async request(verb, requestUrl, data, headers) {
        if (this._disposed) {
            throw new Error('Client has already been disposed.');
        }
        let parsedUrl = new URL(requestUrl);
        let info = this._prepareRequest(verb, parsedUrl, headers);
        // Only perform retries on reads since writes may not be idempotent.
        let maxTries = this._allowRetries && RetryableHttpVerbs.indexOf(verb) != -1
            ? this._maxRetries + 1
            : 1;
        let numTries = 0;
        let response;
        while (numTries < maxTries) {
            response = await this.requestRaw(info, data);
            // Check if it's an authentication challenge
            if (response &&
                response.message &&
                response.message.statusCode === HttpCodes.Unauthorized) {
                let authenticationHandler;
                for (let i = 0; i < this.handlers.length; i++) {
                    if (this.handlers[i].canHandleAuthentication(response)) {
                        authenticationHandler = this.handlers[i];
                        break;
                    }
                }
                if (authenticationHandler) {
                    return authenticationHandler.handleAuthentication(this, info, data);
                }
                else {
                    // We have received an unauthorized response but have no handlers to handle it.
                    // Let the response return to the caller.
                    return response;
                }
            }
            let redirectsRemaining = this._maxRedirects;
            while (HttpRedirectCodes.indexOf(response.message.statusCode) != -1 &&
                this._allowRedirects &&
                redirectsRemaining > 0) {
                const redirectUrl = response.message.headers['location'];
                if (!redirectUrl) {
                    // if there's no location to redirect to, we won't
                    break;
                }
                let parsedRedirectUrl = new URL(redirectUrl);
                if (parsedUrl.protocol == 'https:' &&
                    parsedUrl.protocol != parsedRedirectUrl.protocol &&
                    !this._allowRedirectDowngrade) {
                    throw new Error('Redirect from HTTPS to HTTP protocol. This downgrade is not allowed for security reasons. If you want to allow this behavior, set the allowRedirectDowngrade option to true.');
                }
                // we need to finish reading the response before reassigning response
                // which will leak the open socket.
                await response.readBody();
                // strip authorization header if redirected to a different hostname
                if (parsedRedirectUrl.hostname !== parsedUrl.hostname) {
                    for (let header in headers) {
                        // header names are case insensitive
                        if (header.toLowerCase() === 'authorization') {
                            delete headers[header];
                        }
                    }
                }
                // let's make the request with the new redirectUrl
                info = this._prepareRequest(verb, parsedRedirectUrl, headers);
                response = await this.requestRaw(info, data);
                redirectsRemaining--;
            }
            if (HttpResponseRetryCodes.indexOf(response.message.statusCode) == -1) {
                // If not a retry code, return immediately instead of retrying
                return response;
            }
            numTries += 1;
            if (numTries < maxTries) {
                await response.readBody();
                await this._performExponentialBackoff(numTries);
            }
        }
        return response;
    }
Makes a raw http request.
All other methods such as get, post, patch, and request ultimately call this.
Prefer get, del, post and patch