ugi 0.2.1

Runtime-agnostic Rust request client with HTTP/1.1, HTTP/2, HTTP/3, H2C, WebSocket, SSE, and gRPC support
Documentation
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use std::collections::HashMap;
#[cfg(feature = "rustls")]
use std::sync::Arc;
use std::thread;

use async_net::TcpListener;
#[cfg(feature = "rustls")]
use async_tls::TlsAcceptor;
use bytes::Bytes;
use futures_lite::future::block_on;
use futures_lite::io::{AsyncRead, AsyncReadExt, AsyncWrite, AsyncWriteExt};
#[cfg(feature = "rustls")]
use rcgen::generate_simple_self_signed;
#[cfg(feature = "rustls")]
use rustls::ServerConfig;
use sha1::{Digest, Sha1};
use ugi::{Client, CookieJar, Url, WebSocketMessage};

const WS_ACCEPT_MAGIC: &str = "258EAFA5-E914-47DA-95CA-C5AB0DC85B11";

#[test]
fn websocket_echo_roundtrip_works() {
    let url = block_on(spawn_ws_server(|mut stream, request| async move {
        assert_eq!(request.request_line, "GET /echo HTTP/1.1");
        assert_eq!(request.header("sec-websocket-protocol"), Some("chat.v1"));
        let key = request.header("sec-websocket-key").unwrap().to_owned();
        send_handshake_response(&mut stream, &key, Some("chat.v1"), None)
            .await
            .unwrap();

        let frame = read_client_frame(&mut stream).await.unwrap();
        assert_eq!(frame.opcode, 0x1);
        assert_eq!(String::from_utf8(frame.payload).unwrap(), "hello websocket");
        send_server_frame(&mut stream, 0x1, b"hello websocket")
            .await
            .unwrap();

        let close = read_client_frame(&mut stream).await.unwrap();
        assert_eq!(close.opcode, 0x8);
    }))
    .unwrap();

    let mut ws =
        block_on(async { ugi::ws(format!("{url}/echo")).protocol("chat.v1").await }).unwrap();
    assert_eq!(ws.selected_protocol(), Some("chat.v1"));

    block_on(ws.send_text("hello websocket")).unwrap();
    let message = block_on(ws.next()).unwrap().unwrap();
    assert_eq!(
        message,
        WebSocketMessage::Text("hello websocket".to_owned())
    );
    block_on(ws.close()).unwrap();
}

#[test]
fn client_ws_inherits_base_url_headers_cookies_and_cookie_jar() {
    let url = block_on(spawn_ws_server(|mut stream, request| async move {
        assert_eq!(request.request_line, "GET /chat HTTP/1.1");
        assert_eq!(request.header("authorization"), Some("Bearer token-123"));
        let cookie = request.header("cookie").unwrap_or_default();
        assert!(cookie.contains("manual=1"));
        assert!(cookie.contains("jar_cookie=jar-value"));
        let key = request.header("sec-websocket-key").unwrap().to_owned();
        send_handshake_response(
            &mut stream,
            &key,
            Some("chat.v1"),
            Some("from_server=ok; Path=/"),
        )
        .await
        .unwrap();

        let close = read_client_frame(&mut stream).await.unwrap();
        assert_eq!(close.opcode, 0x8);
    }))
    .unwrap();

    let jar = CookieJar::new();
    let cookie_url = Url::parse(format!("{url}/chat")).unwrap();
    jar.store_set_cookie(&cookie_url, "jar_cookie=jar-value; Path=/")
        .unwrap();

    let client = Client::builder()
        .base_url(&url)
        .unwrap()
        .header("authorization", "Bearer token-123")
        .unwrap()
        .cookie("manual", "1")
        .cookie_jar(jar.clone())
        .build()
        .unwrap();

    let mut ws = block_on(async { client.ws("/chat").protocol("chat.v1").await }).unwrap();
    assert_eq!(ws.selected_protocol(), Some("chat.v1"));
    block_on(ws.close()).unwrap();

    let stored = jar
        .get_cookie_header(&Url::parse(format!("{url}/anything")).unwrap())
        .unwrap_or_default();
    assert!(stored.contains("jar_cookie=jar-value"));
    assert!(stored.contains("from_server=ok"));
}

