feat: Stream chat message (#5498)

* chore: stream message

* chore: stream message

* chore: fix streaming

* chore: fix clippy

frontend/rust-lib/lib-infra/Cargo.toml

@@ -8,7 +8,7 @@ edition = "2018"
 crate-type = ["cdylib", "rlib"]
 
 [dependencies]
-chrono = { workspace = true,  default-features = false, features = ["clock"] }
+chrono = { workspace = true, default-features = false, features = ["clock"] }
 bytes = { version = "1.5" }
 pin-project = "1.1.3"
 futures-core = { version = "0.3" }
@@ -21,6 +21,8 @@ tempfile = "3.8.1"
 validator = "0.16.0"
 tracing.workspace = true
 atomic_refcell = "0.1"
+allo-isolate = { version = "^0.1", features = ["catch-unwind"], optional = true }
+futures = "0.3.30"
 
 [dev-dependencies]
 rand = "0.8.5"
@@ -28,7 +30,8 @@ futures = "0.3.30"
 
 [target.'cfg(not(target_arch = "wasm32"))'.dependencies]
 zip = { version = "0.6.6", features = ["deflate"] }
-brotli = {  version = "3.4.0", optional = true }
+brotli = { version = "3.4.0", optional = true }
 
 [features]
-compression = ["brotli"]
+compression = ["brotli"]
+isolate_flutter = ["allo-isolate"]

frontend/rust-lib/lib-infra/src/isolate_stream.rs

@@ -0,0 +1,44 @@
+use allo_isolate::{IntoDart, Isolate};
+use futures::Sink;
+use pin_project::pin_project;
+use std::pin::Pin;
+use std::task::{Context, Poll};
+
+#[pin_project]
+pub struct IsolateSink {
+  isolate: Isolate,
+}
+
+impl IsolateSink {
+  pub fn new(isolate: Isolate) -> Self {
+    Self { isolate }
+  }
+}
+
+impl<T> Sink<T> for IsolateSink
+where
+  T: IntoDart,
+{
+  type Error = ();
+
+  fn poll_ready(self: Pin<&mut Self>, _cx: &mut Context<'_>) -> Poll<Result<(), Self::Error>> {
+    Poll::Ready(Ok(()))
+  }
+
+  fn start_send(self: Pin<&mut Self>, item: T) -> Result<(), Self::Error> {
+    let this = self.project();
+    if this.isolate.post(item) {
+      Ok(())
+    } else {
+      Err(())
+    }
+  }
+
+  fn poll_flush(self: Pin<&mut Self>, _cx: &mut Context<'_>) -> Poll<Result<(), Self::Error>> {
+    Poll::Ready(Ok(()))
+  }
+
+  fn poll_close(self: Pin<&mut Self>, _cx: &mut Context<'_>) -> Poll<Result<(), Self::Error>> {
+    Poll::Ready(Ok(()))
+  }
+}

frontend/rust-lib/lib-infra/src/lib.rs

@@ -19,6 +19,8 @@ if_wasm! {
   }
 }
 
+#[cfg(feature = "isolate_flutter")]
+pub mod isolate_stream;
 pub mod priority_task;
 pub mod ref_map;
 pub mod util;