/// <summary>
/// Gets the download <see cref="Uri"/> for the specified file as an asynchronous operation.
/// </summary>
/// <param name="value">The <see cref="IMetadataApi"/> to get the download URI.</param>
/// <param name="fileName">The name of the file to download.</param>
/// <param name="fileHash">The hash of the file to download.</param>
/// <returns>
/// A <see cref="Task{T}"/> containing the <see cref="Uri"/> to download the file specified by
/// <paramref name="fileName"/> and <paramref name="fileHash"/> from as an asynchronous operation.
/// </returns>
/// <exception cref="ArgumentNullException">
/// <paramref name="value"/> is <see langword="null"/>.
/// </exception>
public static async Task <Uri> GetDownloadUriAsync(this IMetadataApi value, string fileName, string fileHash)
{
if (value == null)
{
throw new ArgumentNullException("value");
}
return(await value.GetDownloadUriAsync(fileName, fileHash, null, null));
}
public static async Task IMetadataApiExtensions_GetDownloadUriAsync_Throws_If_Value_Is_Null()
{
// Arrange
IMetadataApi value = null;
string fileName = "MyFileName.dts";
string fileHash = "58b653e3762e8048995e00024a512c53";
// Act and Assert
await Assert.ThrowsAsync <ArgumentNullException>("value", () => value.GetDownloadUriAsync(fileName, fileHash));
}
public static async Task IMetadataApiExtensions_GetDownloadUriAsync_Calls_Interface_Method_With_No_File_Range()
{
// Arrange
string fileName = "MyFileName.dts";
string fileHash = "58b653e3762e8048995e00024a512c53";
Uri uri = new Uri("https://dn.updates.qas.com/MyFile.dts");
Mock <IMetadataApi> mock = new Mock <IMetadataApi>();
mock.Setup((p) => p.GetDownloadUriAsync(fileName, fileHash, null, null))
.ReturnsAsync(uri)
.Verifiable();
IMetadataApi value = mock.Object;
// Act and Assert
Uri result = await value.GetDownloadUriAsync(fileName, fileHash);
mock.Verify();
Assert.Same(uri, result);
}
/// <summary>
/// Downloads the specified file from the specified package group as an asynchronous operation.
/// </summary>
/// <param name="service">The Metadata API to use to get the download URI.</param>
/// <param name="fileStore">The file store to register the download with if successfully downloaded.</param>
/// <param name="group">The package group to download the file from.</param>
/// <param name="file">The data file to download.</param>
/// <param name="downloadRootPath">The root path to download data to.</param>
/// <param name="verifyDownloads">Whether to verify file downloads.</param>
/// <param name="cancellationToken">The cancellation token to use to cancel any downloads.</param>
/// <returns>
/// A <see cref="Task"/> representing the asynchronous operation.
/// </returns>
private static async Task DownloadFileAsync(
IMetadataApi service,
IFileStore fileStore,
PackageGroup group,
DataFile file,
string downloadRootPath,
bool verifyDownloads,
CancellationToken cancellationToken)
{
if (cancellationToken.IsCancellationRequested)
{
return;
}
Console.WriteLine("File name: {0}", file.FileName);
Console.WriteLine("File hash: {0}", file.MD5Hash);
Console.WriteLine("File size: {0:N0}", file.Size);
// Query the URIs to download the file from
Uri uri = await service.GetDownloadUriAsync(file.FileName, file.MD5Hash);
if (uri == null)
{
Console.WriteLine("File '{0}' is not available for download at this time.", file.FileName);
Console.WriteLine();
return;
}
Console.WriteLine("File URI: {0}", uri);
Console.WriteLine();
// Create the path to the directory to download the file to
string directoryPath = Path.Combine(
downloadRootPath,
group.PackageGroupCode,
group.Vintage);
string filePath = Path.GetFullPath(Path.Combine(directoryPath, file.FileName));
// Create the directory if it doesn't already exist
if (!Directory.Exists(directoryPath))
{
Directory.CreateDirectory(directoryPath);
}
// Download the file
Console.WriteLine("Downloading '{0}' ({1}) to '{2}'...", file.FileName, file.MD5Hash, filePath);
using (HttpClient client = new HttpClient())
{
using (HttpResponseMessage response = await client.GetAsync(uri, cancellationToken))
{
response.EnsureSuccessStatusCode();
using (Stream stream = await response.Content.ReadAsStreamAsync())
{
using (Stream fileStream = File.Open(filePath, FileMode.OpenOrCreate, FileAccess.ReadWrite, FileShare.None))
{
// Ensure any existing file is overwritten
fileStream.SetLength(0L);
await stream.CopyToAsync(fileStream, 4096, cancellationToken);
}
}
}
}
// Validate the download is correct, if configured.
// Don't register the file in the file store as the file download became corrupted somehow.
if (!verifyDownloads || VerifyDownload(filePath, file.MD5Hash))
{
// Register the file with the file store so further invocations
// of the application don't unnecessarily download the file again
fileStore.RegisterFile(file.MD5Hash, filePath);
}
}
