// </Snippet_DownloadFromDirectory>
#endregion
#region Download a binary file from a directory
// ---------------------------------------------------------
// Download file from directory (binary)
//----------------------------------------------------------
// <Snippet_DownloadBinaryFromDirectory>
public async Task DownloadFile(DataLakeFileSystemClient fileSystemClient)
{
DataLakeDirectoryClient directoryClient =
fileSystemClient.GetDirectoryClient("my-directory");
DataLakeFileClient fileClient =
directoryClient.GetFileClient("my-image.png");
Response <FileDownloadInfo> downloadResponse = await fileClient.ReadAsync();
BinaryReader reader = new BinaryReader(downloadResponse.Value.Content);
FileStream fileStream =
File.OpenWrite("C:\\Users\\contoso\\my-image-downloaded.png");
int bufferSize = 4096;
byte[] buffer = new byte[bufferSize];
int count;
while ((count = reader.Read(buffer, 0, buffer.Length)) != 0)
{
fileStream.Write(buffer, 0, count);
}
await fileStream.FlushAsync();
fileStream.Close();
}
public async Task ReadAsync()
{
// Create a temporary Lorem Ipsum file on disk that we can upload
string originalPath = CreateTempFile(SampleFileContent);
// Get a temporary path on disk where we can download the file
string downloadPath = CreateTempPath();
// Make StorageSharedKeyCredential to pass to the serviceClient
string storageAccountName = StorageAccountName;
string storageAccountKey = StorageAccountKey;
Uri serviceUri = StorageAccountBlobUri;
StorageSharedKeyCredential sharedKeyCredential = new StorageSharedKeyCredential(storageAccountName, storageAccountKey);
// Create DataLakeServiceClient using StorageSharedKeyCredentials
DataLakeServiceClient serviceClient = new DataLakeServiceClient(serviceUri, sharedKeyCredential);
// Get a reference to a filesystem named "sample-filesystem-readasync" and then create it
DataLakeFileSystemClient filesystem = serviceClient.GetFileSystemClient(Randomize("sample-filesystem-read"));
await filesystem.CreateAsync();
try
{
// Get a reference to a file named "sample-file" in a filesystem
DataLakeFileClient file = filesystem.GetFileClient(Randomize("sample-file"));
// First upload something the DataLake file so we have something to download
await file.CreateAsync();
await file.AppendAsync(File.OpenRead(originalPath), 0);
await file.FlushAsync(SampleFileContent.Length);
// Download the DataLake file's contents and save it to a file
Response <FileDownloadInfo> fileContents = await file.ReadAsync();
using (FileStream stream = File.OpenWrite(downloadPath))
{
fileContents.Value.Content.CopyTo(stream);
}
// Verify the contents
Assert.AreEqual(SampleFileContent, File.ReadAllText(downloadPath));
}
finally
{
// Clean up after the test when we're finished
await filesystem.DeleteAsync();
}
}
public async Task <byte[]> Read(string path, CancellationToken token)
{
path.VerifyNotEmpty(nameof(path));
DataLakeFileClient file = _fileSystem.GetFileClient(path);
Response <FileDownloadInfo> response = await file.ReadAsync(token);
_logger.LogTrace($"{nameof(Read)} from {path}");
using MemoryStream memory = new MemoryStream();
await response.Value.Content.CopyToAsync(memory);
return(memory.ToArray());
}
public async Task <dynamic> DownloadJsonData(DataLakeFileSystemClient fileSystemClient, string directory, string filePath)
{
DataLakeDirectoryClient directoryClient =
fileSystemClient.GetDirectoryClient(directory);
DataLakeFileClient fileClient =
directoryClient.GetFileClient(filePath);
Response <FileDownloadInfo> downloadResponse = await fileClient.ReadAsync();
var streamContent = new StreamContent(downloadResponse.Value.Content);
var stringContent = await streamContent.ReadAsStringAsync();
return(JsonConvert.DeserializeObject <dynamic>(stringContent));
}
public async Task <(byte[]? Data, ETag?Etag)> ReadWithTag(string path, CancellationToken token = default)
{
path = WithBasePath(path);
_logger.LogTrace($"Reading {path}");
try
{
DataLakeFileClient file = _fileSystem.GetFileClient(path);
Response <FileDownloadInfo> response = await file.ReadAsync(token);
using MemoryStream memory = new MemoryStream();
await response.Value.Content.CopyToAsync(memory);
return(memory.ToArray(), response.Value.Properties.ETag);
}
catch (RequestFailedException ex) when(ex.ErrorCode == "BlobNotFound")
{
return(null, null);
}
}
// </Snippet_UploadFileBulk>
#endregion
#region Download a file from a directory
// ---------------------------------------------------------
// Download file from directory
//----------------------------------------------------------
// <Snippet_DownloadFromDirectory>
public async Task DownloadFile2(DataLakeFileSystemClient fileSystemClient)
{
DataLakeDirectoryClient directoryClient =
fileSystemClient.GetDirectoryClient("my-directory");
DataLakeFileClient fileClient = directoryClient.GetFileClient("my-image.png");
Response <FileDownloadInfo> downloadResponse = await fileClient.ReadAsync();
StreamReader reader = new StreamReader(downloadResponse.Value.Content);
FileStream fileStream = File.OpenWrite("C:\\Users\\contoso\\my-image-downloaded.png");
string output = await reader.ReadToEndAsync();
byte[] data = System.Text.Encoding.UTF8.GetBytes(output);
fileStream.Write(data, 0, data.Length);
await fileStream.FlushAsync();
fileStream.Close();
}
public async Task DownloadFile(DataLakeFileSystemClient fileSystemClient, string keywordFilename, string outputFilePath)
{
DataLakeDirectoryClient directoryClient = fileSystemClient.GetDirectoryClient(stAccountDirectory);
DataLakeFileClient fileClient = directoryClient.GetFileClient(keywordFilename);
Response <FileDownloadInfo> downloadResponse = await fileClient.ReadAsync();
BinaryReader reader = new BinaryReader(downloadResponse.Value.Content);
FileStream fileStream = File.OpenWrite(outputFilePath);
int bufferSize = 4096;
byte[] buffer = new byte[bufferSize];
int count;
while ((count = reader.Read(buffer, 0, buffer.Length)) != 0)
{
fileStream.Write(buffer, 0, count);
}
await fileStream.FlushAsync();
fileStream.Close();
}
private static async Task DownloadAsync(string fileSystem, string directory, string fileName)
{
DataLakeFileSystemClient fileSystemClient = _dataLakeClient.GetFileSystemClient(fileSystem);
DataLakeDirectoryClient directoryClient =
fileSystemClient.GetDirectoryClient(directory);
DataLakeFileClient fileClient =
directoryClient.GetFileClient(fileName);
Console.WriteLine("\nStarting download...");
Response <FileDownloadInfo> downloadResponse = await fileClient.ReadAsync();
var reader = new BinaryReader(downloadResponse.Value.Content);
FileStream fileStream =
File.OpenWrite($"{fileName}");
const int bufferSize = 4096;
var buffer = new byte[bufferSize];
int count;
while ((count = reader.Read(buffer, 0, buffer.Length)) != 0)
{
fileStream.Write(buffer, 0, count);
}
await fileStream.FlushAsync();
fileStream.Close();
Console.WriteLine($"File downloaded to {fileName}\n");
}