Merge RPC branch

Cargo.toml

@@ -29,4 +29,5 @@ members = [
 	"beacon_node/beacon_chain/test_harness",
 	"protos",
 	"validator_client",
+	"account_manager",
 ]

account_manager/Cargo.toml

@@ -0,0 +1,13 @@
+[package]
+name = "account_manager"
+version = "0.0.1"
+authors = ["Luke Anderson <luke@sigmaprime.io>"]
+edition = "2018"
+
+[dependencies]
+bls = { path = "../eth2/utils/bls" }
+clap = "2.32.0"
+slog = "^2.2.3"
+slog-term = "^2.4.0"
+slog-async = "^2.3.0"
+validator_client = { path = "../validator_client" }

account_manager/README.md

@@ -0,0 +1,24 @@
+# Lighthouse Accounts Manager
+
+The accounts manager (AM) is a stand-alone binary which allows
+users to generate and manage the cryptographic keys necessary to
+interact with Ethereum Serenity.
+
+## Roles
+
+The AM is responsible for the following tasks:
+- Generation of cryptographic key pairs
+  - Must acquire sufficient entropy to ensure keys are generated securely (TBD)
+- Secure storage of private keys
+  - Keys must be encrypted while at rest on the disk (TBD)
+  - The format is compatible with the validator client
+- Produces messages and transactions necessary to initiate
+staking on Ethereum 1.x (TPD)
+
+
+## Implementation
+
+The AM is not a service, and does not run continuously, nor does it
+interact with any running services.
+It is intended to be executed separately from other Lighthouse binaries
+and produce files which can be consumed by them.

account_manager/src/main.rs

@@ -0,0 +1,58 @@
+use bls::Keypair;
+use clap::{App, Arg, SubCommand};
+use slog::{debug, info, o, Drain};
+use std::path::PathBuf;
+use validator_client::Config as ValidatorClientConfig;
+
+fn main() {
+    // Logging
+    let decorator = slog_term::TermDecorator::new().build();
+    let drain = slog_term::CompactFormat::new(decorator).build().fuse();
+    let drain = slog_async::Async::new(drain).build().fuse();
+    let log = slog::Logger::root(drain, o!());
+
+    // CLI
+    let matches = App::new("Lighthouse Accounts Manager")
+        .version("0.0.1")
+        .author("Sigma Prime <contact@sigmaprime.io>")
+        .about("Eth 2.0 Accounts Manager")
+        .arg(
+            Arg::with_name("datadir")
+                .long("datadir")
+                .value_name("DIR")
+                .help("Data directory for keys and databases.")
+                .takes_value(true),
+        )
+        .subcommand(
+            SubCommand::with_name("generate")
+                .about("Generates a new validator private key")
+                .version("0.0.1")
+                .author("Sigma Prime <contact@sigmaprime.io>"),
+        )
+        .get_matches();
+
+    let config = ValidatorClientConfig::parse_args(&matches, &log)
+        .expect("Unable to build a configuration for the account manager.");
+
+    // Log configuration
+    info!(log, "";
+          "data_dir" => &config.data_dir.to_str());
+
+    match matches.subcommand() {
+        ("generate", Some(_gen_m)) => {
+            let keypair = Keypair::random();
+            let key_path: PathBuf = config
+                .save_key(&keypair)
+                .expect("Unable to save newly generated private key.");
+            debug!(
+                log,
+                "Keypair generated {:?}, saved to: {:?}",
+                keypair.identifier(),
+                key_path.to_string_lossy()
+            );
+        }
+        _ => panic!(
+            "The account manager must be run with a subcommand. See help for more information."
+        ),
+    }
+}

beacon_node/beacon_chain/src/beacon_chain.rs

@@ -456,8 +456,8 @@ where
     }
 
     /// Produce an `AttestationData` that is valid for the present `slot` and given `shard`.
-    pub fn produce_attestation_data(&self, shard: u64) -> Result<AttestationData, Error> {
-        trace!("BeaconChain::produce_attestation_data: shard: {}", shard);
+    pub fn produce_attestation(&self, shard: u64) -> Result<AttestationData, Error> {
+        trace!("BeaconChain::produce_attestation: shard: {}", shard);
         let source_epoch = self.state.read().current_justified_epoch;
         let source_root = *self.state.read().get_block_root(
             source_epoch.start_slot(self.spec.slots_per_epoch),

beacon_node/beacon_chain/test_harness/src/validator_harness/direct_beacon_node.rs

@@ -50,18 +50,18 @@ impl<T: ClientDB, U: SlotClock, F: ForkChoice> DirectBeaconNode<T, U, F> {
 }
 
 impl<T: ClientDB, U: SlotClock, F: ForkChoice> AttesterBeaconNode for DirectBeaconNode<T, U, F> {
-    fn produce_attestation_data(
+    fn produce_attestation(
         &self,
         _slot: Slot,
         shard: u64,
     ) -> Result<Option<AttestationData>, NodeError> {
-        match self.beacon_chain.produce_attestation_data(shard) {
+        match self.beacon_chain.produce_attestation(shard) {
             Ok(attestation_data) => Ok(Some(attestation_data)),
             Err(e) => Err(NodeError::RemoteFailure(format!("{:?}", e))),
         }
     }
 
-    fn publish_attestation_data(
+    fn publish_attestation(
         &self,
         free_attestation: FreeAttestation,
     ) -> Result<AttestationPublishOutcome, NodeError> {

beacon_node/client/src/lib.rs

@@ -24,12 +24,8 @@ pub struct Client<T: ClientTypes> {
     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,
+    /// Signal to terminate the RPC server.
+    pub rpc_exit_signal: Option<Signal>,
     /// The clients logger.
     log: slog::Logger,
     /// Marker to pin the beacon chain generics.
@@ -43,8 +39,6 @@ impl<TClientType: ClientTypes> Client<TClientType> {
         log: slog::Logger,
         executor: &TaskExecutor,
     ) -> error::Result<Self> {
-        let (exit_signal, exit) = exit_future::signal();
-
         // generate a beacon chain
         let beacon_chain = TClientType::initialise_beacon_chain(&config);
 
@@ -59,16 +53,21 @@ impl<TClientType: ClientTypes> Client<TClientType> {
             network_logger,
         )?;
 
+        let mut rpc_exit_signal = None;
         // spawn the RPC server
         if config.rpc_conf.enabled {
-            rpc::start_server(&config.rpc_conf, &log);
+            rpc_exit_signal = Some(rpc::start_server(
+                &config.rpc_conf,
+                executor,
+                beacon_chain.clone(),
+                &log,
+            ));
         }
 
         Ok(Client {
             config,
             beacon_chain,
-            exit,
-            exit_signal,
+            rpc_exit_signal,
             log,
             network,
             phantom: PhantomData,

