[rust] Add streams WebTransport client and server examples

examples/rust/streams-web-client/Cargo.toml

@@ -0,0 +1,37 @@
+[package]
+name = "streams-web-client"
+version = "0.1.0"
+
+authors.workspace = true
+categories.workspace = true
+edition.workspace = true
+license.workspace = true
+repository.workspace = true
+
+[dependencies]
+anyhow = { workspace = true, features = ["std"] }
+bytes = { workspace = true }
+clap = { workspace = true, features = [
+    "color",
+    "derive",
+    "error-context",
+    "help",
+    "std",
+    "suggestions",
+    "usage",
+] }
+futures = { workspace = true }
+rustls = { workspace = true }
+tokio = { workspace = true, features = ["rt-multi-thread"] }
+tokio-stream = { workspace = true, features = ["time"] }
+tracing = { workspace = true }
+tracing-subscriber = { workspace = true, features = [
+    "ansi",
+    "env-filter",
+    "fmt",
+] }
+url = { workspace = true }
+wit-bindgen-wrpc = { workspace = true }
+wrpc-transport = { workspace = true }
+wrpc-transport-web = { workspace = true }
+wtransport = { workspace = true }

examples/rust/streams-web-client/src/main.rs

@@ -0,0 +1,143 @@
+use core::time::Duration;
+
+use std::sync::Arc;
+
+use anyhow::Context as _;
+use bytes::Bytes;
+use clap::Parser;
+use futures::{stream, StreamExt as _};
+use rustls::client::danger::{HandshakeSignatureValid, ServerCertVerified, ServerCertVerifier};
+use rustls::pki_types::{CertificateDer, ServerName, UnixTime};
+use rustls::version::TLS13;
+use rustls::{DigitallySignedStruct, SignatureScheme};
+use tokio::{time, try_join};
+use tokio_stream::wrappers::IntervalStream;
+use tracing::debug;
+use url::Url;
+use wtransport::{ClientConfig, Endpoint};
+
+mod bindings {
+    wit_bindgen_wrpc::generate!({
+        with: {
+            "wrpc-examples:streams/handler": generate
+        }
+    });
+}
+
+use bindings::wrpc_examples::streams::handler::{echo, Req};
+
+#[derive(Parser, Debug)]
+#[command(author, version, about, long_about = None)]
+struct Args {
+    /// Address to invoke `wrpc-examples:streams/handler.echo` on
+    #[arg(default_value = "https://localhost:4433")]
+    addr: Url,
+}
+
+#[derive(Debug)]
+struct Insecure;
+
+impl ServerCertVerifier for Insecure {
+    fn verify_server_cert(
+        &self,
+        _end_entity: &CertificateDer<'_>,
+        _intermediates: &[CertificateDer<'_>],
+        _server_name: &ServerName<'_>,
+        _ocsp_response: &[u8],
+        _now: UnixTime,
+    ) -> Result<ServerCertVerified, rustls::Error> {
+        Ok(ServerCertVerified::assertion())
+    }
+
+    fn verify_tls12_signature(
+        &self,
+        _message: &[u8],
+        _cert: &CertificateDer<'_>,
+        _dss: &DigitallySignedStruct,
+    ) -> Result<HandshakeSignatureValid, rustls::Error> {
+        Ok(HandshakeSignatureValid::assertion())
+    }
+
+    fn verify_tls13_signature(
+        &self,
+        _message: &[u8],
+        _cert: &CertificateDer<'_>,
+        _dss: &DigitallySignedStruct,
+    ) -> Result<HandshakeSignatureValid, rustls::Error> {
+        Ok(HandshakeSignatureValid::assertion())
+    }
+
+    fn supported_verify_schemes(&self) -> Vec<SignatureScheme> {
+        vec![SignatureScheme::ECDSA_NISTP256_SHA256]
+    }
+}
+
+#[tokio::main]
+async fn main() -> anyhow::Result<()> {
+    tracing_subscriber::fmt().init();
+
+    let Args { addr } = Args::parse();
+
+    let conf = rustls::ClientConfig::builder_with_protocol_versions(&[&TLS13])
+        .dangerous()
+        .with_custom_certificate_verifier(Arc::new(Insecure))
+        .with_no_client_auth();
+
+    let ep = Endpoint::client(
+        ClientConfig::builder()
+            .with_bind_default()
+            .with_custom_tls(conf)
+            .build(),
+    )
+    .context("failed to create endpoint")?;
+
+    let session = ep
+        .connect(&addr)
+        .await
+        .context("failed to connect to server")?;
+    let wrpc = wrpc_transport_web::Client::from(session);
+
+    let numbers = Box::pin(
+        stream::iter(1..)
+            .take(10)
+            .zip(IntervalStream::new(time::interval(Duration::from_secs(1))))
+            .map(|(i, _)| i)
+            .ready_chunks(10),
+    );
+
+    // `stream<u8>` items are chunked using [`Bytes`]
+    let bytes = Box::pin(
+        stream::iter(b"foo bar baz")
+            .zip(IntervalStream::new(time::interval(Duration::from_secs(1))))
+            .map(|(i, _)| *i)
+            .ready_chunks(10)
+            .map(Bytes::from),
+    );
+
+    let (mut numbers, mut bytes, io) = echo(&wrpc, (), Req { numbers, bytes })
+        .await
+        .context("failed to invoke `wrpc-examples:streams/handler.echo`")?;
+    try_join!(
+        async {
+            if let Some(io) = io {
+                debug!("performing async I/O");
+                io.await.context("failed to complete async I/O")
+            } else {
+                Ok(())
+            }
+        },
+        async {
+            while let Some(item) = numbers.next().await {
+                eprintln!("numbers: {item:?}");
+            }
+            Ok(())
+        },
+        async {
+            while let Some(item) = bytes.next().await {
+                eprintln!("bytes: {item:?}");
+            }
+            Ok(())
+        }
+    )?;
+    Ok(())
+}

