Explore the essential concepts of integrating object storage with serverless functions using triggers, events, permissions, and best practices. This quiz is designed to help you assess your understanding of connecting cloud storage with compute automation in scalable cloud deployments.
Which action allows you to invoke a Lambda function automatically when a new object is uploaded to a storage bucket?
Explanation: Configuring an event notification with the object creation event is the proper way to trigger Lambda upon file uploads. Scheduling Lambda with cron does not react to object uploads but triggers based on time. Adding a deny bucket policy restricts access rather than creates triggers. Enabling versioning only keeps previous copies and does not initiate function execution.
You want your Lambda function to process files from your storage bucket. Which permission must be granted to the Lambda function?
Explanation: Read access is required so the function can retrieve and process items from the bucket. Write-only access is insufficient because the function cannot read file contents. Delete permissions or administrative access are unnecessary and increase security risk. Principle of least privilege suggests only granting the required read access.
When a Lambda function is triggered by a new storage bucket object, what information is typically included in the event data?
Explanation: Event payloads supply details like the bucket name and object key so the function knows which file caused the event. The event does not contain the whole file’s contents, just reference info. A timestamp might also be present but alone is not useful. Network settings are not included in the event object.
If a Lambda function writes a new file to the same bucket after processing, what risk does this introduce?
Explanation: Writing back to the same bucket can trigger the Lambda again, causing recursion or loops. The bucket is not deleted, and costs increase only if more storage is used, not instantly doubled. File size limits are unaffected by this workflow, but recursion can quickly lead to unintended repeat invocations.
What advantage does integrating Lambda with storage buckets offer for handling varying numbers of uploaded files?
Explanation: Lambda responds to each event, easily scaling up or down depending on workload, which is a key benefit of serverless integration. Manual server management is not needed since operation is automated. Fixed compute resources do not provide this elasticity. Upload speed depends on other factors and is not directly changed by the function.
A company wants to resize image files automatically whenever users upload photos into a storage bucket. What should trigger the Lambda function in this scenario?
Explanation: The preferred approach is for the function to run automatically upon the creation of new files. Manual triggers would not support automation. Deletion events apply to object removals, not uploads. Scheduled timers may not catch uploads in real-time and are less efficient for this use case.
Which practice helps improve the security of Lambda functions integrated with storage buckets?
Explanation: Applying the principle of least privilege limits risks by granting just the permissions needed. Sharing access keys between functions is insecure and makes auditing difficult. Disabling encryption and allowing public write access both reduce data security and increase vulnerability to unauthorized actions.
Why is it important to set an appropriate timeout for Lambda functions triggered by storage bucket events?
Explanation: If the function times out during processing, the job may be incomplete and might lead to unintended repeated executions or wasted resources. Bucket size cannot be modified by function timeouts. Timeouts do not directly affect upload speeds, nor do they control user access.
How can you monitor and debug failed Lambda executions triggered by storage bucket events?
Explanation: Reviewing logs is the standard method to monitor and troubleshoot failed executions, as logs capture error details and stack traces. Increasing versioning on storage does not provide execution logs. Disabling tracing removes valuable debugging information. Deleting the function role will halt further executions but won't provide diagnostics.
Which feature allows you to invoke Lambda functions only for specific object key patterns or file types when objects are added to a bucket?
Explanation: Event notification filters enable you to process only files matching defined prefixes or suffixes, such as certain file types. Logging settings only record actions but do not trigger functions. Public access blocks and access control lists control access, not invocation logic based on file patterns.