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 +19,7 @@ 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" }
+tokio = "0.1.17"
+exit-future = "0.1.4"

beacon_node/rpc/src/beacon_attester.rs

@@ -0,0 +1,61 @@
+use futures::Future;
+use grpcio::{RpcContext, UnarySink};
+use protos::services::{
+    Attestation as AttestationProto, ProduceAttestation, ProduceAttestationResponse,
+    ProduceAttestationRequest, PublishAttestationResponse, PublishAttestationRequest,
+    PublishAttestation
+};
+use protos::services_grpc::BeaconBlockService;
+use slog::Logger;
+
+#[derive(Clone)]
+pub struct AttestationServiceInstance {
+    pub log: Logger,
+}
+
+impl AttestationService for AttestationServiceInstance {
+    /// Produce a `BeaconBlock` for signing by a validator.
+    fn produce_attestation(
+        &mut self,
+        ctx: RpcContext,
+        req: ProduceAttestationRequest,
+        sink: UnarySink<ProduceAttestationResponse>,
+    ) {
+        println!("producing attestation at slot {}", req.get_slot());
+
+        // TODO: build a legit block.
+        let mut attestation = AttestationProto::new();
+        attestation.set_slot(req.get_slot());
+        // TODO Set the shard to something legit.
+        attestation.set_shard(0);
+        attestation.set_block_root(b"cats".to_vec());
+
+        let mut resp = ProduceAttestationResponse::new();
+        resp.set_attestation_data(attestation);
+
+        let f = sink
+            .success(resp)
+            .map_err(move |e| println!("failed to reply {:?}: {:?}", req, e));
+        ctx.spawn(f)
+    }
+
+    /// Accept some fully-formed `BeaconBlock`, process and publish it.
+    fn publish_attestation(
+        &mut self,
+        ctx: RpcContext,
+        req: PublishAttestationRequest,
+        sink: UnarySink<PublishAttestationResponse>,
+    ) {
+        println!("publishing attestation {:?}", req.get_block());
+
+        // TODO: actually process the block.
+        let mut resp = PublishAttestationResponse::new();
+
+        resp.set_success(true);
+
+        let f = sink
+            .success(resp)
+            .map_err(move |e| println!("failed to reply {:?}: {:?}", req, e));
+        ctx.spawn(f)
+    }
+}

beacon_node/rpc/src/beacon_chain.rs

@@ -0,0 +1,31 @@
+use beacon_chain::BeaconChain as RawBeaconChain;
+use beacon_chain::{
+    db::ClientDB,
+    fork_choice::ForkChoice,
+    parking_lot::RwLockReadGuard,
+    slot_clock::SlotClock,
+    types::{BeaconState, ChainSpec},
+    CheckPoint,
+};
+
+/// The RPC's API to the beacon chain.
+pub trait BeaconChain: Send + Sync {
+    fn get_spec(&self) -> &ChainSpec;
+
+    fn get_state(&self) -> RwLockReadGuard<BeaconState>;
+}
+
+impl<T, U, F> BeaconChain for RawBeaconChain<T, U, F>
+where
+    T: ClientDB + Sized,
+    U: SlotClock,
+    F: ForkChoice,
+{
+    fn get_spec(&self) -> &ChainSpec {
+        &self.spec
+    }
+
+    fn get_state(&self) -> RwLockReadGuard<BeaconState> {
+        self.state.read()
+    }
+}

beacon_node/rpc/src/beacon_node.rs

@@ -0,0 +1,46 @@
+use crate::beacon_chain::BeaconChain;
+use futures::Future;
+use grpcio::{RpcContext, UnarySink};
+use protos::services::{Empty, Fork, NodeInfo};
+use protos::services_grpc::BeaconNodeService;
+use slog::{trace, warn};
+use std::sync::Arc;
+
+#[derive(Clone)]
+pub struct BeaconNodeServiceInstance {
+    pub chain: Arc<BeaconChain>,
+    pub log: slog::Logger,
+}
+
+impl BeaconNodeService for BeaconNodeServiceInstance {
+    /// Provides basic node information.
+    fn info(&mut self, ctx: RpcContext, _req: Empty, sink: UnarySink<NodeInfo>) {
+        trace!(self.log, "Node info requested via RPC");
+
+        // build the response
+        let mut node_info = NodeInfo::new();
+        node_info.set_version(version::version());
+
+        // get the chain state
+        let state = self.chain.get_state();
+        let state_fork = state.fork.clone();
+        let genesis_time = state.genesis_time.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_genesis_time(genesis_time);
+        node_info.set_chain_id(self.chain.get_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)
+    }
+}

beacon_node/rpc/src/lib.rs

@@ -1,20 +1,44 @@
 mod beacon_block;
+pub mod beacon_chain;
+mod beacon_node;
 pub mod config;
 mod validator;
 
 use self::beacon_block::BeaconBlockServiceInstance;
+use self::beacon_chain::BeaconChain;
+use self::beacon_node::BeaconNodeServiceInstance;
 use self::validator::ValidatorServiceInstance;
 pub use config::Config as RPCConfig;
+use futures::{future, Future};
 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 slog::{info, o, warn};
 use std::sync::Arc;
+use tokio::runtime::TaskExecutor;
 
-use slog::{info, o};
-
-pub fn start_server(config: &RPCConfig, log: &slog::Logger) -> Server {
+pub fn start_server(
+    config: &RPCConfig,
+    executor: &TaskExecutor,
+    beacon_chain: Arc<BeaconChain>,
+    log: &slog::Logger,
+) -> exit_future::Signal {
     let log = log.new(o!("Service"=>"RPC"));
     let env = Arc::new(Environment::new(1));
 
+    // build a channel to kill the rpc server
+    let (rpc_exit_signal, rpc_exit) = exit_future::signal();
+
+    // 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)
@@ -27,12 +51,26 @@ pub fn start_server(config: &RPCConfig, log: &slog::Logger) -> Server {
     let mut server = ServerBuilder::new(env)
         .register_service(beacon_block_service)
         .register_service(validator_service)
+        .register_service(beacon_node_service)
         .bind(config.listen_address.to_string(), config.port)
         .build()
         .unwrap();
+
+    let spawn_rpc = {
         server.start();
         for &(ref host, port) in server.bind_addrs() {
             info!(log, "gRPC listening on {}:{}", host, port);
         }
+        rpc_exit.and_then(move |_| {
+            info!(log, "RPC Server shutting down");
             server
+                .shutdown()
+                .wait()
+                .map(|_| ())
+                .map_err(|e| warn!(log, "RPC server failed to shutdown: {:?}", e))?;
+            Ok(())
+        })
+    };
+    executor.spawn(spawn_rpc);
+    rpc_exit_signal
 }

eth2/attester/src/lib.rs

@@ -94,7 +94,7 @@ impl<T: SlotClock, U: BeaconNode, V: DutiesReader, W: Signer> Attester<T, U, V,
     }
 
     fn produce_attestation(&mut self, slot: Slot, shard: u64) -> Result<PollOutcome, Error> {
-        let attestation_data = match self.beacon_node.produce_attestation_data(slot, shard)? {
+        let attestation_data = match self.beacon_node.produce_attestation(slot, shard)? {
             Some(attestation_data) => attestation_data,
             None => return Ok(PollOutcome::BeaconNodeUnableToProduceAttestation(slot)),
         };
@@ -120,7 +120,7 @@ impl<T: SlotClock, U: BeaconNode, V: DutiesReader, W: Signer> Attester<T, U, V,
         };
 
         self.beacon_node
-            .publish_attestation_data(free_attestation)?;
+            .publish_attestation(free_attestation)?;
         Ok(PollOutcome::AttestationProduced(slot))
     }
 

eth2/attester/src/test_utils/simulated_beacon_node.rs

@@ -26,7 +26,7 @@ impl SimulatedBeaconNode {
 }
 
 impl BeaconNode for SimulatedBeaconNode {
-    fn produce_attestation_data(&self, slot: Slot, shard: u64) -> ProduceResult {
+    fn produce_attestation(&self, slot: Slot, shard: u64) -> ProduceResult {
         *self.produce_input.write().unwrap() = Some((slot, shard));
         match *self.produce_result.read().unwrap() {
             Some(ref r) => r.clone(),
@@ -34,7 +34,7 @@ impl BeaconNode for SimulatedBeaconNode {
         }
     }
 
