BenchMark Quizzes by MDFT Pro

Analyze Queue-Triggered Azure Function Code

You work as a Serverless Application Developer for MDFT Pro, a well-known training agency that delivers certification courses to students worldwide. Mark, the Integration Solutions Architect, has developed an order processing system where the Student Enrollment Portal web application places course enrollment orders into an Azure Storage Queue named “incoming-orders”. You’re reviewing an Azure Function App that processes these orders and stores them in Azure Table Storage for reporting and analytics. The function is triggered by the queue and uses Visual Studio for development.

public static class OrderProcessor
{
	[FunctionName("ProcessOrders")]
	public static void ProcessOrders(
		[QueueTrigger("incoming-orders")] CloudQueueMessage item,
		[Table("Orders")] ICollector<Order> tableBindings,
		TraceWriter log)
	{
		log.Info($"Order: {item.Id}");
		log.Info($"Insertion Time: {item.InsertionTime}");
		log.Info($"Expiration Time: {item.ExpirationTime}");
		tableBindings.Add(JsonConvert.DeserializeObject<Order>(item.AsString));
	}
}

Which three statements correctly describe the behavior of this Azure Function code?

Choose all correct answers from the options below.

Explanations for each answer:

The code will log the time that the order was processed from the queue is incorrect. The code logs item.InsertionTime, which is when the message was originally added to the queue, not when it was processed. To log the processing time, you would need to use DateTime.UtcNow or a similar current timestamp, not a property from the queue message.
When the ProcessOrders function fails, the function will retry up to five times for a given order, including the first try is correct. Azure Functions with queue triggers automatically retry failed messages. The default retry behavior for queue triggers is 5 attempts total (the initial attempt plus 4 retries). After 5 failures, the message is moved to a poison queue for manual investigation.
When there are multiple orders in the queue, a batch of orders will be retrieved from the queue and the ProcessOrders function will run multiple instances concurrently to process the orders is correct. Queue-triggered functions automatically scale out to process messages concurrently. The Functions runtime retrieves multiple messages in batches (default 16 for storage queues) and creates concurrent function instances to process them in parallel, improving throughput for high-volume scenarios like processing student course orders.
The ProcessOrders function will output the order to an Orders table in Azure Table Storage is correct. The [Table('Orders')] output binding with ICollector<Order> automatically inserts items into Azure Table Storage. When tableBindings.Add() is called with the deserialized Order object, the binding handles writing the data to the 'Orders' table, providing a declarative way to store processed orders.

Learn more about Queue Triggers:

Storage Queue Triggers

Practice Exam

Analyze Queue-Triggered Azure Function Code

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