Microsoft.Research.DataOnboarding.RepositoryAdapters.SkyDrive.SkyDriveAdapter.DownloadFile C# (CSharp) Method

        public DataFile DownloadFile(string downloadUrl, string authorization, string fileName)
        {
            DataFile dataFile = new DataFile();

            AuthToken token = new AuthToken()
            {
                AccessToken = authorization
            };

            dataFile.FileContent = this.DownloadFile(downloadUrl, token);
            string extension = Path.GetExtension(fileName);

            if (extension.ToUpperInvariant().Equals(Constants.XLSX, StringComparison.OrdinalIgnoreCase))
            {
                dataFile.FileExtentsion = extension;
            }
            else
            {
                dataFile.FileExtentsion = ".zip";
            }

            dataFile.FileName = string.Format("{0}{1}", Path.GetFileNameWithoutExtension(fileName), dataFile.FileExtentsion);
            return dataFile;
        }

        public void DownloadFile_ShouldReturnNull_WhenThereIsAnExceptionWhileDownloadingFile()
        {
            SkyDriveAdapter skyDriveAdapter = new SkyDriveAdapter();
            DataFile dataFile = null;
            string errorMessage = "Some error message";

            try
            {
                using (ShimsContext.Create())
                {
                    ShimSkyDriveAdapter.AllInstances.DownloadFileStringAuthToken = (sda, fileId, authToken) => { throw new Exception(errorMessage); return new byte[0]; };
                    ShimDiagnosticsProvider.AllInstances.WriteErrorTraceTraceEventIdException = (diagnosticsProvider, traceEventId, message) => { };
                    dataFile = skyDriveAdapter.DownloadFile("DownloadUrl", "Authorization", "SomeFileName.xlsx");
                }
            }
            catch (Exception ex)
            {
                Assert.IsNull(dataFile);
                Assert.AreEqual(errorMessage, ex.Message.ToString());
            }
        }