-    fn publish_attestation_data(&self, free_attestation: FreeAttestation) -> PublishResult {
+    fn publish_attestation(&self, free_attestation: FreeAttestation) -> PublishResult {
         *self.publish_input.write().unwrap() = Some(free_attestation.clone());
         match *self.publish_result.read().unwrap() {
             Some(ref r) => r.clone(),

eth2/attester/src/traits.rs

@@ -14,13 +14,13 @@ pub enum PublishOutcome {
 
 /// Defines the methods required to produce and publish blocks on a Beacon Node.
 pub trait BeaconNode: Send + Sync {
-    fn produce_attestation_data(
+    fn produce_attestation(
         &self,
         slot: Slot,
         shard: u64,
     ) -> Result<Option<AttestationData>, BeaconNodeError>;
 
-    fn publish_attestation_data(
+    fn publish_attestation(
         &self,
         free_attestation: FreeAttestation,
     ) -> Result<PublishOutcome, BeaconNodeError>;

eth2/types/src/chain_spec.rs

@@ -120,7 +120,7 @@ pub struct ChainSpec {
      *
      */
     pub boot_nodes: Vec<Multiaddr>,
-    pub network_id: u8,
+    pub chain_id: u8,
 }
 
 impl ChainSpec {
@@ -257,7 +257,7 @@ impl ChainSpec {
              * Boot nodes
              */
             boot_nodes: vec![],
-            network_id: 1, // foundation network id
+            chain_id: 1, // foundation chain id
         }
     }
 
@@ -274,7 +274,7 @@ impl ChainSpec {
 
         Self {
             boot_nodes,
-            network_id: 2, // lighthouse testnet network id
+            chain_id: 2, // lighthouse testnet chain id
             ..ChainSpec::few_validators()
         }
     }

eth2/utils/bls/src/keypair.rs

@@ -14,4 +14,8 @@ impl Keypair {
         let pk = PublicKey::from_secret_key(&sk);
         Keypair { sk, pk }
     }
+
+    pub fn identifier(&self) -> String {
+        self.pk.concatenated_hex_id()
+    }
 }

protos/src/services.proto

@@ -12,24 +12,55 @@ syntax = "proto3";
 
 package ethereum.beacon.rpc.v1;
 
+// Service that currently identifies a beacon node
+service BeaconNodeService {
+    rpc Info(Empty) returns (NodeInfo);
+}
+
+/// Service that handles block production
 service BeaconBlockService {
     rpc ProduceBeaconBlock(ProduceBeaconBlockRequest) returns (ProduceBeaconBlockResponse);
     rpc PublishBeaconBlock(PublishBeaconBlockRequest) returns (PublishBeaconBlockResponse);
 }
 
+/// Service that provides the validator client with requisite knowledge about
+//its public keys
 service ValidatorService {
-    // rpc ValidatorAssignment(ValidatorAssignmentRequest) returns (ValidatorAssignmentResponse);
 	rpc ProposeBlockSlot(ProposeBlockSlotRequest) returns (ProposeBlockSlotResponse);
 	rpc ValidatorIndex(PublicKey) returns (IndexResponse);
+    // rpc ValidatorAssignment(ValidatorAssignmentRequest) returns (ValidatorAssignmentResponse);
 }
 
-message BeaconBlock {
-	uint64 slot = 1;
-	bytes block_root = 2;
-	bytes randao_reveal = 3;
-	bytes signature = 4;
+/// Service that handles validator attestations
+service AttestationService {
+	rpc ProduceAttestation(ProduceAttestationRequest) returns (ProduceAttestationResponse);
+	rpc PublishAttestation(PublishAttestationRequest) returns (PublishAttestationResponse);
 }
 
+/*
+ * Beacon Node Service Message
+ */
+message NodeInfo {
+    string version = 1;
+    Fork fork = 2;
+    uint32 chain_id = 3;
+    uint64 genesis_time = 4;
+}
+
+message Fork {
+    bytes previous_version = 1;
+    bytes current_version = 2;
+    uint64 epoch = 3;
+}
+
+message Empty {
+}
+
+
+/*
+ * Block Production Service Messages
+ */
+
 // Validator requests an unsigned proposal.
 message ProduceBeaconBlockRequest {
     uint64 slot = 1;
@@ -51,6 +82,22 @@ message PublishBeaconBlockResponse {
     bytes msg = 2;
 }
 
+message BeaconBlock {
+	uint64 slot = 1;
+	bytes block_root = 2;
+	bytes randao_reveal = 3;
+	bytes signature = 4;
+}
+
+/*
+ * Validator Service Messages
+ */
+/*
+message ValidatorAssignmentRequest {
+	uint64 epoch = 1;
+	bytes validator_index = 2;
+}
+
 // A validators duties for some epoch.
 // TODO: add shard duties.
 message ValidatorAssignment {
@@ -59,15 +106,20 @@ message ValidatorAssignment {
 		uint64 block_production_slot = 2;
 	}
 }
+*/
 
-message ValidatorAssignmentRequest {
-	uint64 epoch = 1;
-	bytes validator_index = 2;
+// Validator Assignment
+
+message PublicKey {
+	bytes public_key = 1;
 }
 
-/*
- * Propose slot
- */
+message IndexResponse {
+	uint64 index = 1;
+}
+
+
+// Propose slot
 
 message ProposeBlockSlotRequest {
 	uint64 epoch = 1;
@@ -81,14 +133,49 @@ message ProposeBlockSlotResponse {
 	}
 }
 
+
 /*
- * Validator Assignment
+ * Attestation Service Messages
  */
 
-message PublicKey {
-	bytes public_key = 1;
+message ProduceAttestationRequest {
+	uint64 slot = 1;
+	uint64 shard = 2;
 }
 
-message IndexResponse {
-	uint64 index = 1;
+message ProduceAttestationResponse {
+	Attestation attestation_data = 1;
+}
+
+message PublishAttestationRequest {
+	FreeAttestation free_attestation = 1;
+}
+
+message PublishAttestationResponse {
+	bool success = 1;
+	bytes msg = 2;
+}
+
+message Crosslink {
+	uint64 epoch = 1;
+	bytes crosslink_data_root = 2;
+
+}
+
+message Attestation {
+	uint64 slot = 1;
+	uint64 shard = 2;
+	bytes beacon_block_root = 3;
+	bytes epoch_boundary_root = 4;
+	bytes crosslink_data_root = 5;
+	Crosslink latest_crosslink = 6;
+	uint64 justified_epoch = 7;
+	bytes justified_block_root = 8;
+
+}
+
+message FreeAttestation {
+	Attestation attestation_data = 1;
+	bytes signature = 2;
+	uint64 validator_index = 3;
 }

validator_client/Cargo.toml

@@ -1,12 +1,23 @@
 [package]
 name = "validator_client"
 version = "0.1.0"
-authors = ["Paul Hauner <paul@paulhauner.com>"]
+authors = ["Paul Hauner <paul@paulhauner.com>", "Age Manning <Age@AgeManning.com>", "Luke Anderson <luke@lukeanderson.com.au>"]
 edition = "2018"
 
+[[bin]]
+name = "validator_client"
+path = "src/main.rs"
+
+[lib]
+name = "validator_client"
+path = "src/lib.rs"
+
+
 [dependencies]
 block_proposer = { path = "../eth2/block_proposer" }
+attester = { path = "../eth2/attester" }
 bls = { path = "../eth2/utils/bls" }
+ssz = { path = "../eth2/utils/ssz" }
 clap = "2.32.0"
 dirs = "1.0.3"
 grpcio = { version = "0.4", default-features = false, features = ["protobuf-codec"] }
@@ -17,4 +28,7 @@ types = { path = "../eth2/types" }
 slog = "^2.2.3"
 slog-term = "^2.4.0"
 slog-async = "^2.3.0"
-ssz = { path = "../eth2/utils/ssz" }
+tokio = "0.1.18"
+tokio-timer = "0.2.10"
+error-chain = "0.12.0"
+bincode = "^1.1.2"

validator_client/README.md

@@ -57,10 +57,30 @@ complete and return a block from the BN.
 
