72 lines
2.2 KiB
Rust
72 lines
2.2 KiB
Rust
// TODO: the `echo` server uses non-async primitives.
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// When running the tests, you should observe that it hangs, due to a
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// deadlock between the caller and the server.
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// Use `spawn_blocking` inside `echo` to resolve the issue.
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use std::io::{Read, Write};
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use tokio::net::TcpListener;
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pub async fn echo(listener: TcpListener) -> Result<(), anyhow::Error> {
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loop {
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let (socket, _) = listener.accept().await?;
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let mut socket = socket.into_std()?;
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socket.set_nonblocking(false)?;
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let mut buffer = Vec::new();
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socket.read_to_end(&mut buffer)?;
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socket.write_all(&buffer)?;
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}
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}
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#[cfg(test)]
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mod tests {
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use super::*;
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use std::net::SocketAddr;
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use std::panic;
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use tokio::io::{AsyncReadExt, AsyncWriteExt};
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use tokio::task::JoinSet;
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async fn bind_random() -> (TcpListener, SocketAddr) {
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let listener = TcpListener::bind("127.0.0.1:0").await.unwrap();
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let addr = listener.local_addr().unwrap();
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(listener, addr)
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}
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#[tokio::test]
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async fn test_echo() {
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let (listener, addr) = bind_random().await;
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tokio::spawn(echo(listener));
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let requests = vec![
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"hello here we go with a long message",
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"world",
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"foo",
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"bar",
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];
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let mut join_set = JoinSet::new();
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for request in requests {
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join_set.spawn(async move {
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let mut socket = tokio::net::TcpStream::connect(addr).await.unwrap();
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let (mut reader, mut writer) = socket.split();
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// Send the request
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writer.write_all(request.as_bytes()).await.unwrap();
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// Close the write side of the socket
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writer.shutdown().await.unwrap();
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// Read the response
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let mut buf = Vec::with_capacity(request.len());
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reader.read_to_end(&mut buf).await.unwrap();
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assert_eq!(&buf, request.as_bytes());
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});
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}
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while let Some(outcome) = join_set.join_next().await {
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if let Err(e) = outcome {
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if let Ok(reason) = e.try_into_panic() {
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panic::resume_unwind(reason);
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}
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}
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}
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}
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}
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