Configuring API Gateway with CDK

Applicable when

• API Gateway is used to support client API calls
• The expected number of resources is not huge (<60 resources)

Non-applicable when

• A large number of resources is expected (You will need to split stacks in that case)

Implementation

The code below will create a new nested stack with configured API Gateway and utility method to easily add new resources

import { MethodLoggingLevel, Resource, RestApi } from '@aws-cdk/aws-apigateway';
import { NestedStack, NestedStackProps } from '@aws-cdk/aws-cloudformation';
import { Construct } from '@aws-cdk/core';
import { withEnv } from '../util/consts';

export class RestApiStack extends NestedStack {
  public api: RestApi;
  public deployment: Deployment;

  constructor(scope: Construct, id: string, props?: NestedStackProps) {
    super(scope, id, props);

    this.api = new RestApi(this, withEnv('rest-api'), {
      deployOptions: {
        loggingLevel: MethodLoggingLevel.ERROR,
      },
    });
  }

  public getResource(path: string): Resource {
    const parts = path.split('/');
    let currentNode = this.api.root;

    for (const part of parts) {
      currentNode = currentNode.getResource(part) ?? currentNode.addResource(part);
    }

    return currentNode as Resource;
  }
}

Usage example

export class BackendStack extends Stack {
  constructor(scope: App, id: string, props?: StackProps) {
    super(scope, id, props);

    const restAPI = new RestApiStack(this, withEnv('rest-api-stack'));
    ...
    restAPI
      .getResource('servers/{serverId}/users/{username}/config')
      .addMethod('GET', new LambdaIntegration(lambdaFunction, { proxy: true }));
  }
}