examples/rust/streams-web-client/wit/deps.lock

@@ -0,0 +1,4 @@
+[streams]
+path = "../../../wit/streams"
+sha256 = "5064bee90ebea73f1695987191fbbfea71ed2dbb69839814009490b4fbe8e96f"
+sha512 = "dfca3844d91c6c8e83fefd7b9511a366b464cf69d017c61b671409cb26dc9490a0e59a8e60ef15b77fdeb4fc1b8d9e6efa11c2fb1a1dabd0141e5e6afe8a59b9"

examples/rust/streams-web-client/wit/deps.toml

@@ -0,0 +1 @@
+streams = "../../../wit/streams"

examples/rust/streams-web-client/wit/deps/streams/streams.wit

@@ -0,0 +1,17 @@
+package wrpc-examples:streams;
+
+interface handler {
+    record req {
+        numbers: stream<u64>,
+        bytes: stream<u8>,
+    }
+    echo: func(r: req) -> (numbers: stream<u64>, bytes: stream<u8>);
+}
+
+world client {
+    import handler;
+}
+
+world server {
+    export handler;
+}

examples/rust/streams-web-client/wit/world.wit

@@ -0,0 +1,5 @@
+package wrpc-examples:streams-rust-client;
+
+world client {
+    include wrpc-examples:streams/client;
+}

examples/rust/streams-web-server/Cargo.toml

@@ -0,0 +1,36 @@
+[package]
+name = "streams-web-server"
+version = "0.1.0"
+
+authors.workspace = true
+categories.workspace = true
+edition.workspace = true
+license.workspace = true
+repository.workspace = true
+
+[dependencies]
+anyhow = { workspace = true, features = ["std"] }
+bytes = { workspace = true }
+clap = { workspace = true, features = [
+    "color",
+    "derive",
+    "error-context",
+    "help",
+    "std",
+    "suggestions",
+    "usage",
+] }
+futures = { workspace = true }
+rcgen = { workspace = true, features = ["crypto", "ring", "zeroize"] }
+rustls = { workspace = true }
+tokio = { workspace = true, features = ["net", "rt-multi-thread", "signal"] }
+tracing = { workspace = true }
+tracing-subscriber = { workspace = true, features = [
+    "ansi",
+    "env-filter",
+    "fmt",
+] }
+wit-bindgen-wrpc = { workspace = true }
+wrpc-transport = { workspace = true }
+wrpc-transport-web = { workspace = true }
+wtransport = { workspace = true }