tendermint-proto: Add a feature flag and generate gRPC server definit…

…ions

- `proto-compiler` uses `tonic-build`
- tendermint-proto can be compiled with std for the `grpc` feature
(as required by the generated `tonic` code)
- the primary motivation is the new gRPC-based PrivVal interface
in Tendermint 0.35
(see informalsystems#1134)

.changelog/unreleased/features/1134-proto-grpc.md

@@ -0,0 +1,2 @@
+- `[tendermint-proto]` Add a feature flag and generate gRPC server definitions
+  ([#1134](https://github.com/informalsystems/tendermint-rs/issues/1134))

proto/Cargo.toml

@@ -16,6 +16,10 @@ description = """
 [package.metadata.docs.rs]
 all-features = true
 
+[features]
+default = []
+grpc = ["tonic"]
+
 [dependencies]
 prost = { version = "0.10", default-features = false }
 prost-types = { version = "0.10", default-features = false }
@@ -27,6 +31,7 @@ num-traits = { version = "0.2", default-features = false }
 num-derive = { version = "0.3", default-features = false }
 time = { version = "0.3.5", default-features = false, features = ["macros", "parsing"] }
 flex-error = { version = "0.4.4", default-features = false }
+tonic = { version = "0.7", optional = true }
 
 [dev-dependencies]
 serde_json = { version = "1.0", default-features = false, features = ["alloc"] }

proto/src/lib.rs

@@ -1,6 +1,6 @@
 //! tendermint-proto library gives the developer access to the Tendermint proto-defined structs.
 
-#![no_std]
+#![cfg_attr(not(feature = "grpc"), no_std)]
 #![deny(warnings, trivial_casts, trivial_numeric_casts, unused_import_braces)]
 #![allow(clippy::large_enum_variant)]
 #![forbid(unsafe_code)]

