Input and output bindings in Azure - Practice Problems & Coding Challenges

Challenge - 5 Problems

❓ service_behavior

intermediate

Azure Function Input Binding Behavior

Consider an Azure Function configured with a Blob Storage input binding that triggers when a new blob is added. What will the function receive as input?

A The function receives the blob's content as a stream or string, depending on configuration.

B The function receives only the blob's metadata, not the content.

C The function receives the blob's URL as a string but no content.

D The function receives a trigger event object without any blob data.

💡 Hint

Think about what input bindings provide to the function code.

Input bindings in Azure Functions provide the actual data from the source, such as the blob content, so the function can process it directly.

❓ Configuration

intermediate

Output Binding Configuration for Azure Queue Storage

You want an Azure Function to send messages to an Azure Queue Storage after processing. Which configuration correctly defines the output binding in function.json?

Azure

{
  "bindings": [
    {
      "name": "outputQueueItem",
      "type": "queue",
      "direction": "out",
      "queueName": "myqueue-items",
      "connection": "AzureWebJobsStorage"
    }
  ]
}

A

{
  "name": "outputQueueItem",
  "type": "queueTrigger",
  "direction": "in",
  "queueName": "myqueue-items",
  "connection": "AzureWebJobsStorage"
}

B

{
  "name": "outputQueueItem",
  "type": "queue",
  "direction": "out",
  "queueName": "myqueue-items",
  "connection": "AzureWebJobsStorage"
}

C

{
  "name": "outputQueueItem",
  "type": "blob",
  "direction": "out",
  "path": "myqueue-items",
  "connection": "AzureWebJobsStorage"
}

D

{
  "name": "outputQueueItem",
  "type": "queue",
  "direction": "in",
  "queueName": "myqueue-items",
  "connection": "AzureWebJobsStorage"
}

💡 Hint

Check the binding type and direction for sending messages to a queue.

Output bindings to Azure Queue Storage use type 'queue' with direction 'out'. 'queueTrigger' is for input triggers.

❓ Architecture

advanced

Designing Azure Functions with Multiple Output Bindings

You have an Azure Function that processes data and needs to write results to both a Cosmos DB collection and an Azure Blob Storage container. Which approach correctly supports multiple output bindings?

A Define two output bindings in function.json, one for Cosmos DB and one for Blob Storage, and use separate parameters in the function signature for each output.

B Use a single output binding with type 'cosmosDBBlob' that writes to both services simultaneously.

C Create two separate Azure Functions, each with a single output binding, and call one from the other.

D Write to Cosmos DB inside the function code and configure Blob Storage as an output binding.

💡 Hint

Think about how Azure Functions handle multiple outputs.

Azure Functions support multiple output bindings by defining each in function.json and using separate parameters to output data to each service.

❓ security

advanced

Securing Azure Function Output Bindings

Which is the best practice to secure connection strings used in Azure Function output bindings?

A Use plain text connection strings in function.json without encryption.

B Hardcode connection strings directly in the function code for faster access.

C Store connection strings in a public GitHub repository for easy sharing.

D Store connection strings in Azure Key Vault and reference them via app settings in the function configuration.

💡 Hint

Consider secure storage and access of sensitive information.

Storing secrets in Azure Key Vault and referencing them securely in app settings is the recommended best practice for security.

🧠 Conceptual

expert

Understanding Output Binding Behavior on Function Failure

If an Azure Function with an output binding to Azure Table Storage fails during execution after partially writing data, what is the expected behavior regarding the output binding?

A The output binding operation is rolled back; no partial data is written to Table Storage.

B The function automatically retries and duplicates data in Table Storage.

C Partial data may be written to Table Storage because output bindings are not transactional with function execution.

D The output binding writes data only after the function completes successfully, ensuring atomicity.

💡 Hint

Think about transaction boundaries between function execution and output bindings.

Output bindings in Azure Functions are not transactional with the function execution, so partial writes can occur if the function fails after output binding writes.