typespec_client_core: New web_runtime to support wasm32-unknown-unknown

Cargo.toml

@@ -83,6 +83,7 @@ fe2o3-amqp-types = { version = "0.14" }
 flate2 = "1.1.0"
 futures = "0.3"
 getrandom = { version = "0.3" }
+gloo-timers = { version = "0.3" }
 hmac = { version = "0.12" }
 litemap = "0.7.4"
 log = "0.4"
@@ -121,6 +122,7 @@ tracing = "0.1.40"
 tracing-subscriber = "0.3"
 url = "2.2"
 uuid = { version = "1.17", features = ["v4"] }
+wasm-bindgen-futures = "0.4"
 zerofrom = "0.1.5"
 zip = { version = "4.0.0", default-features = false, features = ["deflate"] }
 

sdk/typespec/typespec_client_core/Cargo.toml

@@ -16,6 +16,7 @@ base64.workspace = true
 bytes.workspace = true
 dyn-clone.workspace = true
 futures.workspace = true
+gloo-timers = { workspace = true, optional = true }
 pin-project.workspace = true
 quick-xml = { workspace = true, optional = true }
 rand.workspace = true
@@ -29,6 +30,7 @@ typespec = { workspace = true, default-features = false }
 typespec_macros = { workspace = true, optional = true }
 url.workspace = true
 uuid.workspace = true
+wasm-bindgen-futures = { workspace = true, optional = true }
 
 [target.'cfg(not(target_family = "wasm"))'.dependencies]
 tokio = { workspace = true, features = ["macros", "rt-multi-thread", "time"] }
@@ -57,6 +59,7 @@ reqwest_rustls = [
 ] # Remove dependency on banned `ring` crate; requires manually configuring crypto provider.
 test = [] # Enables extra tracing including error bodies that may contain PII.
 tokio = ["tokio/fs", "tokio/sync", "tokio/time", "tokio/io-util"]
+wasm-bindgen = ["dep:wasm-bindgen-futures", "gloo-timers/futures"]
 xml = ["dep:quick-xml"]
 
 [[example]]

sdk/typespec/typespec_client_core/src/async_runtime/mod.rs

@@ -41,6 +41,9 @@ mod standard_runtime;
 #[cfg(feature = "tokio")]
 mod tokio_runtime;
 
+#[cfg(target_arch = "wasm32")]
+mod web_runtime;
+
 #[cfg(test)]
 mod tests;
 
@@ -107,7 +110,7 @@ pub trait AsyncRuntime: Send + Sync {
     ///
     fn spawn(&self, f: TaskFuture) -> SpawnedTask;
 
-    fn sleep(&self, duration: Duration) -> Pin<Box<dyn Future<Output = ()> + Send + 'static>>;
+    fn sleep(&self, duration: Duration) -> TaskFuture;
 }
 
 static ASYNC_RUNTIME_IMPLEMENTATION: OnceLock<Arc<dyn AsyncRuntime>> = OnceLock::new();
@@ -189,12 +192,16 @@ pub fn set_async_runtime(runtime: Arc<dyn AsyncRuntime>) -> crate::Result<()> {
 }
 
 fn create_async_runtime() -> Arc<dyn AsyncRuntime> {
-    #[cfg(not(feature = "tokio"))]
+    #[cfg(feature = "wasm-bindgen")]
     {
-        Arc::new(standard_runtime::StdRuntime)
+        Arc::new(web_runtime::WasmBindgenRuntime) as Arc<dyn AsyncRuntime>
     }
     #[cfg(feature = "tokio")]
     {
         Arc::new(tokio_runtime::TokioRuntime) as Arc<dyn AsyncRuntime>
     }
+    #[cfg(not(any(feature = "tokio", feature = "wasm-bindgen")))]
+    {
+        Arc::new(standard_runtime::StdRuntime)
+    }
 }

sdk/typespec/typespec_client_core/src/async_runtime/standard_runtime.rs

@@ -14,6 +14,7 @@ use std::{
     task::{Context, Poll, Waker},
     thread,
 };
+#[cfg(not(target_arch = "wasm32"))]
 use std::{future::Future, pin::Pin};
 #[cfg(not(target_arch = "wasm32"))]
 use tracing::debug;
@@ -150,7 +151,7 @@ impl AsyncRuntime for StdRuntime {
     /// Uses a simple thread based implementation for sleep. A more efficient
     /// implementation is available by using the `tokio` crate feature.
     #[cfg_attr(target_arch = "wasm32", allow(unused_variables))]
-    fn sleep(&self, duration: Duration) -> Pin<Box<dyn Future<Output = ()> + Send + 'static>> {
+    fn sleep(&self, duration: Duration) -> TaskFuture {
         #[cfg(target_arch = "wasm32")]
         {
             panic!("sleep is not supported on wasm32")

sdk/typespec/typespec_client_core/src/async_runtime/web_runtime.rs

@@ -0,0 +1,36 @@
+// Copyright (c) Microsoft Corporation. All rights reserved.
+// Licensed under the MIT License.
+
+use super::{AsyncRuntime, SpawnedTask, TaskFuture};
+use crate::time::Duration;
+use futures::channel::oneshot;
+
+/// An [`AsyncRuntime`] using `tokio` based APIs.
+pub(crate) struct WasmBindgenRuntime;
+
+impl AsyncRuntime for WasmBindgenRuntime {
+    fn spawn(&self, f: TaskFuture) -> SpawnedTask {
+        let (tx, rx) = oneshot::channel();
+
+        wasm_bindgen_futures::spawn_local(async move {
+            let result = f.await;
+            let _ = tx.send(result);
+        });
+
+        Box::pin(async {
+            rx.await
+                .map_err(|e| Box::new(e) as Box<dyn std::error::Error>)
+        })
+    }
+
+    fn sleep(&self, duration: Duration) -> TaskFuture {
+        Box::pin(async move {
+            if let Ok(d) = duration.try_into() {
+                gloo_timers::future::sleep(d).await;
+            } else {
+                // This means the duration is negative, don't sleep at all.
+                return;
+            }
+        })
+    }
+}

sdk/typespec/typespec_client_core/src/http/policies/retry/mod.rs

@@ -76,7 +76,8 @@ pub fn get_retry_after(headers: &Headers, now: DateTimeFn) -> Option<Duration> {
 ///
 /// `wait` can be implemented in more complex cases where a simple test of time
 /// is not enough.
-#[async_trait]
+#[cfg_attr(target_arch = "wasm32", async_trait(?Send))]
+#[cfg_attr(not(target_arch = "wasm32"), async_trait)]
 pub trait RetryPolicy: std::fmt::Debug + Send + Sync {
     /// Determine if no more retries should be performed.
     ///