docs/sdk/rust/ssh.mdx
Reach a running sandbox over SSH: open a native in-process SSH client, run exec requests, attach an interactive shell, transfer files over SFTP, or stand up a reusable SSH server endpoint. Requires the ssh feature. See SSH for usage flows.
microsandbox = { version = "0.5.8", features = ["ssh"] }
use microsandbox::Sandbox;
let sb = Sandbox::builder("api")
.image("python")
.create()
.await?;
let client = sb.ssh().connect().await?; // 1. open an SSH client
let out = client.exec("python -V").await?; // 2. run a command
println!("{}", String::from_utf8_lossy(&out.stdout));
client.close().await?; // 3. close the session
fn ssh(&self) -> SandboxSshOps
let client = sb.ssh().connect().await?;
Return the SSH namespace for this sandbox. The namespace holds the SSH client and server helpers; nothing connects until you call connect or server.
SSH namespace for a sandbox, obtained from sb.ssh(). SSH is only supported on local sandboxes; calls error with Unsupported against a cloud backend.
async fn connect(&self) -> MicrosandboxResult<SshClient>
let client = sb.ssh().connect().await?;
let out = client.exec("uname -a").await?;
Connect a native in-process SSH client to this sandbox. Generates an ephemeral Ed25519 client and host key pair, stands up an internal server bound to a duplex stream, and authenticates over public key. Uses default client options (user root, terminal from $TERM, SFTP enabled).
async fn open_client(&self) -> MicrosandboxResult<SshClient>
Alias for connect.
async fn connect_with(
&self,
f: impl FnOnce(SshClientOptionsBuilder) -> SshClientOptionsBuilder,
) -> MicrosandboxResult<SshClient>
let client = sb.ssh().connect_with(|opts| opts
.user("app")
.term("xterm-256color")).await?;
Connect a native in-process SSH client with custom options. The closure configures the login user, terminal name, and whether SFTP is enabled on the internal server.
<p className="msb-label">Parameters</p> <div className="msb-params"> <div className="msb-param"> <div className="msb-param-key"><code>f</code><a className="msb-type" href="#sshclientoptionsbuilder">FnOnce(SshClientOptionsBuilder)</a></div> <div className="msb-param-desc">Configure user, terminal, and SFTP support.</div> </div> </div> <p className="msb-label">Returns</p> <div className="msb-params"> <div className="msb-param"> <div className="msb-param-key"><a className="msb-type" href="#sshclient">SshClient</a></div> <div className="msb-param-desc">Connected SSH client session.</div> </div> </div>async fn open_client_with(
&self,
f: impl FnOnce(SshClientOptionsBuilder) -> SshClientOptionsBuilder,
) -> MicrosandboxResult<SshClient>
Alias for connect_with.
async fn server(&self) -> MicrosandboxResult<SshServer>
let server = sb.ssh().server().await?;
let (client_io, server_io) = tokio::io::duplex(64 * 1024);
server.serve(server_io).await?;
Prepare a reusable SSH server endpoint for this sandbox. Loads or creates the host key and resolves authorized keys from the default authorized-keys file. The returned SshServer is cloneable and can serve many connections.
async fn prepare_server(&self) -> MicrosandboxResult<SshServer>
Alias for server.
async fn server_with(
&self,
f: impl FnOnce(SshServerOptionsBuilder) -> SshServerOptionsBuilder,
) -> MicrosandboxResult<SshServer>
let server = sb.ssh().server_with(|opts| opts
.authorized_key("ssh-ed25519 AAAAC3Nza...")
.user("app")
.sftp(false)).await?;
Prepare a server endpoint with custom host-key, authorization, guest-user, or SFTP options. If no authorized keys are configured, the default authorized-keys file is loaded; an empty key set is an error.
<p className="msb-label">Parameters</p> <div className="msb-params"> <div className="msb-param"> <div className="msb-param-key"><code>f</code><a className="msb-type" href="#sshserveroptionsbuilder">FnOnce(SshServerOptionsBuilder)</a></div> <div className="msb-param-desc">Configure host key, authorized keys, guest user, and SFTP.</div> </div> </div> <p className="msb-label">Returns</p> <div className="msb-params"> <div className="msb-param"> <div className="msb-param-key"><a className="msb-type" href="#sshserver">SshServer</a></div> <div className="msb-param-desc">Reusable SSH server endpoint.</div> </div> </div>async fn prepare_server_with(
&self,
f: impl FnOnce(SshServerOptionsBuilder) -> SshServerOptionsBuilder,
) -> MicrosandboxResult<SshServer>
Alias for server_with.