#[test]
fn websocket_handles_ping_and_close() {
    let url = block_on(spawn_ws_server(|mut stream, request| async move {
        let key = request.header("sec-websocket-key").unwrap().to_owned();
        send_handshake_response(&mut stream, &key, None, None)
            .await
            .unwrap();

        send_server_frame(&mut stream, 0x9, b"abc").await.unwrap();
        let pong = read_client_frame(&mut stream).await.unwrap();
        assert_eq!(pong.opcode, 0xA);
        assert_eq!(pong.payload, b"abc");

        send_server_frame(&mut stream, 0x8, &close_payload(1000, "bye"))
            .await
            .unwrap();
        let close_reply = read_client_frame(&mut stream).await.unwrap();
        assert_eq!(close_reply.opcode, 0x8);
        assert_eq!(close_reply.payload, close_payload(1000, "bye"));
    }))
    .unwrap();

    let mut ws = block_on(async { ugi::ws(url).await }).unwrap();

    let ping = block_on(ws.next()).unwrap().unwrap();
    assert_eq!(ping, WebSocketMessage::Ping(Bytes::from_static(b"abc")));

    let close = block_on(ws.next()).unwrap().unwrap();
    assert_eq!(
        close,
        WebSocketMessage::Close(Some(ugi::CloseFrame {
            code: 1000,
            reason: "bye".to_owned(),
        }))
    );
    assert!(block_on(ws.next()).is_none());
}

#[test]
fn websocket_reassembles_fragmented_text_message() {
    // RFC 6455 §5.4: a message may be split into multiple frames.
    // The first frame has FIN=0 and opcode=0x1 (text).
    // Continuation frames have FIN=0/1 and opcode=0x0.
    // The last frame has FIN=1 and opcode=0x0.
    let url = block_on(spawn_ws_server(|mut stream, request| async move {
        let key = request.header("sec-websocket-key").unwrap().to_owned();
        send_handshake_response(&mut stream, &key, None, None)
            .await
            .unwrap();

        // Send "hello " as a non-final text frame (FIN=0, opcode=0x1)
        send_server_frame_fin(&mut stream, false, 0x1, b"hello ")
            .await
            .unwrap();
        // Send "world" as a final continuation frame (FIN=1, opcode=0x0)
        send_server_frame_fin(&mut stream, true, 0x0, b"world")
            .await
            .unwrap();

        // Wait for client close
        let _close = read_client_frame(&mut stream).await.unwrap();
    }))
    .unwrap();

    let mut ws = block_on(async { ugi::ws(url).await }).unwrap();

    let message = block_on(ws.next()).unwrap().unwrap();
    assert_eq!(
        message,
        WebSocketMessage::Text("hello world".to_owned()),
        "fragmented text frames must be reassembled into a single message"
    );
    block_on(ws.close()).unwrap();
}

#[test]
fn websocket_reassembles_fragmented_binary_message() {
    let url = block_on(spawn_ws_server(|mut stream, request| async move {
        let key = request.header("sec-websocket-key").unwrap().to_owned();
        send_handshake_response(&mut stream, &key, None, None)
            .await
            .unwrap();

        // Three binary fragments: [0x01, 0x02], [0x03, 0x04], [0x05]
        send_server_frame_fin(&mut stream, false, 0x2, &[0x01, 0x02])
            .await
            .unwrap();
        send_server_frame_fin(&mut stream, false, 0x0, &[0x03, 0x04])
            .await
            .unwrap();
        send_server_frame_fin(&mut stream, true, 0x0, &[0x05])
            .await
            .unwrap();

        let _close = read_client_frame(&mut stream).await.unwrap();
    }))
    .unwrap();

    let mut ws = block_on(async { ugi::ws(url).await }).unwrap();

    let message = block_on(ws.next()).unwrap().unwrap();
    assert_eq!(
        message,
        WebSocketMessage::Binary(Bytes::from_static(&[0x01, 0x02, 0x03, 0x04, 0x05])),
        "fragmented binary frames must be reassembled into a single message"
    );
    block_on(ws.close()).unwrap();
}

