Organize beacon_chain typing

- Implements ClientTypes
- New network BeaconChain type for the networking service

beacon_node/client/src/lib.rs

@@ -10,6 +10,7 @@ pub use client_config::ClientConfig;
 pub use client_types::ClientTypes;
 
 //use beacon_chain::BeaconChain;
+use beacon_chain::BeaconChain;
 use exit_future::{Exit, Signal};
 use network::Service as NetworkService;
 use slog::o;
@@ -20,26 +21,35 @@ use tokio::runtime::TaskExecutor;
 /// Main beacon node client service. This provides the connection and initialisation of the clients
 /// sub-services in multiple threads.
 pub struct Client<T: ClientTypes> {
+    /// Configuration for the lighthouse client.
     config: ClientConfig,
+    /// The beacon chain for the running client.
     beacon_chain: Arc<BeaconChain<T::DB, T::SlotClock, T::ForkChoice>>,
+    /// Reference to the network service.
     pub network: Arc<NetworkService>,
+    /// Future to stop and begin shutdown of the Client.
+    //TODO: Decide best way to handle shutdown
     pub exit: exit_future::Exit,
+    /// The sending future to call to terminate the Client.
+    //TODO: Decide best way to handle shutdown
     pub exit_signal: Signal,
+    /// The clients logger.
     log: slog::Logger,
+    /// Marker to pin the beacon chain generics.
+    phantom: PhantomData<T>,
 }
 
-impl<T: ClientTypes> Client<T> {
-    /// Generate an instance of the client. Spawn and link all internal subprocesses.
+impl<TClientType: ClientTypes> Client<TClientType> {
+    /// Generate an instance of the client. Spawn and link all internal sub-processes.
     pub fn new(
         config: ClientConfig,
-        client_type: T,
         log: slog::Logger,
         executor: &TaskExecutor,
     ) -> error::Result<Self> {
         let (exit_signal, exit) = exit_future::signal();
 
         // generate a beacon chain
-        let beacon_chain = client_type.initialise_beacon_chain(&config);
+        let beacon_chain = TClientType::initialise_beacon_chain(&config);
 
         // Start the network service, libp2p and syncing threads
         // TODO: Add beacon_chain reference to network parameters
@@ -54,6 +64,7 @@ impl<T: ClientTypes> Client<T> {
 
         Ok(Client {
             config,
+            beacon_chain,
             exit,
             exit_signal: exit_signal,
             log,