITY_ID=$(az identity show -n "nodeAppIdentity" --resource-group $RESOURCE_GROUP --query id | tr -d \")
CLIENT_ID=$(az identity show -n "nodeAppIdentity" --resource-group $RESOURCE_GROUP --query clientId | tr -d \")
  1. Assign the Storage Blob Data Contributor role to the user-assigned identity

Retrieve the subscription ID for your current subscription.

SUBSCRIPTION_ID=$(az account show --query id --output tsv)
az role assignment create --assignee $PRINCIPAL_ID  \
--role "Storage Blob Data Contributor" \
--scope "/subscriptions/$SUBSCRIPTION_ID/resourceGroups/$RESOURCE_GROUP/providers/Microsoft.Storage/storageAccounts/$STORAGE_ACCOUNT_NAME"

Configure the state store component

There are multiple ways to authenticate to external resources via Dapr. This example doesn't use the Dapr Secrets API at runtime, but uses an Azure-based state store. Therefore, you can forgo creating a secret store component and instead provide direct access from the node app to the blob store using Managed Identity. If you want to use a non-Azure state store or the Dapr Secrets API at runtime, you could create a secret store component. This component would load runtime secrets so you can reference them at runtime.

Open a text editor and create a config file named statestore.yaml with the properties that you sourced from the previous steps. This file helps enable your Dapr app to access your state store. The following example shows how your statestore.yaml file should look when configured for your Azure Blob Storage account:

# statestore.yaml for Azure Blob storage component
componentType: state.azure.blobstorage
version: v1
metadata:
  - name: accountName
    value: "<STORAGE_ACCOUNT_NAME>"
  - name: containerName
    value: mycontainer
  - name: azureClientId
    value: "<MANAGED_IDENTITY_CLIENT_ID>"
scopes:
  - nodeapp

To use this file, update the placeholders:

  • Replace <STORAGE_ACCOUNT_NAME> with the value of the STORAGE_ACCOUNT_NAME variable you defined. To obtain its value, run the following command:
echo $STORAGE_ACCOUNT_NAME
  • Replace <MANAGED_IDENTITY_CLIENT_ID> with the value of the CLIENT_ID variable you defined. To obtain its value, run the following command:
echo $CLIENT_ID

Navigate to the directory in which you stored the component yaml file and run the following command to configure the Dapr component in the Container Apps environment. For more information about configuring Dapr components, see Configure Dapr components.

az containerapp env dapr-component set \
    --name $CONTAINERAPPS_ENVIRONMENT --resource-group $RESOURCE_GROUP \
    --dapr-component-name statestore \
    --yaml statestore.yaml

Deploy the service application (HTTP web server)

az containerapp create \
  --name nodeapp \
  --resource-group $RESOURCE_GROUP \
  --user-assigned $IDENTITY_ID \
  --environment $CONTAINERAPPS_ENVIRONMENT \
  --image dapriosamples/hello-k8s-node:latest \
  --min-replicas 1 \
  --max-replicas 1 \
  --enable-dapr \
  --dapr-app-id nodeapp \
  --dapr-app-port 3000 \
  --env-vars 'APP_PORT=3000'

By default, the image is pulled from Docker Hub.

Deploy the client application (headless client)

Run the following command to deploy the client container app.

az containerapp create \
  --name pythonapp \
  --resource-group $RESOURCE_GROUP \
  --environment $CONTAINERAPPS_ENVIRONMENT \
  --image dapriosamples/hello-k8s-python:latest \
  --min-replicas 1 \
  --max-replicas 1 \
  --enable-dapr \
  --dapr-app-id pythonapp

Verify the results

Confirm successful state persistence

You can confirm that the services are working correctly by viewing data in your Azure Storage account.

  1. Open the Azure portal in your browser and navigate to your storage account.

  2. Select Containers left side menu.

  3. Select mycontainer.

  4. Verify that you can see the file named order in the container.

  5. Select the file.

  6. Select the Edit tab.

  7. Select the Refresh button to observe how the data automatically updates.

View Logs

Logs from container apps are stored in the ContainerAppConsoleLogs_CL custom table in the Log Analytics workspace. You can view logs through the Azure portal or via the CLI. There may be a small delay initially for the table to appear in the workspace.

Use the following CLI command to view logs using the command line.

LOG_ANALYTICS_WORKSPACE_CLIENT_ID=`az containerapp env show --name $CONTAINERAPPS_ENVIRONMENT --resource-group $RESOURCE_GROUP --query properties.appLogsConfiguration.logAnalyticsConfiguration.customerId --out tsv`

az monitor log-analytics query \
  --workspace $LOG_ANALYTICS_WORKSPACE_CLIENT_ID \
  --analytics-query "ContainerAppConsoleLogs_CL | where ContainerAppName_s == 'nodeapp' and (Log_s contains 'persisted' or Log_s contains 'order') | project ContainerAppName_s, Log_s, TimeGenerated | sort by TimeGenerated | take 5" \
  --out table

The following output demonstrates the type of response to expect from the CLI command.

ContainerAppName_s    Log_s                            TableName      TimeGenerated
--------------------  -------------------------------  -------------  ------------------------
nodeapp               Got a new order! Order ID: 61    PrimaryResult  2021-10-22T21:31:46.184Z
nodeapp               Successfully persisted state.    PrimaryResult  2021-10-22T21:31:46.184Z
nodeapp               Got a new order! Order ID: 62    PrimaryResult  2021-10-22T22:01:57.174Z
nodeapp               Successfully persisted state.    PrimaryResult  2021-10-22T22:01:57.174Z
nodeapp               Got a new order! Order ID: 63    PrimaryResult  2021-10-22T22:45:44.618Z

Clean up resources

Congratulations! You've completed this tutorial. If you'd like to delete the resources created as a part of this walkthrough, run the following command.

Caution

This command deletes the specified resource group and all resources contained within it. If resources outside the scope of this tutorial exist in the specified resource group, they will also be deleted.

az group delete --resource-group $RESOURCE_GROUP

Note

Since pythonapp continuously makes calls to nodeapp with messages that get persisted into your configured state store, it is important to complete these cleanup steps to avoid ongoing billable operations.

Tip

Having issues? Let us know on GitHub by opening an issue in the Azure Container Apps repo.

Next steps