Cdk Patterns

Examples

Example 1: Serverless API Pattern

import { Construct } from "constructs";
import * as apigateway from "aws-cdk-lib/aws-apigateway";
import * as lambda from "aws-cdk-lib/aws-lambda";
import * as dynamodb from "aws-cdk-lib/aws-dynamodb";

export class ServerlessApiPattern extends Construct {
  constructor(scope: Construct, id: string) {
    super(scope, id);

    const table = new dynamodb.Table(this, "Table", {
      partitionKey: { name: "pk", type: dynamodb.AttributeType.STRING },
      billingMode: dynamodb.BillingMode.PAY_PER_REQUEST,
      removalPolicy: cdk.RemovalPolicy.RETAIN,
    });

    const handler = new lambda.Function(this, "Handler", {
      runtime: lambda.Runtime.NODEJS_20_X,
      handler: "index.handler",
      code: lambda.Code.fromAsset("lambda"),
      environment: { TABLE_NAME: table.tableName },
      tracing: lambda.Tracing.ACTIVE,
    });

    table.grantReadWriteData(handler);

    new apigateway.LambdaRestApi(this, "Api", { handler });
  }
}

Best Practices

• ✅ Do: Use cdk.Tags.of(this).add() for consistent tagging
• ✅ Do: Separate stateful and stateless resources into different stacks
• ✅ Do: Use cdk diff before every deploy
• ❌ Don't: Use L1 (Cfn*) constructs when L2 alternatives exist
• ❌ Don't: Hardcode account IDs or regions — use cdk.Aws.ACCOUNT_ID

Troubleshooting

Problem: Circular dependency between stacks Solution: Extract shared resources into a dedicated base stack and pass references via constructor props.

Limitations

• Use this skill only when the task clearly matches the scope described above.
• Do not treat the output as a substitute for environment-specific validation, testing, or expert review.
• Stop and ask for clarification if required inputs, permissions, safety boundaries, or success criteria are missing.