 ### Configuration
 
-Presently the validator specifics (pubkey, etc.) are randomly generated and the
-chain specification (slot length, BLS domain, etc.) are fixed to foundation
-parameters. This is temporary and will be upgrade so these parameters can be
-read from file (or initialized on first-boot).
+Validator configurations are stored in a separate data directory from the main Beacon Node
+binary. The validator data directory defaults to:
+`$HOME/.lighthouse-validator`, however an alternative can be specified on the command line
+with `--datadir`.
+
+The configuration directory structure looks like:
+```
+~/.lighthouse-validator
+    ├── 3cf4210d58ec
+    │   └── private.key
+    ├── 9b5d8b5be4e7
+    │   └── private.key
+    └── cf6e07188f48
+        └── private.key
+```
+
+Where the hex value of the directory is a portion of the validator public key.
+
+Validator keys must be generated using the separate `accounts_manager` binary, which will
+place the keys into this directory structure in a format compatible with the validator client.
+
+The chain specification (slot length, BLS domain, etc.) defaults to foundation
+parameters, however is temporary and an upgrade will allow these parameters to be
+read from a file (or initialized on first-boot).
 
 ## BN Communication
 

validator_client/src/attester_service/attestation_grpc_client.rs

@@ -0,0 +1,44 @@
+use protos::services_grpc::AttestationServiceClient;
+use std::sync::Arc;
+
+use attester::{BeaconNode, BeaconNodeError, PublishOutcome};
+use protos::services::ProduceAttestationRequest;
+use types::{AttestationData, FreeAttestation, Slot};
+
+pub struct AttestationGrpcClient {
+    client: Arc<AttestationServiceClient>,
+}
+
+impl AttestationGrpcClient {
+    pub fn new(client: Arc<AttestationServiceClient>) -> Self {
+        Self { client }
+    }
+}
+
+impl BeaconNode for AttestationGrpcClient {
+    fn produce_attestation(
+        &self,
+        slot: Slot,
+        shard: u64,
+    ) -> Result<Option<AttestationData>, BeaconNodeError> {
+        let mut req = ProduceAttestationRequest::new();
+        req.set_slot(slot.as_u64());
+        req.set_shard(shard);
+
+        let reply = self
+            .client
+            .produce_attestation(&req)
+            .map_err(|err| BeaconNodeError::RemoteFailure(format!("{:?}", err)))?;
+
+        // TODO: return correct Attestation
+        Err(BeaconNodeError::DecodeFailure)
+    }
+
+    fn publish_attestation(
+        &self,
+        free_attestation: FreeAttestation,
+    ) -> Result<PublishOutcome, BeaconNodeError> {
+        // TODO: return correct PublishOutcome
+        Err(BeaconNodeError::DecodeFailure)
+    }
+}

validator_client/src/attester_service/mod.rs

@@ -0,0 +1,54 @@
+mod attestation_grpc_client;
+use attester::{Attester, BeaconNode, DutiesReader, PollOutcome as AttesterPollOutcome, Signer};
+use slog::{error, info, warn, Logger};
+use slot_clock::SlotClock;
+use std::time::Duration;
+
+pub use self::attestation_grpc_client::AttestationGrpcClient;
+
+pub struct AttesterService<T: SlotClock, U: BeaconNode, V: DutiesReader, W: Signer> {
+    pub attester: Attester<T, U, V, W>,
+    pub poll_interval_millis: u64,
+    pub log: Logger,
+}
+
+impl<T: SlotClock, U: BeaconNode, V: DutiesReader, W: Signer> AttesterService<T, U, V, W> {
+    /// Run a loop which polls the Attester each `poll_interval_millis` millseconds.
+    ///
+    /// Logs the results of the polls.
+    pub fn run(&mut self) {
+        loop {
+            match self.attester.poll() {
+                Err(error) => {
+                    error!(self.log, "Attester poll error"; "error" => format!("{:?}", error))
+                }
+                Ok(AttesterPollOutcome::AttestationProduced(slot)) => {
+                    info!(self.log, "Produced Attestation"; "slot" => slot)
+                }
+                Ok(AttesterPollOutcome::SlashableAttestationNotProduced(slot)) => {
+                    warn!(self.log, "Slashable attestation was not produced"; "slot" => slot)
+                }
+                Ok(AttesterPollOutcome::AttestationNotRequired(slot)) => {
+                    info!(self.log, "Attestation not required"; "slot" => slot)
+                }
+                Ok(AttesterPollOutcome::ProducerDutiesUnknown(slot)) => {
+                    error!(self.log, "Attestation duties unknown"; "slot" => slot)
+                }
+                Ok(AttesterPollOutcome::SlotAlreadyProcessed(slot)) => {
+                    warn!(self.log, "Attempted to re-process slot"; "slot" => slot)
+                }
+                Ok(AttesterPollOutcome::BeaconNodeUnableToProduceAttestation(slot)) => {
+                    error!(self.log, "Beacon node unable to produce attestation"; "slot" => slot)
+                }
+                Ok(AttesterPollOutcome::SignerRejection(slot)) => {
+                    error!(self.log, "The cryptographic signer refused to sign the attestation"; "slot" => slot)
+                }
+                Ok(AttesterPollOutcome::ValidatorIsUnknown(slot)) => {
+                    error!(self.log, "The Beacon Node does not recognise the validator"; "slot" => slot)
+                }
+            };
+
+            std::thread::sleep(Duration::from_millis(self.poll_interval_millis));
+        }
+    }
+}

validator_client/src/config.rs

@@ -1,28 +1,38 @@
+use clap::ArgMatches;
+use bincode;
+use bls::Keypair;
+use slog::{debug, error, info};
 use std::fs;
+use std::fs::File;
+use std::io::{Error, ErrorKind};
 use std::path::PathBuf;
 use types::ChainSpec;
 
 /// Stores the core configuration for this validator instance.
 #[derive(Clone)]
-pub struct ClientConfig {
+pub struct Config {
+    /// The data directory, which stores all validator databases
     pub data_dir: PathBuf,
+    /// The server at which the Beacon Node can be contacted
     pub server: String,
+    /// The chain specification that we are connecting to
     pub spec: ChainSpec,
 }
 
-const DEFAULT_LIGHTHOUSE_DIR: &str = ".lighthouse-validators";
+const DEFAULT_PRIVATE_KEY_FILENAME: &str = "private.key";
 
