From ee6a0ccb92bca9a49b023533155e8b837ab8bfe0 Mon Sep 17 00:00:00 2001
From: Age Manning <Age@AgeManning.com>
Date: Fri, 22 Mar 2019 13:37:24 +1100
Subject: [PATCH] Initial build of server-side BeaconNodeService RPC

---
 beacon_node/client/src/lib.rs      |  2 +-
 beacon_node/rpc/Cargo.toml         |  8 ++---
 beacon_node/rpc/src/beacon_node.rs | 50 ++++++++++++++++++++++++++++++
 beacon_node/rpc/src/lib.rs         | 28 +++++++++++++++--
 4 files changed, 81 insertions(+), 7 deletions(-)
 create mode 100644 beacon_node/rpc/src/beacon_node.rs

diff --git a/beacon_node/client/src/lib.rs b/beacon_node/client/src/lib.rs
index 914e47fcf..d8da18cae 100644
--- a/beacon_node/client/src/lib.rs
+++ b/beacon_node/client/src/lib.rs
@@ -61,7 +61,7 @@ impl<TClientType: ClientTypes> Client<TClientType> {
 
         // spawn the RPC server
         if config.rpc_conf.enabled {
-            rpc::start_server(&config.rpc_conf, &log);
+            rpc::start_server(&config.rpc_conf, beacon_chain.clone(), &log);
         }
 
         Ok(Client {
diff --git a/beacon_node/rpc/Cargo.toml b/beacon_node/rpc/Cargo.toml
index 4c3333ee1..acb68972c 100644
--- a/beacon_node/rpc/Cargo.toml
+++ b/beacon_node/rpc/Cargo.toml
@@ -7,7 +7,10 @@ edition = "2018"
 [dependencies]
 bls = { path = "../../eth2/utils/bls" }
 beacon_chain = { path = "../beacon_chain" }
-
+version = { path = "../version" }
+types = { path = "../../eth2/types" }
+ssz = { path = "../../eth2/utils/ssz" }
+slot_clock = { path = "../../eth2/utils/slot_clock" }
 protos = { path = "../../protos" }
 grpcio = { version = "0.4", default-features = false, features = ["protobuf-codec"] }
 protobuf = "2.0.2"
@@ -16,8 +19,5 @@ db = { path = "../db" }
 dirs = "1.0.3"
 futures = "0.1.23"
 slog = "^2.2.3"
-slot_clock = { path = "../../eth2/utils/slot_clock" }
 slog-term = "^2.4.0"
 slog-async = "^2.3.0"
-types = { path = "../../eth2/types" }
-ssz = { path = "../../eth2/utils/ssz" }
diff --git a/beacon_node/rpc/src/beacon_node.rs b/beacon_node/rpc/src/beacon_node.rs
new file mode 100644
index 000000000..8dd7721fd
--- /dev/null
+++ b/beacon_node/rpc/src/beacon_node.rs
@@ -0,0 +1,50 @@
+use beacon_chain::{db::ClientDB, fork_choice::ForkChoice, slot_clock::SlotClock, BeaconChain};
+use futures::Future;
+use grpcio::{RpcContext, UnarySink};
+use protos::services::{Empty, Fork, NodeInfo};
+use protos::services_grpc::BeaconNodeService;
+use slog::{debug, trace, warn};
+use std::sync::Arc;
+
+#[derive(Clone)]
+pub struct BeaconNodeServiceInstance<T, U, F>
+where
+    T: ClientDB + Clone,
+    U: SlotClock + Clone,
+    F: ForkChoice + Clone,
+{
+    pub chain: Arc<BeaconChain<T, U, F>>,
+    pub log: slog::Logger,
+}
+
+impl<T, U, F> BeaconNodeService for BeaconNodeServiceInstance<T, U, F>
+where
+    T: ClientDB + Clone,
+    U: SlotClock + Clone,
+    F: ForkChoice + Clone,
+{
+    /// Provides basic node information.
+    fn info(&mut self, ctx: RpcContext, _req: Empty, sink: UnarySink<NodeInfo>) {
+        trace!(self.log, "Node info requested via RPC");
+
+        let mut node_info = NodeInfo::new();
+        node_info.set_version(version::version());
+        // get the chain state fork
+        let state_fork = self.chain.state.read().fork.clone();
+        // build the rpc fork struct
+        let mut fork = Fork::new();
+        fork.set_previous_version(state_fork.previous_version.to_vec());
+        fork.set_current_version(state_fork.current_version.to_vec());
+        fork.set_epoch(state_fork.epoch.into());
+        node_info.set_fork(fork);
+
+        node_info.set_chain_id(self.chain.spec.chain_id as u32);
+
+        // send the node_info the requester
+        let error_log = self.log.clone();
+        let f = sink
+            .success(node_info)
+            .map_err(move |e| warn!(error_log, "failed to reply {:?}", e));
+        ctx.spawn(f)
+    }
+}
diff --git a/beacon_node/rpc/src/lib.rs b/beacon_node/rpc/src/lib.rs
index 7f776d7d8..2f2abcc1f 100644
--- a/beacon_node/rpc/src/lib.rs
+++ b/beacon_node/rpc/src/lib.rs
@@ -1,20 +1,44 @@
 mod beacon_block;
+mod beacon_node;
 pub mod config;
 mod validator;
 
 use self::beacon_block::BeaconBlockServiceInstance;
+use self::beacon_node::BeaconNodeServiceInstance;
 use self::validator::ValidatorServiceInstance;
+use beacon_chain::{db::ClientDB, fork_choice::ForkChoice, slot_clock::SlotClock, BeaconChain};
 pub use config::Config as RPCConfig;
 use grpcio::{Environment, Server, ServerBuilder};
-use protos::services_grpc::{create_beacon_block_service, create_validator_service};
+use protos::services_grpc::{
+    create_beacon_block_service, create_beacon_node_service, create_validator_service,
+};
 use std::sync::Arc;
 
 use slog::{info, o};
 
-pub fn start_server(config: &RPCConfig, log: &slog::Logger) -> Server {
+pub fn start_server<T, U, F>(
+    config: &RPCConfig,
+    beacon_chain: Arc<BeaconChain<T, U, F>>,
+    log: &slog::Logger,
+) -> Server
+where
+    T: ClientDB + Clone + 'static,
+    U: SlotClock + Clone + 'static,
+    F: ForkChoice + Clone + 'static,
+{
     let log = log.new(o!("Service"=>"RPC"));
     let env = Arc::new(Environment::new(1));
 
+    // build the individual rpc services
+
+    let beacon_node_service = {
+        let instance = BeaconNodeServiceInstance {
+            chain: beacon_chain.clone(),
+            log: log.clone(),
+        };
+        create_beacon_node_service(instance)
+    };
+
     let beacon_block_service = {
         let instance = BeaconBlockServiceInstance { log: log.clone() };
         create_beacon_block_service(instance)