CDK Websocket Domain Name example

cdk-websocket-with-domain.ts

import * as path from 'path';
import * as apigatewayv2 from '@aws-cdk/aws-apigatewayv2';
import * as apigatewayv2Integrations from '@aws-cdk/aws-apigatewayv2-integrations';
import * as certificatemanager from '@aws-cdk/aws-certificatemanager';
import * as lnjs from '@aws-cdk/aws-lambda-nodejs';
import * as route53 from '@aws-cdk/aws-route53';
import * as alias from '@aws-cdk/aws-route53-targets';
import * as cdk from '@aws-cdk/core';

export interface WebsocketExampleProps {
  wssDomainName: string;
  certificate: certificatemanager.ICertificate;
  zone: route53.IHostedZone;
}

export class WebsocketExample extends cdk.Construct {
  constructor(
    scope: cdk.Construct,
    id: string,
    { wssDomainName, certificate, zone }: WebsocketExampleProps,
  ) {
    super(scope, id);

    const connectHandler = new lnjs.NodejsFunction(this, 'ConnectHandler', {
      entry: path.join(__dirname, './connect-handler.ts'),
    });
    const disconnectHandler = new lnjs.NodejsFunction(
      this,
      'DisconnectHandler',
      {
        entry: path.join(__dirname, './disconnect-handler.ts'),
      },
    );
    const defaultHandler = new lnjs.NodejsFunction(this, 'DefaultHandler', {
      entry: path.join(__dirname, './default-handler.ts'),
    });

    const webSocketApi = new apigatewayv2.WebSocketApi(this, 'WebsocketExample', {
      connectRouteOptions: {
        integration: new apigatewayv2Integrations.LambdaWebSocketIntegration({
          handler: connectHandler,
        }),
      },
      disconnectRouteOptions: {
        integration: new apigatewayv2Integrations.LambdaWebSocketIntegration({
          handler: disconnectHandler,
        }),
      },
      defaultRouteOptions: {
        integration: new apigatewayv2Integrations.LambdaWebSocketIntegration({
          handler: defaultHandler,
        }),
      },
    });

    const stageName = 'prod';

    const stage = new apigatewayv2.WebSocketStage(this, 'WssStage', {
      webSocketApi,
      stageName,
      autoDeploy: true,
    });

    const domainName = new apigatewayv2.DomainName(this, 'WssDomain', {
      certificate,
      domainName: wssDomainName,
    });

    const apiMapping = new apigatewayv2.ApiMapping(this, 'ApiMapping', {
      api: webSocketApi,
      domainName: domainName,
      stage,
    });

    apiMapping.node.addDependency(domainName);

    new route53.ARecord(this, 'WssAGW', {
      recordName: wssDomainName,
      zone,
      target: route53.RecordTarget.fromAlias(
        new alias.ApiGatewayv2DomainProperties(
          domainName.regionalDomainName,
          domainName.regionalHostedZoneId,
        ),
      ),
    });
  }
}