-impl ClientConfig {
+impl Default for Config {
     /// Build a new configuration from defaults.
-    pub fn default() -> Self {
+    fn default() -> Self {
         let data_dir = {
-            let home = dirs::home_dir().expect("Unable to determine home dir.");
-            home.join(DEFAULT_LIGHTHOUSE_DIR)
+            let home = dirs::home_dir().expect("Unable to determine home directory.");
+            home.join(".lighthouse-validator")
         };
-        fs::create_dir_all(&data_dir)
-            .unwrap_or_else(|_| panic!("Unable to create {:?}", &data_dir));
-        let server = "localhost:50051".to_string();
+
+        let server = "localhost:5051".to_string();
+
         let spec = ChainSpec::foundation();
+
         Self {
             data_dir,
             server,
@@ -30,3 +40,119 @@ impl ClientConfig {
         }
     }
 }
+
+impl Config {
+    /// Build a new configuration from defaults, which are overrided by arguments provided.
+    pub fn parse_args(args: &ArgMatches, log: &slog::Logger) -> Result<Self, Error> {
+        let mut config = Config::default();
+
+        // Use the specified datadir, or default in the home directory
+        if let Some(datadir) = args.value_of("datadir") {
+            config.data_dir = PathBuf::from(datadir);
+            info!(log, "Using custom data dir: {:?}", &config.data_dir);
+        };
+
+        fs::create_dir_all(&config.data_dir)
+            .unwrap_or_else(|_| panic!("Unable to create {:?}", &config.data_dir));
+
+        if let Some(srv) = args.value_of("server") {
+            //TODO: Validate the server value, to ensure it makes sense.
+            config.server = srv.to_string();
+            info!(log, "Using custom server: {:?}", &config.server);
+        };
+
+        // TODO: Permit loading a custom spec from file.
+        if let Some(spec_str) = args.value_of("spec") {
+            info!(log, "Using custom spec: {:?}", spec_str);
+            config.spec = match spec_str {
+                "foundation" => ChainSpec::foundation(),
+                "few_validators" => ChainSpec::few_validators(),
+                // Should be impossible due to clap's `possible_values(..)` function.
+                _ => unreachable!(),
+            };
+        };
+        // Log configuration
+        info!(log, "";
+              "data_dir" => &config.data_dir.to_str(),
+              "server" => &config.server);
+
+        Ok(config)
+    }
+
+    /// Try to load keys from validator_dir, returning None if none are found or an error.
+    pub fn fetch_keys(&self, log: &slog::Logger) -> Option<Vec<Keypair>> {
+        let key_pairs: Vec<Keypair> = fs::read_dir(&self.data_dir)
+            .unwrap()
+            .filter_map(|validator_dir| {
+                let validator_dir = validator_dir.ok()?;
+
+                if !(validator_dir.file_type().ok()?.is_dir()) {
+                    // Skip non-directories (i.e. no files/symlinks)
+                    return None;
+                }
+
+                let key_filename = validator_dir.path().join(DEFAULT_PRIVATE_KEY_FILENAME);
+
+                if !(key_filename.is_file()) {
+                    info!(
+                        log,
+                        "Private key is not a file: {:?}",
+                        key_filename.to_str()
+                    );
+                    return None;
+                }
+
+                debug!(
+                    log,
+                    "Deserializing private key from file: {:?}",
+                    key_filename.to_str()
+                );
+
+                let mut key_file = File::open(key_filename.clone()).ok()?;
+
+                let key: Keypair = if let Ok(key_ok) = bincode::deserialize_from(&mut key_file) {
+                    key_ok
+                } else {
+                    error!(
+                        log,
+                        "Unable to deserialize the private key file: {:?}", key_filename
+                    );
+                    return None;
+                };
+
+                let ki = key.identifier();
+                if ki != validator_dir.file_name().into_string().ok()? {
+                    error!(
+                        log,
+                        "The validator key ({:?}) did not match the directory filename {:?}.",
+                        ki,
+                        &validator_dir.path().to_string_lossy()
+                    );
+                    return None;
+                }
+                Some(key)
+            })
+            .collect();
+
+        // Check if it's an empty vector, and return none.
+        if key_pairs.is_empty() {
+            None
+        } else {
+            Some(key_pairs)
+        }
+    }
+
+    /// Saves a keypair to a file inside the appropriate validator directory. Returns the saved path filename.
+    pub fn save_key(&self, key: &Keypair) -> Result<PathBuf, Error> {
+        let validator_config_path = self.data_dir.join(key.identifier());
+        let key_path = validator_config_path.join(DEFAULT_PRIVATE_KEY_FILENAME);
+
+        fs::create_dir_all(&validator_config_path)?;
+
+        let mut key_file = File::create(&key_path)?;
+
+        bincode::serialize_into(&mut key_file, &key)
+            .map_err(|e| Error::new(ErrorKind::InvalidData, e))?;
+        Ok(key_path)
+    }
+}

validator_client/src/duties/mod.rs

@@ -1,21 +1,19 @@
 mod epoch_duties;
 mod grpc;
-mod service;
 #[cfg(test)]
 mod test_node;
 mod traits;
 
 pub use self::epoch_duties::EpochDutiesMap;
 use self::epoch_duties::{EpochDuties, EpochDutiesMapError};
-pub use self::service::DutiesManagerService;
 use self::traits::{BeaconNode, BeaconNodeError};
 use bls::PublicKey;
 use slot_clock::SlotClock;
 use std::sync::Arc;
-use types::{ChainSpec, Epoch};
+use types::{ChainSpec, Epoch, Slot};
 
 #[derive(Debug, PartialEq, Clone, Copy)]
-pub enum PollOutcome {
+pub enum UpdateOutcome {
     /// The `EpochDuties` were not updated during this poll.
     NoChange(Epoch),
     /// The `EpochDuties` for the `epoch` were previously unknown, but obtained in the poll.
@@ -39,45 +37,42 @@ pub enum Error {
 /// A polling state machine which ensures the latest `EpochDuties` are obtained from the Beacon
 /// Node.
 ///
-/// There is a single `DutiesManager` per validator instance.
+/// This keeps track of all validator keys and required voting slots.
 pub struct DutiesManager<T: SlotClock, U: BeaconNode> {
     pub duties_map: Arc<EpochDutiesMap>,
-    /// The validator's public key.
-    pub pubkey: PublicKey,
+    /// A list of all public keys known to the validator service.
+    pub pubkeys: Vec<PublicKey>,
     pub spec: Arc<ChainSpec>,
     pub slot_clock: Arc<T>,
     pub beacon_node: Arc<U>,
 }
 
 impl<T: SlotClock, U: BeaconNode> DutiesManager<T, U> {
-    /// Poll the Beacon Node for `EpochDuties`.
+    /// Check the Beacon Node for `EpochDuties`.
     ///
     /// The present `epoch` will be learned from the supplied `SlotClock`. In production this will
     /// be a wall-clock (e.g., system time, remote server time, etc.).
-    pub fn poll(&self) -> Result<PollOutcome, Error> {
-        let slot = self
-            .slot_clock
-            .present_slot()
-            .map_err(|_| Error::SlotClockError)?
-            .ok_or(Error::SlotUnknowable)?;
-
+    pub fn update(&self, slot: Slot) -> Result<UpdateOutcome, Error> {
         let epoch = slot.epoch(self.spec.slots_per_epoch);
 
