S3 Object Lambda - Data Engineering on AWS

What is S3 Object Lambda?

S3 Object Lambda allows you to add your own code to process data retrieved from S3 before it is returned to an application, enabling dynamic data transformations and customizations.

Key Concepts

• Transformation: Modify the data on-the-fly as it is retrieved.
• Lambda Function: Execute custom code via AWS Lambda to process the data.
• Access Point: Use S3 Access Points to simplify access to S3 buckets.

How to Set Up S3 Object Lambda

1. Create an S3 bucket or use an existing one.
2. Write a Lambda function that processes the data. Example:

exports.handler = async (event) => {
                    const response = event.Records[0].cf.response;
                    // Example: Convert body to uppercase
                    response.body = response.body.toUpperCase();
                    return response;
                };

3. Create an S3 Object Lambda Access Point using the AWS Management Console or CLI.
4. Configure the Access Point to associate it with your Lambda function.
5. Test the setup by retrieving data through the Access Point.

Best Practices

• Keep Lambda functions lightweight to reduce latency.
• Implement error handling in your Lambda function.
• Monitor and log Lambda function performance using Amazon CloudWatch.

Flowchart: S3 Object Lambda Workflow

graph TD;
            A[Start] --> B[Retrieve Object from S3];
            B --> C{Does Object Exist?};
            C -- Yes --> D[Invoke Lambda Function];
            C -- No --> E[Return Error];
            D --> F[Process Data];
            F --> G[Return Processed Data];
            E --> H[End];
            G --> H;
        

FAQ