A connected, native in-process SSH client session, obtained from connect or connect_with. Aborts its internal server task on drop.
async fn exec(&self, command: impl Into<String>) -> MicrosandboxResult<SshOutput>
let out = client.exec("echo hello").await?;
println!("exit {}: {}", out.status, String::from_utf8_lossy(&out.stdout));
Run an SSH exec request and collect stdout, stderr, and the exit status. The command is run through the sandbox's configured shell (default /bin/sh -c). No PTY is requested.
async fn exec_with(
&self,
command: impl Into<String>,
f: impl FnOnce(SshExecOptionsBuilder) -> SshExecOptionsBuilder,
) -> MicrosandboxResult<SshOutput>
let out = client.exec_with("top -bn1", |opts| opts.tty(true)).await?;
Run an SSH exec request with options. The closure can request a PTY via tty; when a PTY is allocated, stderr is folded into stdout.
async fn attach(&self) -> MicrosandboxResult<i32>
let code = client.attach().await?;
println!("shell exited with {code}");
Attach the local terminal to an interactive SSH shell. Requests a PTY sized to the current terminal, puts the terminal into raw mode, forwards keystrokes, relays window-resize events, and returns when the shell exits or the default detach key sequence is typed.
<p className="msb-label">Returns</p> <div className="msb-params"> <div className="msb-param"> <div className="msb-param-key"><span className="msb-type">i32</span></div> <div className="msb-param-desc">Shell exit code (128 if terminated by signal).</div> </div> </div>async fn attach_with(
&self,
f: impl FnOnce(SshAttachOptionsBuilder) -> SshAttachOptionsBuilder,
) -> MicrosandboxResult<i32>
let code = client.attach_with(|opts| opts
.term("xterm-256color")
.detach_keys("ctrl-p,ctrl-q")).await?;
Attach an interactive shell with custom terminal and detach-key options.
<p className="msb-label">Parameters</p> <div className="msb-params"> <div className="msb-param"> <div className="msb-param-key"><code>f</code><a className="msb-type" href="#sshattachoptionsbuilder">FnOnce(SshAttachOptionsBuilder)</a></div> <div className="msb-param-desc">Configure terminal name and detach keys.</div> </div> </div> <p className="msb-label">Returns</p> <div className="msb-params"> <div className="msb-param"> <div className="msb-param-key"><span className="msb-type">i32</span></div> <div className="msb-param-desc">Shell exit code (128 if terminated by signal).</div> </div> </div>async fn sftp(&self) -> MicrosandboxResult<SftpClient>
let sftp = client.sftp().await?;
let mut file = sftp.create("/tmp/hello.txt").await?;
Open an SFTP client session over this SSH connection. Requests the sftp subsystem and returns a high-level SFTP session for reading, writing, and listing files inside the guest.
async fn close(self) -> MicrosandboxResult<()>
client.close().await?;
Close this native SSH client session. Sends a disconnect and aborts the internal server task. Consumes the client.
A reusable SSH server endpoint for a sandbox, obtained from server or server_with. Cloneable; each call to serve handles one connection.
async fn serve<S>(&self, stream: S) -> MicrosandboxResult<()>
where
S: AsyncRead + AsyncWrite + Unpin + Send + 'static,
let server = sb.ssh().server().await?;
let (client_io, server_io) = tokio::io::duplex(64 * 1024);
tokio::spawn(async move { server.serve(server_io).await });
Serve one SSH connection over an ordered duplex stream. Runs the SSH handshake and session loop to completion. Returns when the connection closes.
