feat(api): add generic server-side method traits for codegen

grpc/src/server/codegen_api.rs

@@ -0,0 +1,9 @@
+mod bidi_streaming;
+mod client_streaming;
+mod server_streaming;
+mod unary;
+
+pub use bidi_streaming::BidiStreamingMethod;
+pub use client_streaming::ClientStreamingMethod;
+pub use server_streaming::ServerStreamingMethod;
+pub use unary::UnaryMethod;

grpc/src/server/codegen_api/bidi_streaming.rs

@@ -0,0 +1,19 @@
+use crate::server::stream::{PushStream, PushStreamConsumer, PushStreamProducer, PushStreamWriter};
+use crate::ServerStatus;
+
+/// A trait for bidirectional streaming gRPC methods.
+#[trait_variant::make(Send)]
+pub trait BidiStreamingMethod: Send {
+    type Req: Send;
+    type Resp: Send;
+
+    /// Handles a bidirectional streaming request.
+    async fn bidi_streaming<P, C>(
+        &self,
+        req: PushStream<P>,
+        writer: PushStreamWriter<C>,
+    ) -> Result<(), ServerStatus>
+    where
+        P: PushStreamProducer<Item = Self::Req> + Send + 'static,
+        C: PushStreamConsumer<Self::Resp> + Send + 'static;
+}

grpc/src/server/codegen_api/client_streaming.rs

@@ -0,0 +1,19 @@
+use crate::server::message::AsMut;
+use crate::server::stream::{PushStream, PushStreamProducer};
+use crate::ServerStatus;
+
+/// A trait for client streaming gRPC methods.
+#[trait_variant::make(Send)]
+pub trait ClientStreamingMethod: Send {
+    type Req: Send;
+    type Resp: AsMut + Send;
+
+    /// Handles a client streaming request.
+    async fn client_streaming<P>(
+        &self,
+        req: PushStream<P>,
+        resp: <Self::Resp as AsMut>::Mut<'_>,
+    ) -> Result<(), ServerStatus>
+    where
+        P: PushStreamProducer<Item = Self::Req> + Send + 'static;
+}

grpc/src/server/codegen_api/server_streaming.rs

@@ -0,0 +1,19 @@
+use crate::server::message::AsView;
+use crate::server::stream::{PushStreamConsumer, PushStreamWriter};
+use crate::ServerStatus;
+
+/// A trait for server streaming gRPC methods.
+#[trait_variant::make(Send)]
+pub trait ServerStreamingMethod: Send {
+    type Req: AsView + Send;
+    type Resp: Send;
+
+    /// Handles a server streaming request.
+    async fn server_streaming<C>(
+        &self,
+        req: <Self::Req as AsView>::View<'_>,
+        writer: PushStreamWriter<C>,
+    ) -> Result<(), ServerStatus>
+    where
+        C: PushStreamConsumer<Self::Resp> + Send + 'static;
+}

grpc/src/server/codegen_api/unary.rs

@@ -0,0 +1,16 @@
+use crate::server::message::{AsMut, AsView};
+use crate::{ServerStatus, Status};
+
+/// A trait for unary gRPC methods.
+#[trait_variant::make(Send)]
+pub trait UnaryMethod: Send {
+    type Req: AsView + Send;
+    type Resp: AsMut + Send;
+
+    /// Handles a unary request.
+    async fn unary(
+        &self,
+        req: <Self::Req as AsView>::View<'_>,
+        resp: <Self::Resp as AsMut>::Mut<'_>,
+    ) -> Result<(), ServerStatus>;
+}

grpc/src/server/mod.rs

@@ -37,6 +37,11 @@ use crate::service::Service;
 pub mod message;
 pub mod stream;
 
+mod codegen_api;
+pub use codegen_api::{
+    BidiStreamingMethod, ClientStreamingMethod, ServerStreamingMethod, UnaryMethod,
+};
+
 pub struct Server {
     handler: Option<Arc<dyn Service>>,
 }