Refactor x-ray usage

[doriansmiley]

Refactor the AbstractController.register function to properly use XRay. Should look like this:

// you can override invoke in a subclass to adjust the return type
    protected async invoke(event): Promise<any> {
        return new Promise<any>((resolve, reject)=>{
            // add X-Ray telemetry passing the subsegment
            AWSXRay.captureAsyncFunc(this.getSegmentName(), async (subsegment) => {
                try {
                    const result = await this.processRequest(event);
                    resolve(result);
                } catch(e) {
                    this.log(LogLevels.ERROR, e.message, event, e);
                    reject(e);
                } finally {
                    subsegment.close();
                }

            });
        });
    }

    protected async processRequest(event): Promise<any> {
        // to open a subsegment for x-ray call AWSXRay.captureAsyncFunc
        // you'll have to promisfy the call or wrap in a promise like invoke
        // log request received
        this.log(LogLevels.INFO, this.getSegmentName() + ' Request received', event);
        try {
            // first validate the incoming request.
            this.checkValidation(event);

            // stub for override
            // in your sub classes you should supply value for result and error
            return null;
        } catch (e) {
            // log error response
            this.log(LogLevels.ERROR, e.message, null, e);
            throw e;
        }
    }

In index.ts make sure we are opening up the main segment and closing it as follows

var AWSXRay = require('aws-xray-sdk');

app.use(AWSXRay.express.openSegment('defaultName'));  // required at the start of your routes

app.get('/', function (req, res) {
  res.render('index');
});

app.use(AWSXRay.express.closeSegment()); //Required at the end of your routes / first in error handling routes

Reference is at: https://docs.aws.amazon.com/xray-sdk-for-nodejs/latest/reference/