CDK Constructs

CDK Constructs encapsulate Arda’s engineering best practices for individual AWS resource groups. They are high-level (L2/L3) constructs that compose L1 and L2 AWS resources with pre-configured defaults, naming conventions, and security settings. Defined in src/cdk/constructs/.

Standard Construct Pattern

Each construct module defines:

Type	Description
Configuration	True configuration parameters affecting resource behavior
Props extends Configuration	Adds CDK binding types (e.g., ec2.IVpc) for context dependencies. All members readonly
Built	Resources and values produced by the construct. All members readonly

Constructor signature:

constructor(scope: cdk.Construct, id: string, props: Props)

Public member: readonly build: Built

Best practice: include static validateProps(id: string, props: Props): boolean to throw before super() if inputs are invalid.

Construct Template

import * as cdk from 'aws-cdk-lib';
import { Construct } from 'constructs';

export interface Configuration { /* behavioral params */ }
export interface Props extends Configuration { /* CDK binding types */ }
export interface Built { /* produced resources */ }

export class MyConstruct extends Construct {
  public readonly build: Built;

  static validateProps(id: string, props: Props): boolean { /* validate */ return true; }

  constructor(scope: cdk.Construct, id: string, props: Props) {
    validateProps(id, props);
    super(scope, id);
    // define resources...
    this.build = { /* results */ };
  }
}

Organization by Category

Category	Contents
compute	Lambda functions, EKS clusters
networking	VPCs, Load Balancers
storage	S3 buckets, EFS, DynamoDB, RDS
xgress	API Gateway, VPC Links, DNS entries
oam	CloudWatch, X-Ray, monitoring dashboards
platform	Global Arda Platform configuration constructs

An inline-lambdas/ subdirectory holds Lambda function source code that is read as text by CDK constructs (enabling full IDE support — type checking, linting — for Lambda code that would otherwise be embedded as strings).

Reuse Across Repositories

Constructs are currently hosted in the infrastructure repository. The long-term plan is to publish them as npm packages so component repositories can consume them directly without duplication. Until then, some component repositories may temporarily copy reusable construct code.