proto/src/prost/tendermint.privval.rs

@@ -106,3 +106,227 @@ pub enum Errors {
     ReadTimeout = 4,
     WriteTimeout = 5,
 }
+/// Generated server implementations.
+#[cfg(feature = "grpc")]
+pub mod priv_validator_api_server {
+    #![allow(unused_variables, dead_code, missing_docs, clippy::let_unit_value)]
+    use tonic::codegen::*;
+    ///Generated trait containing gRPC methods that should be implemented for use with PrivValidatorApiServer.
+    #[async_trait]
+    pub trait PrivValidatorApi: Send + Sync + 'static {
+        async fn get_pub_key(
+            &self,
+            request: tonic::Request<super::PubKeyRequest>,
+        ) -> Result<tonic::Response<super::PubKeyResponse>, tonic::Status>;
+        async fn sign_vote(
+            &self,
+            request: tonic::Request<super::SignVoteRequest>,
+        ) -> Result<tonic::Response<super::SignedVoteResponse>, tonic::Status>;
+        async fn sign_proposal(
+            &self,
+            request: tonic::Request<super::SignProposalRequest>,
+        ) -> Result<tonic::Response<super::SignedProposalResponse>, tonic::Status>;
+    }
+    #[derive(Debug)]
+    pub struct PrivValidatorApiServer<T: PrivValidatorApi> {
+        inner: _Inner<T>,
+        accept_compression_encodings: (),
+        send_compression_encodings: (),
+    }
+    struct _Inner<T>(Arc<T>);
+    impl<T: PrivValidatorApi> PrivValidatorApiServer<T> {
+        pub fn new(inner: T) -> Self {
+            Self::from_arc(Arc::new(inner))
+        }
+        pub fn from_arc(inner: Arc<T>) -> Self {
+            let inner = _Inner(inner);
+            Self {
+                inner,
+                accept_compression_encodings: Default::default(),
+                send_compression_encodings: Default::default(),
+            }
+        }
+        pub fn with_interceptor<F>(
+            inner: T,
+            interceptor: F,
+        ) -> InterceptedService<Self, F>
+        where
+            F: tonic::service::Interceptor,
+        {
+            InterceptedService::new(Self::new(inner), interceptor)
+        }
+    }
+    impl<T, B> tonic::codegen::Service<http::Request<B>> for PrivValidatorApiServer<T>
+    where
+        T: PrivValidatorApi,
+        B: Body + Send + 'static,
+        B::Error: Into<StdError> + Send + 'static,
+    {
+        type Response = http::Response<tonic::body::BoxBody>;
+        type Error = std::convert::Infallible;
+        type Future = BoxFuture<Self::Response, Self::Error>;
+        fn poll_ready(
+            &mut self,
+            _cx: &mut Context<'_>,
+        ) -> Poll<Result<(), Self::Error>> {
+            Poll::Ready(Ok(()))
+        }
+        fn call(&mut self, req: http::Request<B>) -> Self::Future {
+            let inner = self.inner.clone();
+            match req.uri().path() {
+                "/tendermint.privval.PrivValidatorAPI/GetPubKey" => {
+                    #[allow(non_camel_case_types)]
+                    struct GetPubKeySvc<T: PrivValidatorApi>(pub Arc<T>);
+                    impl<
+                        T: PrivValidatorApi,
+                    > tonic::server::UnaryService<super::PubKeyRequest>
+                    for GetPubKeySvc<T> {
+                        type Response = super::PubKeyResponse;
+                        type Future = BoxFuture<
+                            tonic::Response<Self::Response>,
+                            tonic::Status,
+                        >;
+                        fn call(
+                            &mut self,
+                            request: tonic::Request<super::PubKeyRequest>,
+                        ) -> Self::Future {
+                            let inner = self.0.clone();
+                            let fut = async move { (*inner).get_pub_key(request).await };
+                            Box::pin(fut)
+                        }
+                    }
+                    let accept_compression_encodings = self.accept_compression_encodings;
+                    let send_compression_encodings = self.send_compression_encodings;
+                    let inner = self.inner.clone();
+                    let fut = async move {
+                        let inner = inner.0;
+                        let method = GetPubKeySvc(inner);
+                        let codec = tonic::codec::ProstCodec::default();
+                        let mut grpc = tonic::server::Grpc::new(codec)
+                            .apply_compression_config(
+                                accept_compression_encodings,
+                                send_compression_encodings,
+                            );
+                        let res = grpc.unary(method, req).await;
+                        Ok(res)
+                    };
+                    Box::pin(fut)
+                }
+                "/tendermint.privval.PrivValidatorAPI/SignVote" => {
+                    #[allow(non_camel_case_types)]
+                    struct SignVoteSvc<T: PrivValidatorApi>(pub Arc<T>);
+                    impl<
+                        T: PrivValidatorApi,
+                    > tonic::server::UnaryService<super::SignVoteRequest>
+                    for SignVoteSvc<T> {
+                        type Response = super::SignedVoteResponse;
+                        type Future = BoxFuture<
+                            tonic::Response<Self::Response>,
+                            tonic::Status,
+                        >;
+                        fn call(
+                            &mut self,
+                            request: tonic::Request<super::SignVoteRequest>,
+                        ) -> Self::Future {
+                            let inner = self.0.clone();
+                            let fut = async move { (*inner).sign_vote(request).await };
+                            Box::pin(fut)
+                        }
+                    }
+                    let accept_compression_encodings = self.accept_compression_encodings;
+                    let send_compression_encodings = self.send_compression_encodings;
+                    let inner = self.inner.clone();
+                    let fut = async move {
+                        let inner = inner.0;
+                        let method = SignVoteSvc(inner);
+                        let codec = tonic::codec::ProstCodec::default();
+                        let mut grpc = tonic::server::Grpc::new(codec)
+                            .apply_compression_config(
+                                accept_compression_encodings,
+                                send_compression_encodings,
+                            );
+                        let res = grpc.unary(method, req).await;
+                        Ok(res)
+                    };
+                    Box::pin(fut)
+                }
+                "/tendermint.privval.PrivValidatorAPI/SignProposal" => {
+                    #[allow(non_camel_case_types)]
+                    struct SignProposalSvc<T: PrivValidatorApi>(pub Arc<T>);
+                    impl<
+                        T: PrivValidatorApi,
+                    > tonic::server::UnaryService<super::SignProposalRequest>
+                    for SignProposalSvc<T> {
+                        type Response = super::SignedProposalResponse;
+                        type Future = BoxFuture<
+                            tonic::Response<Self::Response>,
+                            tonic::Status,
+                        >;
+                        fn call(
+                            &mut self,
+                            request: tonic::Request<super::SignProposalRequest>,
+                        ) -> Self::Future {
+                            let inner = self.0.clone();
+                            let fut = async move {
+                                (*inner).sign_proposal(request).await
+                            };
+                            Box::pin(fut)
+                        }
+                    }
+                    let accept_compression_encodings = self.accept_compression_encodings;
+                    let send_compression_encodings = self.send_compression_encodings;
+                    let inner = self.inner.clone();
+                    let fut = async move {
+                        let inner = inner.0;
+                        let method = SignProposalSvc(inner);
+                        let codec = tonic::codec::ProstCodec::default();
+                        let mut grpc = tonic::server::Grpc::new(codec)
+                            .apply_compression_config(
+                                accept_compression_encodings,
+                                send_compression_encodings,
+                            );
+                        let res = grpc.unary(method, req).await;
+                        Ok(res)
+                    };
+                    Box::pin(fut)
+                }
+                _ => {
+                    Box::pin(async move {
+                        Ok(
+                            http::Response::builder()
+                                .status(200)
+                                .header("grpc-status", "12")
+                                .header("content-type", "application/grpc")
+                                .body(empty_body())
+                                .unwrap(),
+                        )
+                    })
+                }
+            }
+        }
+    }
+    impl<T: PrivValidatorApi> Clone for PrivValidatorApiServer<T> {
+        fn clone(&self) -> Self {
+            let inner = self.inner.clone();
+            Self {
+                inner,
+                accept_compression_encodings: self.accept_compression_encodings,
+                send_compression_encodings: self.send_compression_encodings,
+            }
+        }
+    }
+    impl<T: PrivValidatorApi> Clone for _Inner<T> {
+        fn clone(&self) -> Self {
+            Self(self.0.clone())
+        }
+    }
+    impl<T: std::fmt::Debug> std::fmt::Debug for _Inner<T> {
+        fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+            write!(f, "{:?}", self.0)
+        }
+    }
+    impl<T: PrivValidatorApi> tonic::transport::NamedService
+    for PrivValidatorApiServer<T> {
+        const NAME: &'static str = "tendermint.privval.PrivValidatorAPI";
+    }
+}