-        if let Some(duties) = self.beacon_node.request_shuffling(epoch, &self.pubkey)? {
+        if let Some(duties) = self
+            .beacon_node
+            .request_shuffling(epoch, &self.pubkeys[0])?
+        {
             // If these duties were known, check to see if they're updates or identical.
             let result = if let Some(known_duties) = self.duties_map.get(epoch)? {
                 if known_duties == duties {
-                    Ok(PollOutcome::NoChange(epoch))
+                    Ok(UpdateOutcome::NoChange(epoch))
                 } else {
-                    Ok(PollOutcome::DutiesChanged(epoch, duties))
+                    Ok(UpdateOutcome::DutiesChanged(epoch, duties))
                 }
             } else {
-                Ok(PollOutcome::NewDuties(epoch, duties))
+                Ok(UpdateOutcome::NewDuties(epoch, duties))
             };
             self.duties_map.insert(epoch, duties)?;
             result
         } else {
-            Ok(PollOutcome::UnknownValidatorOrEpoch(epoch))
+            Ok(UpdateOutcome::UnknownValidatorOrEpoch(epoch))
         }
     }
 }

validator_client/src/duties/service.rs

@@ -1,40 +0,0 @@
-use super::traits::BeaconNode;
-use super::{DutiesManager, PollOutcome};
-use slog::{debug, error, info, Logger};
-use slot_clock::SlotClock;
-use std::time::Duration;
-
-pub struct DutiesManagerService<T: SlotClock, U: BeaconNode> {
-    pub manager: DutiesManager<T, U>,
-    pub poll_interval_millis: u64,
-    pub log: Logger,
-}
-
-impl<T: SlotClock, U: BeaconNode> DutiesManagerService<T, U> {
-    /// Run a loop which polls the manager each `poll_interval_millis` milliseconds.
-    ///
-    /// Logs the results of the polls.
-    pub fn run(&mut self) {
-        loop {
-            match self.manager.poll() {
-                Err(error) => {
-                    error!(self.log, "Epoch duties poll error"; "error" => format!("{:?}", error))
-                }
-                Ok(PollOutcome::NoChange(epoch)) => {
-                    debug!(self.log, "No change in duties"; "epoch" => epoch)
-                }
-                Ok(PollOutcome::DutiesChanged(epoch, duties)) => {
-                    info!(self.log, "Duties changed (potential re-org)"; "epoch" => epoch, "duties" => format!("{:?}", duties))
-                }
-                Ok(PollOutcome::NewDuties(epoch, duties)) => {
-                    info!(self.log, "New duties obtained"; "epoch" => epoch, "duties" => format!("{:?}", duties))
-                }
-                Ok(PollOutcome::UnknownValidatorOrEpoch(epoch)) => {
-                    error!(self.log, "Epoch or validator unknown"; "epoch" => epoch)
-                }
-            };
-
-            std::thread::sleep(Duration::from_millis(self.poll_interval_millis));
-        }
-    }
-}

validator_client/src/error.rs

@@ -0,0 +1,22 @@
+use slot_clock;
+
+use error_chain::{
+    error_chain, error_chain_processing, impl_error_chain_kind, impl_error_chain_processed,
+    impl_extract_backtrace,
+};
+
+error_chain! {
+   links  { }
+
+   errors {
+    SlotClockError(e: slot_clock::SystemTimeSlotClockError) {
+        description("Error reading system time"),
+        display("SlotClockError: '{:?}'", e)
+    }
+
+    SystemTimeError(t: String ) {
+        description("Error reading system time"),
+        display("SystemTimeError: '{}'", t)
+    }
+   }
+}

validator_client/src/lib.rs

@@ -0,0 +1,3 @@
+pub mod config;
+
+pub use crate::config::Config;

validator_client/src/main.rs

@@ -1,21 +1,14 @@
-use self::block_producer_service::{BeaconBlockGrpcClient, BlockProducerService};
-use self::duties::{DutiesManager, DutiesManagerService, EpochDutiesMap};
-use crate::config::ClientConfig;
-use block_proposer::{test_utils::LocalSigner, BlockProducer};
-use bls::Keypair;
-use clap::{App, Arg};
-use grpcio::{ChannelBuilder, EnvBuilder};
-use protos::services_grpc::{BeaconBlockServiceClient, ValidatorServiceClient};
-use slog::{error, info, o, Drain};
-use slot_clock::SystemTimeSlotClock;
-use std::path::PathBuf;
-use std::sync::Arc;
-use std::thread;
-use types::ChainSpec;
-
+mod attester_service;
 mod block_producer_service;
 mod config;
 mod duties;
+pub mod error;
+mod service;
+
+use crate::config::Config as ValidatorClientConfig;
+use clap::{App, Arg};
+use service::Service as ValidatorService;
+use slog::{error, info, o, Drain};
 
 fn main() {
     // Logging
@@ -55,136 +48,12 @@ fn main() {
         )
         .get_matches();
 
-    let mut config = ClientConfig::default();
+    let config = ValidatorClientConfig::parse_args(&matches, &log)
+        .expect("Unable to build a configuration for the validator client.");
 
-    // Custom datadir
-    if let Some(dir) = matches.value_of("datadir") {
-        config.data_dir = PathBuf::from(dir.to_string());
-    }
-
-    // Custom server port
-    if let Some(server_str) = matches.value_of("server") {
-        if let Ok(addr) = server_str.parse::<u16>() {
-            config.server = addr.to_string();
-        } else {
-            error!(log, "Invalid address"; "server" => server_str);
-            return;
-        }
-    }
-
-    // TODO: Permit loading a custom spec from file.
-    // Custom spec
-    if let Some(spec_str) = matches.value_of("spec") {
-        match spec_str {
-            "foundation" => config.spec = ChainSpec::foundation(),
-            "few_validators" => config.spec = ChainSpec::few_validators(),
-            // Should be impossible due to clap's `possible_values(..)` function.
-            _ => unreachable!(),
-        };
-    }
-
-    // Log configuration
-    info!(log, "";
-          "data_dir" => &config.data_dir.to_str(),
-          "server" => &config.server);
-
-    // Beacon node gRPC beacon block endpoints.
-    let beacon_block_grpc_client = {
-        let env = Arc::new(EnvBuilder::new().build());
-        let ch = ChannelBuilder::new(env).connect(&config.server);
-        Arc::new(BeaconBlockServiceClient::new(ch))
-    };
-
-    // Beacon node gRPC validator endpoints.
-    let validator_grpc_client = {
-        let env = Arc::new(EnvBuilder::new().build());
-        let ch = ChannelBuilder::new(env).connect(&config.server);
-        Arc::new(ValidatorServiceClient::new(ch))
-    };
-
-    // Spec
-    let spec = Arc::new(config.spec.clone());
-
-    // Clock for determining the present slot.
-    // TODO: this shouldn't be a static time, instead it should be pulled from the beacon node.
-    // https://github.com/sigp/lighthouse/issues/160
-    let genesis_time = 1_549_935_547;
-    let slot_clock = {
-        info!(log, "Genesis time"; "unix_epoch_seconds" => genesis_time);
-        let clock = SystemTimeSlotClock::new(genesis_time, spec.seconds_per_slot)
-            .expect("Unable to instantiate SystemTimeSlotClock.");
-        Arc::new(clock)
-    };
-
-    let poll_interval_millis = spec.seconds_per_slot * 1000 / 10; // 10% epoch time precision.
-    info!(log, "Starting block producer service"; "polls_per_epoch" => spec.seconds_per_slot * 1000 / poll_interval_millis);
-
-    /*
-     * Start threads.
-     */
-    let mut threads = vec![];
-    // TODO: keypairs are randomly generated; they should be loaded from a file or generated.
-    // https://github.com/sigp/lighthouse/issues/160
-    let keypairs = vec![Keypair::random()];
-
-    for keypair in keypairs {
-        info!(log, "Starting validator services"; "validator" => keypair.pk.concatenated_hex_id());
-        let duties_map = Arc::new(EpochDutiesMap::new(spec.slots_per_epoch));
-
-        // Spawn a new thread to maintain the validator's `EpochDuties`.
-        let duties_manager_thread = {
-            let spec = spec.clone();
-            let duties_map = duties_map.clone();
-            let slot_clock = slot_clock.clone();
-            let log = log.clone();
-            let beacon_node = validator_grpc_client.clone();
-            let pubkey = keypair.pk.clone();
-            thread::spawn(move || {
-                let manager = DutiesManager {
-                    duties_map,
-                    pubkey,
-                    spec,
-                    slot_clock,
-                    beacon_node,
-                };
-                let mut duties_manager_service = DutiesManagerService {
-                    manager,
-                    poll_interval_millis,
-                    log,
-                };
-
-                duties_manager_service.run();
-            })
-        };
-
-        // Spawn a new thread to perform block production for the validator.
-        let producer_thread = {
-            let spec = spec.clone();
-            let signer = Arc::new(LocalSigner::new(keypair.clone()));
-            let duties_map = duties_map.clone();
-            let slot_clock = slot_clock.clone();
-            let log = log.clone();
-            let client = Arc::new(BeaconBlockGrpcClient::new(beacon_block_grpc_client.clone()));
-            thread::spawn(move || {
-                let block_producer =
-                    BlockProducer::new(spec, duties_map, slot_clock, client, signer);
-                let mut block_producer_service = BlockProducerService {
-                    block_producer,
-                    poll_interval_millis,
-                    log,
-                };
-
-                block_producer_service.run();
-            })
-        };
-
-        threads.push((duties_manager_thread, producer_thread));
-    }
-
-    // Naively wait for all the threads to complete.
-    for tuple in threads {
-        let (manager, producer) = tuple;
-        let _ = producer.join();
-        let _ = manager.join();
+    // start the validator service.
+    match ValidatorService::start(config, log.clone()) {
+        Ok(_) => info!(log, "Validator client shutdown successfully."),
+        Err(e) => error!(log, "Validator exited due to: {}", e.to_string()),
     }
 }