#[test]
fn websocket_interleaves_control_frame_in_fragmented_message() {
    // Control frames (ping) may appear between fragmented data frames per RFC 6455 §5.5.
    let url = block_on(spawn_ws_server(|mut stream, request| async move {
        let key = request.header("sec-websocket-key").unwrap().to_owned();
        send_handshake_response(&mut stream, &key, None, None)
            .await
            .unwrap();

        // Start fragmented message
        send_server_frame_fin(&mut stream, false, 0x1, b"part-one-")
            .await
            .unwrap();
        // Interleave a ping (FIN=1, opcode=0x9)
        send_server_frame_fin(&mut stream, true, 0x9, b"ping-data")
            .await
            .unwrap();
        // Read the pong from client before sending the rest
        let pong = read_client_frame(&mut stream).await.unwrap();
        assert_eq!(pong.opcode, 0xA, "client must respond to ping with pong");
        assert_eq!(pong.payload, b"ping-data");

        // Complete the fragmented message
        send_server_frame_fin(&mut stream, true, 0x0, b"part-two")
            .await
            .unwrap();

        let _close = read_client_frame(&mut stream).await.unwrap();
    }))
    .unwrap();

    let mut ws = block_on(async { ugi::ws(url).await }).unwrap();

    // The ping should surface first, before the complete text message.
    let ping = block_on(ws.next()).unwrap().unwrap();
    assert_eq!(
        ping,
        WebSocketMessage::Ping(Bytes::from_static(b"ping-data"))
    );

    let message = block_on(ws.next()).unwrap().unwrap();
    assert_eq!(
        message,
        WebSocketMessage::Text("part-one-part-two".to_owned()),
        "reassembled message must combine all fragments"
    );
    block_on(ws.close()).unwrap();
}

#[test]
#[cfg(feature = "rustls")]
fn wss_roundtrip_works_with_invalid_cert_override() {
    let url = block_on(spawn_wss_server(|mut stream, request| async move {
        assert_eq!(request.request_line, "GET /secure HTTP/1.1");
        let key = request.header("sec-websocket-key").unwrap().to_owned();
        send_handshake_response(&mut stream, &key, None, None)
            .await
            .unwrap();

        let frame = read_client_frame(&mut stream).await.unwrap();
        assert_eq!(frame.opcode, 0x1);
        assert_eq!(String::from_utf8(frame.payload).unwrap(), "secure hello");
        send_server_frame(&mut stream, 0x1, b"secure hello")
            .await
            .unwrap();

        let close = read_client_frame(&mut stream).await.unwrap();
        assert_eq!(close.opcode, 0x8);
    }))
    .unwrap();

    let mut ws = block_on(async {
        ugi::ws(format!("{url}/secure"))
            .danger_accept_invalid_certs(true)
            .await
    })
    .unwrap();
    block_on(ws.send_text("secure hello")).unwrap();
    let message = block_on(ws.next()).unwrap().unwrap();
    assert_eq!(message, WebSocketMessage::Text("secure hello".to_owned()));
    block_on(ws.close()).unwrap();
}

#[test]
#[cfg(all(feature = "rustls", feature = "btls-backend"))]
fn wss_roundtrip_works_with_boring_backend() {
    let url = block_on(spawn_wss_server(|mut stream, request| async move {
        assert_eq!(request.request_line, "GET /secure HTTP/1.1");
        let key = request.header("sec-websocket-key").unwrap().to_owned();
        send_handshake_response(&mut stream, &key, None, None)
            .await
            .unwrap();

        let frame = read_client_frame(&mut stream).await.unwrap();
        assert_eq!(frame.opcode, 0x1);
        assert_eq!(String::from_utf8(frame.payload).unwrap(), "boring hello");
        send_server_frame(&mut stream, 0x1, b"boring hello")
            .await
            .unwrap();

