async_shell/
lib.rs

1use std::io::{self, Read, Write};
2use std::process::{Command, ExitStatus, Stdio};
3use std::time::Duration;
4
5use async_trait::async_trait;
6use blocking::unblock;
7use wait_timeout::ChildExt as _;
8
9#[derive(Debug)]
10pub struct SpawnAsyncOutput {
11    pub stdout: Vec<u8>,
12    pub stderr: Vec<u8>,
13    pub exit_status: ExitStatus,
14}
15
16#[async_trait]
17pub trait ChildExt {
18    async fn spawn_async(
19        &mut self,
20        stdin: Option<Vec<u8>>,
21        timeout: Option<Duration>,
22        max_size: Option<usize>,
23    ) -> io::Result<SpawnAsyncOutput>;
24}
25
26#[async_trait]
27impl ChildExt for Command {
28    async fn spawn_async(
29        &mut self,
30        stdin: Option<Vec<u8>>,
31        timeout: Option<Duration>,
32        max_size: Option<usize>,
33    ) -> io::Result<SpawnAsyncOutput> {
34        let command = self.stdout(Stdio::piped()).stderr(Stdio::piped());
35        if stdin.is_some() {
36            command.stdin(Stdio::piped());
37        }
38
39        let mut child = command.spawn()?;
40
41        unblock(move || {
42            if let Some(stdin_bytes) = stdin {
43                let stdin = match child.stdin.as_mut() {
44                    Some(stdin) => stdin,
45                    None => unreachable!("never"),
46                };
47                stdin.write_all(&stdin_bytes[..])?;
48            }
49
50            let exit_status =
51                match child.wait_timeout(timeout.unwrap_or_else(|| Duration::from_millis(1000)))? {
52                    Some(exit_status) => exit_status,
53                    None => {
54                        // child hasn't exited yet
55                        child.kill()?;
56                        child.wait()?;
57
58                        return Err(io::Error::new(io::ErrorKind::TimedOut, "run timeout"));
59                    }
60                };
61
62            let max_size = max_size.unwrap_or(2048);
63            let mut buf = vec![0; max_size];
64            buf.resize(max_size, 0);
65
66            let stdout = child
67                .stdout
68                .as_mut()
69                .ok_or_else(|| io::Error::new(io::ErrorKind::Other, "never"))?;
70            let n = stdout.read(&mut buf)?;
71            let stdout_bytes = buf[..n].to_vec();
72
73            let stderr = child
74                .stderr
75                .as_mut()
76                .ok_or_else(|| io::Error::new(io::ErrorKind::Other, "never"))?;
77            let n = stderr.read(&mut buf)?;
78            let stderr_bytes = buf[..n].to_vec();
79
80            Ok(SpawnAsyncOutput {
81                stdout: stdout_bytes,
82                stderr: stderr_bytes,
83                exit_status,
84            })
85        })
86        .await
87    }
88}
async_shell/lib.rs

async_shell/
lib.rs
