Ecng.Backup.Azure 1.0.47

Ecng.Backup.Azure

Azure Blob Storage backup provider implementing IBackupService.

Overview

AzureBlobService provides cloud backup capabilities using Microsoft Azure Blob Storage. It uses block blobs with chunked uploads for reliable large file transfers.

Usage

Creating the Service

using Ecng.Backup;
using Ecng.Backup.Azure;

var azure = new AzureBlobService(
    connectionString: "DefaultEndpointsProtocol=https;AccountName=myaccount;AccountKey=...;EndpointSuffix=core.windows.net",
    container: "my-backup-container"
);

// Container is created automatically if it doesn't exist

Features

Uploading Files

var entry = new BackupEntry { Name = "backups/database/2024-01-15.bak" };

await using var stream = File.OpenRead(@"C:\backups\database.bak");
await azure.UploadAsync(entry, stream, progress =>
{
    Console.WriteLine($"Upload: {progress}%");
});
// Uses 4MB block chunks for reliable uploads

Downloading Files

var entry = new BackupEntry { Name = "backups/database/2024-01-15.bak" };

await using var stream = File.Create(@"C:\restore\database.bak");
await azure.DownloadAsync(entry, stream, null, null, progress =>
{
    Console.WriteLine($"Download: {progress}%");
});

Partial Download (Resume Support)

var entry = new BackupEntry { Name = "large-file.zip" };

// Get total size
await azure.FillInfoAsync(entry);

// Download specific range
long offset = 1024 * 1024 * 100; // Start at 100MB
long length = 1024 * 1024 * 50;  // Download 50MB

await using var stream = new MemoryStream();
await azure.DownloadAsync(entry, stream, offset, length, p => { });

Listing Blobs

// List all blobs with prefix
var folder = new BackupEntry { Name = "backups/2024" };

await foreach (var blob in azure.FindAsync(folder, criteria: null))
{
    Console.WriteLine($"{blob.GetFullPath()}: {blob.Size} bytes");
    Console.WriteLine($"  Last modified: {blob.LastModified}");
}

// Search with filter
await foreach (var blob in azure.FindAsync(null, criteria: ".bak"))
{
    Console.WriteLine(blob.Name);
}

Deleting Blobs

var entry = new BackupEntry { Name = "backups/old-backup.zip" };
await azure.DeleteAsync(entry);

Getting Blob Info

var entry = new BackupEntry { Name = "backups/data.zip" };
await azure.FillInfoAsync(entry);

Console.WriteLine($"Size: {entry.Size}");
Console.WriteLine($"Modified: {entry.LastModified}");

Connection String

Get your connection string from Azure Portal:

1. Go to your Storage Account
2. Select "Access keys" under Security + networking
3. Copy the "Connection string"

Example format:

DefaultEndpointsProtocol=https;AccountName=mystorageaccount;AccountKey=abc123...==;EndpointSuffix=core.windows.net

NuGet

Install-Package Ecng.Backup.Azure

Dependencies

• Azure.Storage.Blobs
• Ecng.Backup