        let close = read_client_frame(&mut stream).await.unwrap();
        assert_eq!(close.opcode, 0x8);
    }))
    .unwrap();

    let mut ws = block_on(async {
        ugi::ws(format!("{url}/secure"))
            .tls_backend(ugi::TlsBackend::Boring)
            .danger_accept_invalid_certs(true)
            .await
    })
    .unwrap();

    block_on(ws.send_text("boring hello")).unwrap();
    let message = block_on(ws.next()).unwrap().unwrap();
    assert_eq!(message, WebSocketMessage::Text("boring hello".to_owned()));
    block_on(ws.close()).unwrap();
}

#[derive(Clone)]
struct HandshakeRequest {
    request_line: String,
    headers: HashMap<String, String>,
}

impl HandshakeRequest {
    fn header(&self, name: &str) -> Option<&str> {
        self.headers
            .get(&name.to_ascii_lowercase())
            .map(String::as_str)
    }
}

struct ClientFrame {
    opcode: u8,
    payload: Vec<u8>,
}

async fn spawn_ws_server<F, Fut>(handler: F) -> ugi::Result<String>
where
    F: FnOnce(async_net::TcpStream, HandshakeRequest) -> Fut + Send + 'static,
    Fut: std::future::Future<Output = ()> + Send + 'static,
{
    let listener = TcpListener::bind(("127.0.0.1", 0)).await.map_err(|err| {
        ugi::Error::with_source(
            ugi::ErrorKind::Transport,
            "failed to bind ws test server",
            err,
        )
    })?;
    let addr = listener.local_addr().map_err(|err| {
        ugi::Error::with_source(
            ugi::ErrorKind::Transport,
            "failed to inspect ws test server",
            err,
        )
    })?;

    thread::spawn(move || {
        block_on(async move {
            let (mut stream, _) = listener.accept().await.unwrap();
            let request = read_handshake_request(&mut stream).await.unwrap();
            handler(stream, request).await;
        });
    });

    Ok(format!("ws://{}", addr))
}

#[cfg(feature = "rustls")]
async fn spawn_wss_server<F, Fut>(handler: F) -> ugi::Result<String>
where
    F: FnOnce(async_tls::server::TlsStream<async_net::TcpStream>, HandshakeRequest) -> Fut
        + Send
        + 'static,
    Fut: std::future::Future<Output = ()> + Send + 'static,
{
    let cert = generate_simple_self_signed(vec!["localhost".into()]).map_err(|err| {
        ugi::Error::with_source(
            ugi::ErrorKind::Transport,
            "failed to generate ws tls certificate",
            err,
        )
    })?;
    let cert_der = rustls::Certificate(cert.cert.der().to_vec());
    let key_der = rustls::PrivateKey(cert.signing_key.serialize_der());
    let server_config = ServerConfig::builder()
        .with_safe_defaults()
        .with_no_client_auth()
        .with_single_cert(vec![cert_der], key_der)
        .map_err(|err| {
            ugi::Error::with_source(
                ugi::ErrorKind::Transport,
                "failed to build ws tls server config",
                err,
            )
        })?;
    let acceptor = TlsAcceptor::from(Arc::new(server_config));

    let listener = TcpListener::bind(("127.0.0.1", 0)).await.map_err(|err| {
        ugi::Error::with_source(
            ugi::ErrorKind::Transport,
            "failed to bind wss test server",
            err,
        )
    })?;
    let addr = listener.local_addr().map_err(|err| {
        ugi::Error::with_source(
            ugi::ErrorKind::Transport,
            "failed to inspect wss test server",
            err,
        )
    })?;

    thread::spawn(move || {
        block_on(async move {
            let (stream, _) = listener.accept().await.unwrap();
            let mut stream = acceptor.accept(stream).await.unwrap();
            let request = read_handshake_request(&mut stream).await.unwrap();
            handler(stream, request).await;
        });
    });

