Migrate to tonic

.tool-versions

@@ -0,0 +1 @@
+rust 1.67.0

Cargo.toml

@@ -2,6 +2,7 @@
 name = "command_gateway"
 version = "0.1.0"
 edition = "2021"
+publish = false
 
 # See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
 
@@ -17,5 +18,9 @@ name = "client"
 path = "src/client/main.rs"
 
 [dependencies]
-anyhow = "^1.0"
-jsonrpc-derive = "18.0"
+tokio = { version = "1.0", features = ["rt-multi-thread", "macros"] } # Required for tonic
+prost = "0.11" # Required for tonic
+tonic = "0.8"
+
+[build-dependencies]
+tonic-build = { version = "0.8", features = ["prost"] } # Required for tonic

README.md

@@ -0,0 +1,5 @@
+# Project
+
+## Requirements
+
+- `protobuf` see [tonic dependencies](https://github.com/hyperium/tonic#dependencies)

build.rs

@@ -0,0 +1,4 @@
+fn main() -> Result<(), Box<dyn std::error::Error>> {
+    tonic_build::compile_protos("proto/helloworld.proto")?;
+    Ok(())
+}

proto/helloworld.proto

@@ -0,0 +1,17 @@
+syntax = "proto3";
+package helloworld;
+
+service Greeter {
+  // Our SayHello rpc accepts HelloRequests and returns HelloReplies
+  rpc SayHello (HelloRequest) returns (HelloReply);
+}
+
+message HelloRequest {
+  // Request message contains the name to be greeted
+  string name = 1;
+}
+
+message HelloReply {
+  // Reply contains the greeting message
+  string message = 1;
+}

src/client/main.rs

@@ -1,41 +1,21 @@
-use std::os::unix::net::{UnixListener, UnixStream};
-use std::io::{Read, Write};
+use hello_world::greeter_client::GreeterClient;
+use hello_world::HelloRequest;
 
-use anyhow::Context;
-
-fn main() -> anyhow::Result<()> {
-    let socket_path = "mysocket";
-
-    let mut unix_stream =
-        UnixStream::connect(socket_path).context("Could not create stream")?;
-
-    write_request_and_shutdown(&mut unix_stream)?;
-    read_from_stream(&mut unix_stream)?;
-
-    Ok(())
+pub mod hello_world {
+    tonic::include_proto!("helloworld");
 }
 
-fn write_request_and_shutdown(unix_stream: &mut UnixStream) -> anyhow::Result<()> {
-    unix_stream
-        .write(b"Hello?")
-        .context("Failed at writing onto the unix stream")?;
+#[tokio::main]
+async fn main() -> Result<(), Box<dyn std::error::Error>> {
+    let mut client = GreeterClient::connect("http://[::1]:50051").await?;
 
-    println!("We sent a request");
-    println!("Shutting down writing on the stream, waiting for response...");
+    let request = tonic::Request::new(HelloRequest {
+        name: "Tonic".into(),
+    });
 
-    unix_stream
-        .shutdown(std::net::Shutdown::Write)
-        .context("Could not shutdown writing on the stream")?;
+    let response = client.say_hello(request).await?;
 
-    Ok(())
-}
+    println!("RESPONSE={:?}", response);
 
-fn read_from_stream(unix_stream: &mut UnixStream) -> anyhow::Result<()> {
-    let mut response = String::new();
-    unix_stream
-        .read_to_string(&mut response)
-        .context("Failed at reading the unix stream")?;
-
-    println!("We received this response: {}", response);
     Ok(())
 }

src/common/mod.rs

@@ -1 +0,0 @@
-pub mod internal_rpc;

src/daemon/main.rs

@@ -1,39 +1,41 @@
-use std::os::unix::net::{UnixListener, UnixStream};
-use anyhow::Context;
-use std::io::{Read, Write};
+use tonic::{transport::Server, Request, Response, Status};
 
-fn main() -> anyhow::Result<()> {
-    let socket_path = "mysocket";
+use hello_world::greeter_server::{Greeter, GreeterServer};
+use hello_world::{HelloReply, HelloRequest};
 
-    if std::fs::metadata(socket_path).is_ok() {
-        println!("A socket is already present. Deleting...");
-        std::fs::remove_file(socket_path).with_context(|| {
-            format!("could not delete previous socket at {:?}", socket_path)
-        })?;
-    }
+pub mod hello_world {
+    tonic::include_proto!("helloworld");
+}
 
-    let unix_listener =
-        UnixListener::bind(socket_path).context("Could not create the unix socket")?;
+#[derive(Default)]
+pub struct MyGreeter {}
 
-    // put the daemon logic in a loop to accept several connections
-    loop {
-        let (mut unix_stream, socket_address) = unix_listener
-            .accept()
-            .context("Failed at accepting a connection on the unix listener")?;
-        handle_stream(unix_stream)?;
+#[tonic::async_trait]
+impl Greeter for MyGreeter {
+    async fn say_hello(
+        &self,
+        request: Request<HelloRequest>,
+    ) -> Result<Response<HelloReply>, Status> {
+        println!("Got a request from {:?}", request.remote_addr());
+
+        let reply = hello_world::HelloReply {
+            message: format!("Hello {}!", request.into_inner().name),
+        };
+        Ok(Response::new(reply))
     }
 }
 
-fn handle_stream(mut unix_stream: UnixStream) -> anyhow::Result<()> {
-    let mut message = String::new();
-    unix_stream
-        .read_to_string(&mut message)
-        .context("Failed at reading the unix stream")?;
+#[tokio::main]
+async fn main() -> Result<(), Box<dyn std::error::Error>> {
+    let addr = "[::1]:50051".parse().unwrap();
+    let greeter = MyGreeter::default();
 
-    println!("We received this message: {}\nReplying...", message);
+    println!("GreeterServer listening on {}", addr);
+
+    Server::builder()
+        .add_service(GreeterServer::new(greeter))
+        .serve(addr)
+        .await?;
 
-    unix_stream
-        .write(b"I hear you!")
-        .context("Failed at writing onto the unix stream")?;
     Ok(())
 }