connect.ts

// This is a sample of what the event object that gets
// passed to your connect route could look like.
// I've chosen to use an authorizer that will pass 
// the userId so that I can store the connectionId with the userId
// in my database

interface APIGatewayWebsocketEvent {
  methodArn: string;
  queryStringParameters: {
    token: string;
  };
  requestContext: {
    eventType: string;
    connectionId: string;
    authorizer: {
      userId: string;
    };
  };
}

function onConnect(event: APIGatewayWebsocketEvent) {
  const {
    requestContext: {
      connectionId,
      authorizer: { userId },
    },
  } = event;
  // save connectionId & userId to database for further
  // messaging capabilities
}