    Ok(format!("wss://localhost:{}", addr.port()))
}

async fn read_handshake_request<S>(stream: &mut S) -> ugi::Result<HandshakeRequest>
where
    S: AsyncRead + Unpin,
{
    let mut buffer = Vec::new();
    loop {
        let mut scratch = [0_u8; 1024];
        let read = stream.read(&mut scratch).await.map_err(|err| {
            ugi::Error::with_source(
                ugi::ErrorKind::Transport,
                "failed to read ws handshake request",
                err,
            )
        })?;
        if read == 0 {
            return Err(ugi::Error::new(
                ugi::ErrorKind::Transport,
                "incomplete ws handshake request",
            ));
        }
        buffer.extend_from_slice(&scratch[..read]);
        if buffer.windows(4).any(|window| window == b"\r\n\r\n") {
            break;
        }
    }

    let end = buffer
        .windows(4)
        .position(|window| window == b"\r\n\r\n")
        .unwrap();
    let text = std::str::from_utf8(&buffer[..end]).map_err(|err| {
        ugi::Error::with_source(
            ugi::ErrorKind::Decode,
            "ws handshake request is not utf-8",
            err,
        )
    })?;

    let mut lines = text.split("\r\n");
    let request_line = lines.next().unwrap_or_default().to_owned();
    let mut headers = HashMap::new();
    for line in lines {
        if line.is_empty() {
            continue;
        }
        if let Some((name, value)) = line.split_once(':') {
            headers.insert(name.trim().to_ascii_lowercase(), value.trim().to_owned());
        }
    }

    Ok(HandshakeRequest {
        request_line,
        headers,
    })
}

async fn send_handshake_response<S>(
    stream: &mut S,
    websocket_key: &str,
    selected_protocol: Option<&str>,
    set_cookie: Option<&str>,
) -> ugi::Result<()>
where
    S: AsyncWrite + Unpin,
{
    let accept = websocket_accept_value(websocket_key);
    let mut response = format!(
        "HTTP/1.1 101 Switching Protocols\r\nConnection: Upgrade\r\nUpgrade: websocket\r\nSec-WebSocket-Accept: {accept}\r\n"
    );
    if let Some(protocol) = selected_protocol {
        response.push_str(&format!("Sec-WebSocket-Protocol: {protocol}\r\n"));
    }
    if let Some(set_cookie) = set_cookie {
        response.push_str(&format!("Set-Cookie: {set_cookie}\r\n"));
    }
    response.push_str("\r\n");
    stream.write_all(response.as_bytes()).await.map_err(|err| {
        ugi::Error::with_source(
            ugi::ErrorKind::Transport,
            "failed to write ws handshake response",
            err,
        )
    })?;
    stream.flush().await.map_err(|err| {
        ugi::Error::with_source(
            ugi::ErrorKind::Transport,
            "failed to flush ws handshake response",
            err,
        )
    })?;
    Ok(())
}

async fn send_server_frame<S>(stream: &mut S, opcode: u8, payload: &[u8]) -> ugi::Result<()>
where
    S: AsyncWrite + Unpin,
{
    send_server_frame_fin(stream, true, opcode, payload).await
}

/// Send a WebSocket frame with explicit FIN bit control.  Set `fin=false` to
/// create a non-final frame (fragmentation), `fin=true` for the final frame.
async fn send_server_frame_fin<S>(
    stream: &mut S,
    fin: bool,
    opcode: u8,
    payload: &[u8],
) -> ugi::Result<()>
where
    S: AsyncWrite + Unpin,
{
    let fin_bit: u8 = if fin { 0x80 } else { 0x00 };
    let mut frame = Vec::with_capacity(payload.len() + 10);
    frame.push(fin_bit | (opcode & 0x0F));
    if payload.len() <= 125 {
        frame.push(payload.len() as u8);
    } else if payload.len() <= u16::MAX as usize {
        frame.push(126);
        frame.extend_from_slice(&(payload.len() as u16).to_be_bytes());
    } else {
        frame.push(127);
        frame.extend_from_slice(&(payload.len() as u64).to_be_bytes());
    }
    frame.extend_from_slice(payload);
    stream.write_all(&frame).await.map_err(|err| {
        ugi::Error::with_source(ugi::ErrorKind::Transport, "failed to write ws frame", err)
    })?;
    stream.flush().await.map_err(|err| {
        ugi::Error::with_source(ugi::ErrorKind::Transport, "failed to flush ws frame", err)
    })?;
    Ok(())
}

