`
            this.server = sinon.fakeServer.create();
    this.server.autoRespond = true;
    sinon.FakeXMLHttpRequest.useFilters = true;

          sinon.FakeXMLHttpRequest.addFilter(function (method, url, async, username, password) {
        // Don't fake json file read requests
        if (url == inputUrl) {
            return true;
        }
    });

    this.resultfile = this.readJsonFile(inputUrl);

    this.server.respondWith("GET", endUrl,
                   [200, { "Content-Type": "application/json" }, this.resultfile]);

    console.log (this.server.requests); // Logs all requests so far`