Implement gRPC on client and server

Pending Testing

AobaClient/src/rpc.rs

@@ -0,0 +1,37 @@
+use std::sync::RwLock;
+
+use aoba::aoba_rpc_client::AobaRpcClient;
+use tonic::transport::Channel;
+
+pub mod aoba {
+	tonic::include_proto!("aoba");
+}
+
+static RPC_CLIENT: RpcConnection = RpcConnection {
+	client: RwLock::new(None),
+};
+
+#[derive(Default)]
+pub struct RpcConnection {
+	client: RwLock<Option<AobaRpcClient<Channel>>>,
+}
+
+impl RpcConnection {
+	pub async fn get_client(&self) -> AobaRpcClient<Channel> {
+		self.ensure_client().await;
+		return self.client.read().unwrap().clone().unwrap();
+	}
+
+	async fn ensure_client(&self) {
+		if self.client.read().unwrap().is_none() {
+			let c = AobaRpcClient::connect("http://localhost:5000")
+				.await
+				.expect("Failed to connect RPC");
+			*self.client.write().unwrap() = Some(c);
+		}
+	}
+}
+
+pub async fn get_rpc_client() -> AobaRpcClient<Channel> {
+	return RPC_CLIENT.get_client().await;
+}