async fn read_client_frame<S>(stream: &mut S) -> ugi::Result<ClientFrame>
where
    S: AsyncRead + Unpin,
{
    let mut header = [0_u8; 2];
    stream.read_exact(&mut header).await.map_err(|err| {
        ugi::Error::with_source(ugi::ErrorKind::Transport, "failed to read ws frame", err)
    })?;

    let opcode = header[0] & 0x0F;
    let masked = header[1] & 0x80 != 0;
    assert!(masked, "client websocket frames must be masked");

    let payload_len = match header[1] & 0x7F {
        len @ 0..=125 => len as usize,
        126 => {
            let mut extended = [0_u8; 2];
            stream.read_exact(&mut extended).await.map_err(|err| {
                ugi::Error::with_source(
                    ugi::ErrorKind::Transport,
                    "failed to read ws extended frame length",
                    err,
                )
            })?;
            u16::from_be_bytes(extended) as usize
        }
        127 => {
            let mut extended = [0_u8; 8];
            stream.read_exact(&mut extended).await.map_err(|err| {
                ugi::Error::with_source(
                    ugi::ErrorKind::Transport,
                    "failed to read ws extended frame length",
                    err,
                )
            })?;
            u64::from_be_bytes(extended) as usize
        }
        _ => unreachable!(),
    };

    let mut mask = [0_u8; 4];
    stream.read_exact(&mut mask).await.map_err(|err| {
        ugi::Error::with_source(ugi::ErrorKind::Transport, "failed to read ws mask", err)
    })?;
    let mut payload = vec![0_u8; payload_len];
    stream.read_exact(&mut payload).await.map_err(|err| {
        ugi::Error::with_source(
            ugi::ErrorKind::Transport,
            "failed to read ws frame payload",
            err,
        )
    })?;
    for (index, byte) in payload.iter_mut().enumerate() {
        *byte ^= mask[index % mask.len()];
    }

    Ok(ClientFrame { opcode, payload })
}

fn close_payload(code: u16, reason: &str) -> Vec<u8> {
    let mut payload = Vec::with_capacity(2 + reason.len());
    payload.extend_from_slice(&code.to_be_bytes());
    payload.extend_from_slice(reason.as_bytes());
    payload
}

fn websocket_accept_value(websocket_key: &str) -> String {
    let mut hasher = Sha1::new();
    hasher.update(websocket_key.as_bytes());
    hasher.update(WS_ACCEPT_MAGIC.as_bytes());
    encode_base64(&hasher.finalize())
}

fn encode_base64(bytes: &[u8]) -> String {
    const TABLE: &[u8; 64] = b"ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/";
    let mut output = String::new();
    let mut chunks = bytes.chunks_exact(3);
    for chunk in &mut chunks {
        let n = ((chunk[0] as u32) << 16) | ((chunk[1] as u32) << 8) | chunk[2] as u32;
        output.push(TABLE[((n >> 18) & 0x3F) as usize] as char);
        output.push(TABLE[((n >> 12) & 0x3F) as usize] as char);
        output.push(TABLE[((n >> 6) & 0x3F) as usize] as char);
        output.push(TABLE[(n & 0x3F) as usize] as char);
    }

    let rem = chunks.remainder();
    if !rem.is_empty() {
        let first = rem[0] as u32;
        let second = rem.get(1).copied().unwrap_or_default() as u32;
        let n = (first << 16) | (second << 8);
        output.push(TABLE[((n >> 18) & 0x3F) as usize] as char);
        output.push(TABLE[((n >> 12) & 0x3F) as usize] as char);
        if rem.len() == 2 {
            output.push(TABLE[((n >> 6) & 0x3F) as usize] as char);
            output.push('=');
        } else {
            output.push('=');
            output.push('=');
        }
    }

    output
}