<p className="msb-label">Parameters</p> <div className="msb-params"> <div className="msb-param"> <div className="msb-param-key"><code>stream</code><span className="msb-type">S: AsyncRead + AsyncWrite</span></div> <div className="msb-param-desc">Ordered duplex SSH transport.</div> </div> </div>async fn serve_connection<S>(&self, stream: S) -> MicrosandboxResult<()>
where
S: AsyncRead + AsyncWrite + Unpin + Send + 'static,
Alias for serve.
fn new() -> Self
use microsandbox::SshStdioStream;
let server = sb.ssh().server().await?;
server.serve(SshStdioStream::new()).await?;
Create a stdio SSH transport stream backed by this process's stdin and stdout. Implements AsyncRead and AsyncWrite, so it can be passed straight to serve to bridge an SSH connection over the parent process's standard streams. Also available via Default.
pub const DEFAULT_SSH_HOST: &str = "127.0.0.1";
Default SSH listener host used by the CLI adapter when binding a sandbox SSH endpoint.
pub const DEFAULT_SSH_PORT: u16 = 2222;
Default SSH listener port used by the CLI adapter when binding a sandbox SSH endpoint.
Output from an SSH exec request.
| Field | Type | Description |
|---|---|---|
status | i32 | Exit status code. |
stdout | Bytes | Captured stdout bytes. |
stderr | Bytes | Captured stderr bytes (folded into stdout when a PTY is allocated). |
SSH namespace for a sandbox. Cheap to clone; holds a clone of the sandbox.
| Method | Returns | Description |
|---|---|---|
connect() | SshClient | Open a client with defaults. |
open_client() | SshClient | Alias of connect(). |
connect_with() | SshClient | Open a client with options. |
open_client_with() | SshClient | Alias of connect_with(). |
server() | SshServer | Prepare a server endpoint. |
prepare_server() | SshServer | Alias of server(). |
server_with() | SshServer | Server endpoint with options. |
prepare_server_with() | SshServer | Alias of server_with(). |
Native in-process SSH client session. Aborts its internal server task on drop.
| Method | Returns | Description |
|---|---|---|
exec() | SshOutput | Run a command. |
exec_with() | SshOutput | Run with options. |
attach() | i32 | Interactive shell. |
attach_with() | i32 | Attach with options. |
sftp() | SftpClient | Open an SFTP session. |
close() | () | Close the session. |
Reusable SSH server endpoint for a sandbox. Cloneable.
| Method | Returns | Description |
|---|---|---|
serve() | () | Serve one connection. |
serve_connection() | () | Alias of serve(). |
High-level SFTP client session.
pub type SftpClient = russh_sftp::client::SftpSession;
Ordered duplex stream backed by this process's stdin and stdout. Implements AsyncRead and AsyncWrite.
| Method | Returns | Description |
|---|---|---|
new() | SshStdioStream | Create a stdio transport stream. |
Builder for SSH client options. Defaults: user root, terminal from $TERM (falling back to xterm), SFTP enabled.
| Method | Parameters | Description |
|---|---|---|
user() | impl Into<String> | SSH login user. Default root. |
term() | impl Into<String> | Terminal name for interactive sessions. |
sftp() | bool | Enable or disable SFTP on the internal server. Default true. |
build() | Finalize the options. |
Builder for SSH exec options.
| Method | Parameters | Description |
|---|---|---|
tty() | bool | Request a PTY for the exec channel. Default false. |
build() | Finalize the options. |
Builder for interactive SSH attach options. Default terminal comes from $TERM (falling back to xterm); detach keys default to the standard sequence.
| Method | Parameters | Description |
|---|---|---|
term() | impl Into<String> | Terminal name for the shell. |
detach_keys() | impl Into<String> | Detach key sequence. |
build() | Finalize the options. |
Builder for SSH server options. SFTP is enabled by default; when no authorized keys are provided, the default authorized-keys file is loaded.
| Method | Parameters | Description |
|---|---|---|
host_key_path() | impl Into<PathBuf> | Override the host private key path. |
host_key() | PrivateKey | Use an in-memory host private key. |
authorized_keys_path() | impl Into<PathBuf> | Override the authorized-keys path. |
authorized_key() | impl Into<String> | Add one in-memory authorized public key. |
user() | impl Into<String> | Override the guest user used for exec requests. |
sftp() | bool | Enable or disable SFTP. Default true. |
build() | Finalize the options. |