Added MetadataService with GetHealth and GetVersion

CHANGELOG.md

@@ -16,6 +16,7 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 - Added `GetClients` to `SrsService`, which retrieves a list of units that are connected to SRS and the frequencies they are connected to.
 - Added `SrsConnectEvent` and `SrsDisconnectEvent` events 
 - Added `GetDrawArgumentValue` API for units, which returns the value for drawing. (useful for "hook down", "doors open" checks)
+- Added `AdministrationService` with `GetHealth` and `GetVersion` for quick checks on health (even when DCS mission is unresponsive) and version.
 
 ### Fixed
 - Fixed `MarkAddEvent`, `MarkChangeEvent` and `MarkRemoveEvent` position

protos/dcs/administration/v0/administration.proto

@@ -0,0 +1,26 @@
+syntax = "proto3";
+package dcs.administration.v0;
+option csharp_namespace = "RurouniJones.Dcs.Grpc.V0.Administration";
+option go_package = "github.com/DCS-gRPC/go-bindings/dcs/v0/administration";
+
+//A service to get administrative data like health and version
+service AdministrationService {
+
+  rpc GetHealth(GetHealthRequest) returns (GetHealthResponse) {}
+
+  rpc GetVersion(GetVersionRequest) returns (GetVersionResponse) {}
+}
+
+message GetHealthRequest {
+}
+
+message GetHealthResponse {
+  bool alive = 1;
+}
+
+message GetVersionRequest {
+}
+
+message GetVersionResponse {
+  string version = 1;
+}

protos/dcs/dcs.proto

@@ -2,6 +2,7 @@ syntax = "proto3";
 
 package dcs;
 
+import "dcs/administration/v0/administration.proto";
 import "dcs/atmosphere/v0/atmosphere.proto";
 import "dcs/coalition/v0/coalition.proto";
 import "dcs/common/v0/common.proto";

src/rpc.rs

@@ -10,6 +10,7 @@ pub use self::srs::Srs;
 use crate::shutdown::ShutdownHandle;
 use crate::stats::Stats;
 
+mod administration;
 mod atmosphere;
 mod coalition;
 mod controller;

src/rpc/administration.rs

@@ -0,0 +1,30 @@
+use stubs::administration::v0::administration_service_server::AdministrationService;
+use stubs::*;
+use tonic::async_trait;
+use tonic::{Request, Response, Status};
+
+use super::MissionRpc;
+
+#[async_trait]
+impl AdministrationService for MissionRpc {
+    async fn get_health(
+        &self,
+        _request: Request<administration::v0::GetHealthRequest>,
+    ) -> Result<Response<administration::v0::GetHealthResponse>, Status> {
+        let alive: bool = true;
+        return Ok(Response::new(administration::v0::GetHealthResponse {
+            alive,
+        }));
+    }
+
+    async fn get_version(
+        &self,
+        _request: Request<administration::v0::GetVersionRequest>,
+    ) -> Result<Response<administration::v0::GetVersionResponse>, Status> {
+        const VERSION: Option<&str> = option_env!("CARGO_PKG_VERSION");
+        let version = VERSION.unwrap_or("unknown").to_string();
+        return Ok(Response::new(administration::v0::GetVersionResponse {
+            version,
+        }));
+    }
+}

src/server.rs

@@ -5,6 +5,7 @@ use std::time::Duration;
 
 use dcs_module_ipc::IPC;
 use futures_util::FutureExt;
+use stubs::administration::v0::administration_service_server::AdministrationServiceServer;
 use stubs::atmosphere::v0::atmosphere_service_server::AtmosphereServiceServer;
 use stubs::coalition::v0::coalition_service_server::CoalitionServiceServer;
 use stubs::controller::v0::controller_service_server::ControllerServiceServer;
@@ -205,7 +206,7 @@ async fn try_run(
         srs_transmit,
     } = state;
 
-    let mut mission_rpc =
+    let mut mission_rpc: MissionRpc =
         MissionRpc::new(ipc_mission.clone(), stats.clone(), shutdown_signal.clone());
     let mut hook_rpc = HookRpc::new(ipc_hook, stats, shutdown_signal.clone());
 
@@ -243,6 +244,7 @@ async fn try_run(
     });
 
     transport::Server::builder()
+        .add_service(AdministrationServiceServer::new(mission_rpc.clone()))
         .add_service(AtmosphereServiceServer::new(mission_rpc.clone()))
         .add_service(CoalitionServiceServer::new(mission_rpc.clone()))
         .add_service(ControllerServiceServer::new(mission_rpc.clone()))

stubs/src/administration.rs

@@ -0,0 +1,3 @@
+pub mod v0 {
+    tonic::include_proto!("dcs.administration.v0");
+}

stubs/src/lib.rs

@@ -3,6 +3,7 @@
 #![allow(clippy::derive_partial_eq_without_eq)]
 #![allow(clippy::large_enum_variant)]
 
+pub mod administration;
 pub mod atmosphere;
 pub mod coalition;
 pub mod common;