validator_client/src/service.rs

@@ -0,0 +1,364 @@
+/// The validator service. Connects to a beacon node and signs blocks when required.
+use crate::attester_service::{AttestationGrpcClient, AttesterService};
+use crate::block_producer_service::{BeaconBlockGrpcClient, BlockProducerService};
+use crate::config::Config as ValidatorConfig;
+use crate::duties::UpdateOutcome;
+use crate::duties::{DutiesManager, EpochDutiesMap};
+use crate::error as error_chain;
+use crate::error::ErrorKind;
+use attester::test_utils::EpochMap;
+use attester::{test_utils::LocalSigner as AttesterLocalSigner, Attester};
+use block_proposer::{test_utils::LocalSigner as BlockProposerLocalSigner, BlockProducer};
+use bls::Keypair;
+use grpcio::{ChannelBuilder, EnvBuilder};
+use protos::services::Empty;
+use protos::services_grpc::{
+    AttestationServiceClient, BeaconBlockServiceClient, BeaconNodeServiceClient,
+    ValidatorServiceClient,
+};
+use slog::{debug, error, info, warn};
+use slot_clock::{SlotClock, SystemTimeSlotClock};
+use std::sync::Arc;
+use std::time::{Duration, Instant, SystemTime};
+use tokio::prelude::*;
+use tokio::runtime::Builder;
+use tokio::timer::Interval;
+use tokio_timer::clock::Clock;
+use types::{Epoch, Fork, Slot};
+
+//TODO: This service should be simplified in the future. Can be made more steamlined.
+
+/// The validator service. This is the main thread that executes and maintains validator
+/// duties.
+pub struct Service {
+    /// The node we currently connected to.
+    connected_node_version: String,
+    /// The chain id we are processing on.
+    chain_id: u16,
+    /// The fork state we processing on.
+    fork: Fork,
+    /// The slot clock keeping track of time.
+    slot_clock: Arc<SystemTimeSlotClock>,
+    /// The current slot we are processing.
+    current_slot: Slot,
+    /// Duration until the next slot. This is used for initializing the tokio timer interval.
+    duration_to_next_slot: Duration,
+    // GRPC Clients
+    /// The beacon block GRPC client.
+    beacon_block_client: Arc<BeaconBlockServiceClient>,
+    /// The validator GRPC client.
+    validator_client: Arc<ValidatorServiceClient>,
+    /// The attester GRPC client.
+    attester_client: Arc<AttestationServiceClient>,
+    /// The validator client logger.
+    log: slog::Logger,
+}
+
+impl Service {
+    ///  Initial connection to the beacon node to determine its properties.
+    ///
+    ///  This tries to connect to a beacon node. Once connected, it initialised the gRPC clients
+    ///  and returns an instance of the service.
+    fn initialize_service(
+        config: &ValidatorConfig,
+        log: slog::Logger,
+    ) -> error_chain::Result<Self> {
+        // initialise the beacon node client to check for a connection
+
+        let env = Arc::new(EnvBuilder::new().build());
+        // Beacon node gRPC beacon node endpoints.
+        let beacon_node_client = {
+            let ch = ChannelBuilder::new(env.clone()).connect(&config.server);
+            Arc::new(BeaconNodeServiceClient::new(ch))
+        };
+
+        // retrieve node information
+        let node_info = loop {
+            let info = match beacon_node_client.info(&Empty::new()) {
+                Err(e) => {
+                    warn!(log, "Could not connect to node. Error: {}", e);
+                    info!(log, "Retrying in 5 seconds...");
+                    std::thread::sleep(Duration::from_secs(5));
+                    continue;
+                }
+                Ok(info) => {
+                    if SystemTime::now()
+                        .duration_since(SystemTime::UNIX_EPOCH)
+                        .unwrap()
+                        .as_secs()
+                        < info.genesis_time
+                    {
+                        warn!(
+                            log,
+                            "Beacon Node's genesis time is in the future. No work to do.\n Exiting"
+                        );
+                        return Err("Genesis time in the future".into());
+                    }
+                    break info;
+                }
+            };
+        };
+
+        // build requisite objects to form Self
+        let genesis_time = node_info.get_genesis_time();
+
+        info!(log,"Beacon node connected"; "Node Version" => node_info.version.clone(), "Chain ID" => node_info.chain_id, "Genesis time" => genesis_time);
+
+        let proto_fork = node_info.get_fork();
+        let mut previous_version: [u8; 4] = [0; 4];
+        let mut current_version: [u8; 4] = [0; 4];
+        previous_version.copy_from_slice(&proto_fork.get_previous_version()[..4]);
+        current_version.copy_from_slice(&proto_fork.get_current_version()[..4]);
+        let fork = Fork {
+            previous_version,
+            current_version,
+            epoch: Epoch::from(proto_fork.get_epoch()),
+        };
+
+        // build the validator slot clock
+        let slot_clock = {
+            let clock = SystemTimeSlotClock::new(genesis_time, config.spec.seconds_per_slot)
+                .expect("Unable to instantiate SystemTimeSlotClock.");
+            Arc::new(clock)
+        };
+
+        // initialize the RPC clients
+
+        // Beacon node gRPC beacon block endpoints.
+        let beacon_block_client = {
+            let ch = ChannelBuilder::new(env.clone()).connect(&config.server);
+            Arc::new(BeaconBlockServiceClient::new(ch))
+        };
+
+        // Beacon node gRPC validator endpoints.
+        let validator_client = {
+            let ch = ChannelBuilder::new(env.clone()).connect(&config.server);
+            Arc::new(ValidatorServiceClient::new(ch))
+        };
+
+        //Beacon node gRPC attester endpoints.
+        let attester_client = {
+            let ch = ChannelBuilder::new(env.clone()).connect(&config.server);
+            Arc::new(AttestationServiceClient::new(ch))
+        };
+
+        let current_slot = slot_clock
+            .present_slot()
+            .map_err(|e| ErrorKind::SlotClockError(e))?
+            .expect("Genesis must be in the future");
+
+        // calculate the duration to the next slot
+        let duration_to_next_slot = {
+            let seconds_per_slot = config.spec.seconds_per_slot;
+            let syslot_time = SystemTime::now();
+            let duration_since_epoch = syslot_time
+                .duration_since(SystemTime::UNIX_EPOCH)
+                .map_err(|e| ErrorKind::SystemTimeError(e.to_string()))?;
+            let duration_since_genesis = duration_since_epoch
+                .checked_sub(Duration::from_secs(genesis_time))
+                .expect("Genesis must be in the future. Checked on connection");
+            let elapsed_slots = duration_since_epoch
+                .as_secs()
+                .checked_div(seconds_per_slot as u64)
+                .expect("Seconds per slot should not be 0");
+
+            // the duration to the next slot
+            Duration::from_secs(
+                (elapsed_slots + 1)
+                    .checked_mul(seconds_per_slot)
+                    .expect("Next slot time should not overflow u64"),
+            )
+            .checked_sub(duration_since_genesis)
+            .expect("This should never saturate")
+        };
+
+        Ok(Self {
+            connected_node_version: node_info.version,
+            chain_id: node_info.chain_id as u16,
+            fork,
+            slot_clock,
+            current_slot,
