Crate rexpect

The main crate of Rexpect

Overview

Rexpect is a loose port of pexpect which itself is inspired by Don Libe's expect.

It's main components (depending on your need you can use either of those)

• session: automate stuff in Rust
• reader: a non-blocking reader with buffering, matching on strings/regex/...
• process: spawn a process in a pty

Basic example

extern crate rexpect;

use rexpect::spawn;
use rexpect::errors::*;

fn do_ftp() -> Result<()> {
    let mut p = spawn("ftp speedtest.tele2.net", Some(2000))?;
    p.exp_regex("Name \\(.*\\):")?;
    p.send_line("anonymous")?;
    p.exp_string("Password")?;
    p.send_line("test")?;
    p.exp_string("ftp>")?;
    p.send_line("cd upload")?;
    p.exp_string("successfully changed.\r\nftp>")?;
    p.send_line("pwd")?;
    p.exp_regex("[0-9]+ \"/upload\"")?;
    p.send_line("exit")?;
    p.exp_eof()?;
    Ok(())
}


fn main() {
    do_ftp().unwrap_or_else(|e| panic!("ftp job failed with {}", e));
}

Example with bash

Tip: try the chain of commands first in a bash session. The tricky thing is to get the wait_for_prompt right. What wait_for_prompt actually does is seeking to the next visible prompt. If you forgot to call this once your next call to wait_for_prompt comes out of sync and you're seeking to a prompt printed "above" the last execute().

extern crate rexpect;
use rexpect::spawn_bash;
use rexpect::errors::*;


fn run() -> Result<()> {
    let mut p = spawn_bash(Some(30_000))?;
    p.execute("ping 8.8.8.8", "bytes of data")?;
    p.send_control('z')?;
    p.wait_for_prompt()?;
    p.execute("bg", "suspended")?;
    p.send_line("sleep 1")?;
    p.wait_for_prompt()?;
    p.execute("fg", "continued")?;
    p.send_control('c')?;
    p.exp_string("packet loss")?;
    Ok(())
}

fn main() {
    run().unwrap_or_else(|e| panic!("bash process failed with {}", e));
}

Re-exports

pub use session::spawn;

pub use session::spawn_bash;

pub use session::spawn_python;

pub use session::spawn_stream;

pub use reader::ReadUntil;

Modules

errors
process	Start a process via pty
reader	Unblocking reader which supports waiting for strings/regexes and EOF to be present
session	Main module of rexpect: start new process and interact with it