07 - Extending Triggers (Flex Consumption)¶

Add queue, timer, and blob triggers with the Node.js v4 APIs and verify the Functions host indexes each binding.

Prerequisites¶

Tool	Version	Purpose
Node.js	20+	Local runtime and package execution
Azure Functions Core Tools	v4	Local host and publishing
Azure CLI	2.61+	Azure resource provisioning and management

Flex Consumption plan basics

Flex Consumption (FC1) supports VNet integration, identity-based storage, per-function scaling, and remote build workflows.

What You'll Build¶

You will add timer, queue, and blob triggers to a Node.js v4 app and verify that the Functions host indexes each binding both locally and in Azure.

Infrastructure Context

Plan: Flex Consumption (FC1) | Network: VNet integration supported

This tutorial adds non-HTTP triggers that require storage queues and blob containers.

flowchart TD
    TIMER["Timer\n(CRON schedule)"] --> FA[Function App\nFlex Consumption FC1]
    QUEUE["Storage Queue\nwork-items"] --> FA
    BLOB["Blob Container\nuploads/{name}"] --> FA
    FA --> PROCESSED["Blob Container\nprocessed/{name}"]

    style FA fill:#0078d4,color:#fff
    style TIMER fill:#E8F5E9
    style QUEUE fill:#FFF3E0
    style BLOB fill:#E3F2FD

flowchart LR
    A[Add timer trigger] --> B[Add queue trigger]
    B --> C[Add blob trigger]
    C --> D[Create storage resources]
    D --> E[Deploy + verify indexing]

Steps¶

Step 1 - Set variables (if not already set)¶

export RG="rg-func-node-flex-demo"
export APP_NAME="<your-function-app-name>"
export STORAGE_NAME="<your-storage-account-name>"

Step 2 - Add a timer trigger¶

Save the following as src/functions/nightlySummary.js:

const { app } = require('@azure/functions');

app.timer('nightlySummary', {
    schedule: '0 0 2 * * *',
    handler: async (_timer, context) => {
        context.log('Nightly summary job fired');
    }
});

Step 3 - Add a queue trigger¶

Save the following as src/functions/orderProcessor.js:

const { app } = require('@azure/functions');

app.storageQueue('orderProcessor', {
    queueName: 'work-items',
    connection: 'QueueStorage',
    handler: async (queueItem, context) => {
        context.log(`Order received: ${JSON.stringify(queueItem)}`);
    }
});

Step 4 - Add a blob trigger¶

Save the following as src/functions/blobIngest.js:

const { app } = require('@azure/functions');

app.storageBlob('blobIngest', {
    path: 'uploads/{name}',
    connection: 'AzureWebJobsStorage',
    handler: async (blob, context) => {
        context.log(`Blob received, size: ${blob.length} bytes`);
    }
});

Step 5 - Create storage resources¶

# Create the queue
az storage queue create \
  --name "work-items" \
  --account-name "$STORAGE_NAME" \
  --auth-mode login

# Create blob containers
az storage container create \
  --name "uploads" \
  --account-name "$STORAGE_NAME" \
  --auth-mode login

az storage container create \
  --name "processed" \
  --account-name "$STORAGE_NAME" \
  --auth-mode login

Step 6 - Verify local trigger indexing¶

cd apps/nodejs && func host start

Step 7 - Deploy and verify in Azure¶

func azure functionapp publish "$APP_NAME"

Step 8 - Test the queue trigger¶

az storage message put \
  --queue-name "work-items" \
  --content '{"orderId":"test-flex-001","item":"widget"}' \
  --account-name "$STORAGE_NAME"

Queue auth mode

If --auth-mode login fails with a permissions error, use --auth-mode key or pass --account-key explicitly. The Storage Queue Data Contributor role is required for login-based queue writes.

Step 9 - Review Flex Consumption-specific notes¶

Flex Consumption supports per-function scaling for queue and blob triggers.
Use long-form CLI flags for maintainable runbooks.
Queue triggers on Flex Consumption benefit from per-function scaling — each function can scale independently.

Verification¶

Local func host start output shows all triggers indexed:

Functions:

    helloHttp: [GET] http://localhost:7071/api/hello/{name?}
    health: [GET] http://localhost:7071/api/health
    nightlySummary: timerTrigger
    orderProcessor: queueTrigger
    blobIngest: blobTrigger

Deployed function list:

az functionapp function list \
  --name "$APP_NAME" \
  --resource-group "$RG" \
  --output table

Clean Up¶

If you are finished with the Flex Consumption tutorials, delete the resource group:

az group delete --name "$RG" --yes --no-wait