Why serverless patterns matter in Azure - Test Your Understanding

Practice - 5 Tasks

1fill in blank

easy

Complete the code to create an Azure Function app with the correct runtime.

Azure

az functionapp create --resource-group myResourceGroup --consumption-plan-location westus --runtime [1] --name myFunctionApp --storage-account mystorageaccount

Drag options to blanks, or click blank then click option'

Anode

Bpython

Cjava

Ddotnet

Attempts:

3 left

💡 Hint

Common Mistakes

Using a runtime that does not match the function code language.

Forgetting to specify the runtime parameter.

Azure Functions supports multiple runtimes. Here, 'python' is the correct runtime to specify for a Python function app.

2fill in blank

medium

Complete the code to add a trigger to an Azure Function that responds to HTTP requests.

Azure

func new --name HttpTrigger --template [1] --authlevel anonymous

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AHTTP trigger

BBlob trigger

CTimer trigger

DQueue trigger

Attempts:

3 left

💡 Hint

Common Mistakes

Choosing a trigger that responds to storage events instead of HTTP.

Confusing trigger names.

The HTTP trigger allows the function to be invoked by HTTP requests, which is common in serverless patterns.

3fill in blank

hard

Fix the error in the Azure Function app settings to enable Application Insights for monitoring.

Azure

az functionapp update --name myFunctionApp --resource-group myResourceGroup --set [1]=true

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AappInsights.enabled

BapplicationInsightsKey

CapplicationInsights.enabled

DappInsightsKey

Attempts:

3 left

💡 Hint

Common Mistakes

Using incorrect setting names or casing.

Confusing the key with the enabled flag.

The correct setting to enable Application Insights is 'applicationInsights.enabled'.

4fill in blank

hard

Fill both blanks to define a serverless function that triggers on a new blob upload and logs the blob name.

Azure

def main(myblob: func.InputStream):
    logging.info(f"Processing blob: [1]")
    blob_content = [2].read()

Drag options to blanks, or click blank then click option'

Amyblob.name

Bmyblob

Cmyblob.content

Dmyblob.get_blob()

Attempts:

3 left

💡 Hint

Common Mistakes

Trying to call a non-existent method on the blob object.

Using incorrect property names.

The blob's name is accessed with 'myblob.name', and the content is read from 'myblob'.

5fill in blank

hard

Fill all three blanks to configure an Azure Durable Function orchestrator that calls two activity functions sequentially.

Azure

import azure.functions as func
import azure.durable_functions as df

async def orchestrator_function(context: df.DurableOrchestrationContext):
    output1 = await context.call_activity('[1]', None)
    output2 = await context.call_activity('[2]', output1)
    return [3]

main = df.Orchestrator.create(orchestrator_function)

Drag options to blanks, or click blank then click option'

AActivityFunctionA

BActivityFunctionB

C[output1, output2]

Doutput2

Attempts:

3 left

💡 Hint

Common Mistakes

Mixing up the order of activity function calls.

Returning a list instead of the final output.

The orchestrator calls 'ActivityFunctionA' first, then 'ActivityFunctionB' passing the first output, and finally returns the second output.

Practice

1. What is a key benefit of using serverless patterns in Azure applications?

easy

A. Automatic scaling and cost savings

B. Manual server management

C. Fixed monthly billing regardless of usage

D. Requires dedicated hardware setup

Solution

1. Step 1: Understand serverless basics

   Serverless means the cloud provider manages servers and scales automatically.

2. Step 2: Identify benefits of serverless

   This automatic scaling helps save costs because you pay only for what you use.

3. Final Answer:

   Automatic scaling and cost savings -> Option A

4. Quick Check:

   Serverless = automatic scaling + cost savings [OK]

Hint: Serverless means no manual server work, just pay for usage [OK]

Common Mistakes:

• Thinking serverless requires manual server setup
• Assuming fixed billing regardless of usage
• Confusing serverless with dedicated hardware

2. Which Azure service is an example of a serverless compute option?

easy

A. Azure Functions

B. Azure Virtual Machines

C. Azure Kubernetes Service

D. Azure Blob Storage

Solution

1. Step 1: Identify serverless compute services

   Serverless compute runs code without managing servers; Azure Functions is designed for this.

2. Step 2: Compare options

   Virtual Machines and Kubernetes require server management; Blob Storage is for data, not compute.

3. Final Answer:

   Azure Functions -> Option A

4. Quick Check:

   Serverless compute = Azure Functions [OK]

Hint: Azure Functions runs code serverless, VMs do not [OK]

Common Mistakes:

• Choosing Virtual Machines as serverless
• Confusing storage services with compute
• Selecting Kubernetes which needs server management

3. Consider this Azure Function code snippet triggered by an HTTP request:

module.exports = async function (context, req) {
  context.log('Function triggered');
  if (req.query.name) {
    context.res = { body: `Hello, ${req.query.name}!` };
  } else {
    context.res = { status: 400, body: 'Please pass a name' };
  }
};

What will be the response if the request URL is https://example.azurewebsites.net/api/function?name=Alex?

medium

A. Function triggered

B. Please pass a name

C. Hello, Alex!

D. 400 Bad Request

Solution

1. Step 1: Check request query parameter

   The URL includes name=Alex, so req.query.name is 'Alex'.

2. Step 2: Determine response based on condition

   Since req.query.name exists, the function returns Hello, Alex! in the response body.

3. Final Answer:

   Hello, Alex! -> Option C

4. Quick Check:

   Query name present = Hello message [OK]

Hint: If query has name, response says Hello with that name [OK]

Common Mistakes:

• Ignoring query parameters in the URL
• Confusing log output with response body
• Assuming error response without checking condition

4. You wrote an Azure Function to process messages from a queue, but it never triggers. Which is the most likely cause?

medium

A. The function code has a syntax error

B. The function app is running on a VM

C. The queue is empty but the function triggers anyway

D. The function app is not linked to the correct queue trigger

Solution

1. Step 1: Understand queue trigger requirements

   Azure Functions need correct binding to the queue to trigger on new messages.

2. Step 2: Analyze why function never triggers

   If the function is not linked to the right queue, it won't run even if messages exist.

3. Final Answer:

   The function app is not linked to the correct queue trigger -> Option D

4. Quick Check:

   Wrong trigger binding = no function execution [OK]

Hint: Check trigger bindings if function never runs [OK]

Common Mistakes:

• Assuming syntax error without checking bindings
• Thinking function triggers on empty queue
• Confusing serverless with VM hosting

5. You want to build an Azure app that automatically scales based on incoming events and only runs code when needed. Which serverless pattern should you use to achieve this efficiently?

hard

A. Use Azure Kubernetes Service with manual scaling

B. Use Azure Functions triggered by events with consumption plan

C. Deploy a fixed number of Azure Virtual Machines

D. Host a web app on a dedicated App Service Plan

Solution

1. Step 1: Identify serverless pattern for event-driven scaling

   Azure Functions with event triggers and consumption plan scale automatically and run only when events occur.

2. Step 2: Compare other options

   Virtual Machines and Kubernetes require manual scaling; dedicated App Service Plan runs continuously, not event-driven.

3. Final Answer:

   Use Azure Functions triggered by events with consumption plan -> Option B

4. Quick Check:

   Event-driven + auto scale = Azure Functions consumption plan [OK]

Hint: Event-driven auto scale? Choose Azure Functions consumption plan [OK]

Common Mistakes:

• Choosing fixed VM or manual scaling options
• Confusing App Service Plan with serverless consumption
• Ignoring event-driven triggers