AWS Lambda -- Portfolio Projects
Project 1: REST API with Lambda + API Gateway + DynamoDB
Level: Beginner | Time: 1-2 days | GitHub: aws-serverless-api
Serverless CRUD API -- no servers, automatic scaling, pay per request.
python
import boto3, json
dynamodb = boto3.resource("dynamodb")
table = dynamodb.Table("Items")
def lambda_handler(event, context):
method = event["httpMethod"]
path = event["path"]
if method == "GET" and path == "/items":
result = table.scan()
return {"statusCode": 200, "body": json.dumps(result["Items"])}
if method == "POST" and path == "/items":
body = json.loads(event["body"])
table.put_item(Item=body)
return {"statusCode": 201, "body": json.dumps(body)}
return {"statusCode": 404, "body": "Not Found"}
hcl
resource "aws_lambda_function" "api" {
filename = "function.zip"
function_name = "items-api"
runtime = "python3.12"
handler = "handler.lambda_handler"
role = aws_iam_role.lambda.arn
memory_size = 256
timeout = 30
}
Steps: Lambda + API Gateway + DynamoDB via Terraform, test with curl, add x-ray tracing
Project 2: Event-Driven Processing with SQS
Level: Intermediate | Time: 2 days | GitHub: aws-lambda-event-driven
Lambda processes SQS messages with batching, dead-letter queue, and retry logic.
python
def lambda_handler(event, context):
success, failed = [], []
for record in event["Records"]:
try:
msg = json.loads(record["body"])
process_message(msg)
success.append(record["messageId"])
except Exception as e:
print(f"Failed {record['messageId']}: {e}")
failed.append({"itemIdentifier": record["messageId"]})
return {"batchItemFailures": failed} # Partial batch failure reporting
Steps: SQS + Lambda trigger, DLQ for failed messages, CloudWatch alarm on DLQ depth
Portfolio Checklist
•[ ] Lambda in VPC with private subnet (for RDS/ElasticCache access)
•[ ] IAM role with minimum necessary permissions
•[ ] X-Ray tracing enabled
•[ ] Reserved concurrency set (prevent runaway scaling)
•[ ] CloudWatch alarm: error rate > 1%
