AWS Lambda Tutorial

Serverless funkce na AWS. Triggery, cold start, layers a best practices.

Základní Lambda

// handler.js
exports.handler = async (event) => {
    const { name } = JSON.parse(event.body);
    return {
        statusCode: 200,
        headers: { 'Content-Type': 'application/json' },
        body: JSON.stringify({ message: \`Hello \${name}\` })
    };
};

Triggery

• API Gateway — HTTP endpoints
• S3 — file upload events
• SQS — queue processing
• EventBridge — cron/schedule
• DynamoDB Streams — change data capture

Cold Start mitigace

• Provisioned Concurrency (platí se)
• SnapStart (Java)
• Menší deployment package
• Warm-up pings (CloudWatch Events)

Shrnutí

Lambda je ideální pro event-driven, short-lived workloady. Pozor na cold start a vendor lock-in.