Lyo.Sftp.Client 1.0.9

Lyo.Sftp.Client

SFTP wrapper over SSH.NET for Lyo hosts and storage adapters (Lyo.IO.Temp.Sftp, Lyo.FileStorage.Sftp). Hosts should call *Async (Task + CancellationToken). Those methods use SSH.NET's async API and await-safe pool/per-client gates. Sync methods block on the async path. The client leases pooled connections, jails POSIX paths under RootRemoteDirectory via Lyo.Common.Pathing.PathHelpers, checks host-key allow lists, and accepts password or private-key auth. It logs through ILogger and records sftp.* metrics. Concurrent callers are fine up to MaxPooledClients. Do not share one leased Stream across threads.

Features

• Async. Prefer *Async from hosts and adapters. Sync wrappers block on the async implementation. No Task.Run.
• Pooled leases. MaxPooledClients concurrent SSH.NET clients. A per-client SemaphoreSlim serializes ops across awaits.
• Concurrent callers. The pool caps parallelism. One leased stream is not safe across threads.
• Path jail. Paths resolve under RootRemoteDirectory with PathStyle.Posix.
• Auth. Password and/or PEM or key-file private key. Host-key fingerprint allow list, or AcceptAny for tests.
• Logging and metrics. ILogger plus IMetrics (sftp.connect, sftp.operation, sftp.bytes, sftp.pool, sftp.errors). EnableMetrics opt-out uses NullMetrics.
• DI. AddSftpClient / AddSftpClientFromConfiguration.

Examples

Registration

services.AddSftpClient(o =>
{
    o.Host = "sftp.example.com";
    o.Username = "lyo";
    o.Password = secret;
    o.RootRemoteDirectory = "/data/lyo";
    o.HostKeyPolicy = SftpHostKeyPolicy.FingerprintAllowList;
    o.AllowedHostKeyFingerprints.Add("SHA256:...");
});

Async upload / download

await client.UploadAsync("report.bin", bytes, ct);
var copy = await client.DownloadBytesAsync("report.bin", ct);

Dependencies

Generated from ProjectReference / PackageReference (same model as docs/Lyo.ProjectGraph.html).

• Lyo.Common (direct, lyo)
• Lyo.Exceptions (direct, lyo)
• Lyo.Metrics (direct, lyo)
• Microsoft.Extensions.Configuration.Binder 10.0.5 (direct, microsoft)
• Microsoft.Extensions.DependencyInjection.Abstractions 10.0.5 (direct, microsoft)
• Microsoft.Extensions.Logging.Abstractions 10.0.5 (direct, microsoft)
• SSH.NET 2025.1.0 (direct, third-party)
• Microsoft.Extensions.Options.ConfigurationExtensions 10.0.5 (transitive, microsoft)
• System.Memory 4.6.3 (transitive, microsoft, netstandard2.0)
• System.Text.Json 10.0.5 (transitive, microsoft, netstandard2.0)