+            duration_to_next_slot,
+            beacon_block_client,
+            validator_client,
+            attester_client,
+            log,
+        })
+    }
+
+    /// Initialise the service then run the core thread.
+    pub fn start(config: ValidatorConfig, log: slog::Logger) -> error_chain::Result<()> {
+        // connect to the node and retrieve its properties and initialize the gRPC clients
+        let service = Service::initialize_service(&config, log)?;
+
+        // we have connected to a node and established its parameters. Spin up the core service
+
+        // set up the validator service runtime
+        let mut runtime = Builder::new()
+            .clock(Clock::system())
+            .name_prefix("validator-client-")
+            .build()
+            .map_err(|e| format!("Tokio runtime failed: {}", e))?;
+
+        // set up the validator work interval - start at next slot and proceed every slot
+        let interval = {
+            // Set the interval to start at the next slot, and every slot after
+            let slot_duration = Duration::from_secs(config.spec.seconds_per_slot);
+            //TODO: Handle checked add correctly
+            Interval::new(
+                Instant::now() + service.duration_to_next_slot,
+                slot_duration,
+            )
+        };
+
+        // kick off core service
+
+        // generate keypairs
+
+        // TODO: keypairs are randomly generated; they should be loaded from a file or generated.
+        // https://github.com/sigp/lighthouse/issues/160
+        let keypairs = Arc::new(vec![Keypair::random()]);
+
+        // build requisite objects to pass to core thread.
+        let duties_map = Arc::new(EpochDutiesMap::new(config.spec.slots_per_epoch));
+        let epoch_map_for_attester = Arc::new(EpochMap::new(config.spec.slots_per_epoch));
+        let manager = DutiesManager {
+            duties_map,
+            pubkeys: keypairs.iter().map(|keypair| keypair.pk.clone()).collect(),
+            spec: Arc::new(config.spec),
+            slot_clock: service.slot_clock.clone(),
+            beacon_node: service.validator_client.clone(),
+        };
+
+        // run the core thread
+        runtime
+            .block_on(interval.for_each(move |_| {
+                // get the current slot
+                let current_slot = match service.slot_clock.present_slot() {
+                    Err(e) => {
+                        error!(service.log, "SystemTimeError {:?}", e);
+                        return Ok(());
+                    }
+                    Ok(slot) => slot.expect("Genesis is in the future"),
+                };
+
+                debug_assert!(
+                    current_slot > service.current_slot,
+                    "The Timer should poll a new slot"
+                );
+
+                info!(service.log, "Processing slot: {}", current_slot.as_u64());
+
+                // check for new duties
+                // TODO: Convert to its own thread
+                match manager.update(current_slot) {
+                    Err(error) => {
+                        error!(service.log, "Epoch duties poll error"; "error" => format!("{:?}", error))
+                    }
+                    Ok(UpdateOutcome::NoChange(epoch)) => {
+                        debug!(service.log, "No change in duties"; "epoch" => epoch)
+                    }
+                    Ok(UpdateOutcome::DutiesChanged(epoch, duties)) => {
+                        info!(service.log, "Duties changed (potential re-org)"; "epoch" => epoch, "duties" => format!("{:?}", duties))
+                    }
+                    Ok(UpdateOutcome::NewDuties(epoch, duties)) => {
+                        info!(service.log, "New duties obtained"; "epoch" => epoch, "duties" => format!("{:?}", duties))
+                    }
+                    Ok(UpdateOutcome::UnknownValidatorOrEpoch(epoch)) => {
+                        error!(service.log, "Epoch or validator unknown"; "epoch" => epoch)
+                    }
+                };
+
+                Ok(())
+            }))
+            .map_err(|e| format!("Service thread failed: {:?}", e))?;
+        Ok(())
+    }
+
+    /*
+
+    let duties_map = Arc::new(EpochDutiesMap::new(spec.slots_per_epoch));
+    let epoch_map_for_attester = Arc::new(EpochMap::new(spec.slots_per_epoch));
+
+
+    for keypair in keypairs {
+        info!(self.log, "Starting validator services"; "validator" => keypair.pk.concatenated_hex_id());
+
+        // Spawn a new thread to maintain the validator's `EpochDuties`.
+        let duties_manager_thread = {
+            let spec = spec.clone();
+            let duties_map = duties_map.clone();
+            let slot_clock = self.slot_clock.clone();
+            let log = self.log.clone();
+            let beacon_node = self.validator_client.clone();
+            let pubkey = keypair.pk.clone();
+            thread::spawn(move || {
+                let manager = DutiesManager {
+                    duties_map,
+                    pubkey,
+                    spec,
+                    slot_clock,
+                    beacon_node,
+                };
+                let mut duties_manager_service = DutiesManagerService {
+                    manager,
+                    poll_interval_millis,
+                    log,
+                };
+
+                duties_manager_service.run();
+            })
+        };
+
+        // Spawn a new thread to perform block production for the validator.
+        let producer_thread = {
+            let spec = spec.clone();
+            let signer = Arc::new(BlockProposerLocalSigner::new(keypair.clone()));
+            let duties_map = duties_map.clone();
+            let slot_clock = slot_clock.clone();
+            let log = log.clone();
+            let client = Arc::new(BeaconBlockGrpcClient::new(beacon_block_grpc_client.clone()));
+            thread::spawn(move || {
+                let block_producer =
+                    BlockProducer::new(spec, duties_map, slot_clock, client, signer);
+                let mut block_producer_service = BlockProducerService {
+                    block_producer,
+                    poll_interval_millis,
+                    log,
+                };
+
+                block_producer_service.run();
+            })
+        };
+
+        // Spawn a new thread for attestation for the validator.
+        let attester_thread = {
+            let signer = Arc::new(AttesterLocalSigner::new(keypair.clone()));
+            let epoch_map = epoch_map_for_attester.clone();
+            let slot_clock = slot_clock.clone();
+            let log = log.clone();
+            let client = Arc::new(AttestationGrpcClient::new(attester_grpc_client.clone()));
+            thread::spawn(move || {
+                let attester = Attester::new(epoch_map, slot_clock, client, signer);
+                let mut attester_service = AttesterService {
+                    attester,
+                    poll_interval_millis,
+                    log,
+                };
+
+                attester_service.run();
+            })
+        };
+
+        threads.push((duties_manager_thread, producer_thread, attester_thread));
+    }
+
+    // Naively wait for all the threads to complete.
+    for tuple in threads {
+        let (manager, producer, attester) = tuple;
+        let _ = producer.join();
+        let _ = manager.join();
+        let _ = attester.join();
+    }
+    */
+}