Renamed attestation -> attestation_data for fetch, but not publish, to acknowledge the difference in the spec. Also started implementing the gRPC get_attestation_data functionality in the BeaconNode.

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

@@ -50,7 +50,7 @@ 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(
+    fn produce_attestation_data(
         &self,
         _slot: Slot,
         shard: u64,

beacon_node/rpc/src/beacon_attester.rs

@@ -1,45 +1,66 @@
+use crate::beacon_chain::BeaconChain;
 use futures::Future;
-use grpcio::{RpcContext, UnarySink};
+use grpcio::{RpcContext, UnarySink, RpcStatus, RpcStatusCode};
 use protos::services::{
-    Attestation as AttestationProto, ProduceAttestation, ProduceAttestationResponse,
+    AttestationData as AttestationDataProto, ProduceAttestationData, ProduceAttestationDataResponse,
-    ProduceAttestationRequest, PublishAttestationResponse, PublishAttestationRequest,
+    ProduceAttestationDataRequest, PublishAttestationResponse, PublishAttestationRequest,
     PublishAttestation
 };
 use protos::services_grpc::BeaconBlockService;
-use slog::Logger;
+use slog::{Logger, info, warn, error};
 
 #[derive(Clone)]
 pub struct AttestationServiceInstance {
+    pub chain: Arc<BeaconChain>,
     pub log: Logger,
 }
 
 impl AttestationService for AttestationServiceInstance {
-    /// Produce a `BeaconBlock` for signing by a validator.
+    /// Produce the `AttestationData` for signing by a validator.
-    fn produce_attestation(
+    fn produce_attestation_data(
         &mut self,
         ctx: RpcContext,
-        req: ProduceAttestationRequest,
+        req: ProduceAttestationDataRequest,
-        sink: UnarySink<ProduceAttestationResponse>,
+        sink: UnarySink<ProduceAttestationDataResponse>,
     ) {
-        println!("producing attestation at slot {}", req.get_slot());
+        info!(&self.log, "Attempting to produce attestation at slot {}", req.get_slot());
 
-        // TODO: build a legit block.
+        // get the chain spec & state
-        let mut attestation = AttestationProto::new();
+        let spec = self.chain.get_spec();
-        attestation.set_slot(req.get_slot());
+        let state = self.chain.get_state();
-        // TODO Set the shard to something legit.
-        attestation.set_shard(0);
-        attestation.set_block_root(b"cats".to_vec());
 
-        let mut resp = ProduceAttestationResponse::new();
+        // Start by performing some checks
-        resp.set_attestation_data(attestation);
+        // Check that the the AttestionData is for the current slot (otherwise it will not be valid)
+        if req.get_slot() != state.slot {
+            let f = sink
+                .fail(RpcStatus::new(
+                    RpcStatusCode::OutOfRange,
+                    "AttestationData request for a slot that is not the current slot."
+                ))
+                .map_err(move |e| error!(&self.log, "Failed to reply with failure {:?}: {:?}", req, e));
+        }
+
+        // Then collect the data we need for the AttesatationData object
+        //let beacon_block_root = state.latest_block_roots.first().ok_or_else(|e| )
+
+        // And finally build the AttestationData object
+        let mut attestation_data = AttestationDataProto::new();
+        attestation_data.set_slot(state.slot.as_u64());
+        attestation_data.set_shard(spec.genesis_start_shard);
+        attestation_data.set_beacon_block_root(b"cats".to_vec());
+        //attestation_data.
+
+        let mut resp = ProduceAttestationDataResponse::new();
+        resp.set_attestation_data(attestation_data);
 
         let f = sink
             .success(resp)
-            .map_err(move |e| println!("failed to reply {:?}: {:?}", req, e));
+            .map_err(move |e| error!("Failed to reply with success {:?}: {:?}", req, e));
         ctx.spawn(f)
     }
 
-    /// Accept some fully-formed `BeaconBlock`, process and publish it.
+    /// Accept some fully-formed `FreeAttestation` from the validator,
+    /// store it, and aggregate it into an `Attestation`.
     fn publish_attestation(
         &mut self,
         ctx: RpcContext,

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(slot, shard)? {
+        let attestation_data = match self.beacon_node.produce_attestation_data(slot, shard)? {
             Some(attestation_data) => attestation_data,
             None => return Ok(PollOutcome::BeaconNodeUnableToProduceAttestation(slot)),
         };

eth2/attester/src/test_utils/simulated_beacon_node.rs

@@ -26,7 +26,7 @@ impl SimulatedBeaconNode {
 }
 
 impl BeaconNode for SimulatedBeaconNode {
-    fn produce_attestation(&self, slot: Slot, shard: u64) -> ProduceResult {
+    fn produce_attestation_data(&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(),

eth2/attester/src/traits.rs

@@ -14,7 +14,7 @@ pub enum PublishOutcome {
 
 /// Defines the methods required to produce and publish blocks on a Beacon Node.
 pub trait BeaconNode: Send + Sync {
-    fn produce_attestation(
+    fn produce_attestation_data(
         &self,
         slot: Slot,
         shard: u64,

protos/src/services.proto

@@ -33,7 +33,7 @@ service ValidatorService {
 
 /// Service that handles validator attestations
 service AttestationService {
-	rpc ProduceAttestation(ProduceAttestationRequest) returns (ProduceAttestationResponse);
+	rpc ProduceAttestation(ProduceAttestationDataRequest) returns (ProduceAttestationDataResponse);
 	rpc PublishAttestation(PublishAttestationRequest) returns (PublishAttestationResponse);
 }
 
@@ -138,13 +138,13 @@ message ProposeBlockSlotResponse {
  * Attestation Service Messages
  */
 
-message ProduceAttestationRequest {
+message ProduceAttestationDataRequest {
 	uint64 slot = 1;
 	uint64 shard = 2;
 }
 
-message ProduceAttestationResponse {
+message ProduceAttestationDataResponse {
-	Attestation attestation_data = 1;
+	AttestationData attestation_data = 1;
 }
 
 message PublishAttestationRequest {
@@ -162,7 +162,7 @@ message Crosslink {
 
 }
 
-message Attestation {
+message AttestationData {
 	uint64 slot = 1;
 	uint64 shard = 2;
 	bytes beacon_block_root = 3;
@@ -175,7 +175,7 @@ message Attestation {
 }
 
 message FreeAttestation {
-	Attestation attestation_data = 1;
+	AttestationData data = 1;
 	bytes signature = 2;
 	uint64 validator_index = 3;
 }

validator_client/src/attester_service/attestation_grpc_client.rs

@@ -2,7 +2,7 @@ use protos::services_grpc::AttestationServiceClient;
 use std::sync::Arc;
 
 use attester::{BeaconNode, BeaconNodeError, PublishOutcome};
-use protos::services::ProduceAttestationRequest;
+use protos::services::ProduceAttestationDataRequest;
 use types::{AttestationData, FreeAttestation, Slot};
 
 pub struct AttestationGrpcClient {
@@ -16,12 +16,12 @@ impl AttestationGrpcClient {
 }
 
 impl BeaconNode for AttestationGrpcClient {
-    fn produce_attestation(
+    fn produce_attestation_data(
         &self,
         slot: Slot,
         shard: u64,
     ) -> Result<Option<AttestationData>, BeaconNodeError> {
-        let mut req = ProduceAttestationRequest::new();
+        let mut req = ProduceAttestationDataRequest::new();
         req.set_slot(slot.as_u64());
         req.set_shard(shard);