Add progress on test rig

beacon_node/beacon_chain/src/attestation_targets.rs

@@ -0,0 +1,50 @@
+use crate::{BeaconChain, CheckPoint, ClientDB, SlotClock};
+use std::collections::HashMap;
+use std::sync::RwLockReadGuard;
+use types::{BeaconBlock, BeaconState, Hash256};
+
+pub struct AttestationTargets {
+    map: HashMap<u64, Hash256>,
+}
+
+impl AttestationTargets {
+    pub fn new() -> Self {
+        Self {
+            map: HashMap::new(),
+        }
+    }
+
+    pub fn get(&self, validator_index: u64) -> Option<&Hash256> {
+        self.map.get(&validator_index)
+    }
+
+    pub fn insert(&mut self, validator_index: u64, block_hash: Hash256) -> Option<Hash256> {
+        self.map.insert(validator_index, block_hash)
+    }
+}
+
+impl<T, U> BeaconChain<T, U>
+where
+    T: ClientDB,
+    U: SlotClock,
+{
+    pub fn insert_latest_attestation_target(&self, validator_index: u64, block_root: Hash256) {
+        let mut targets = self
+            .latest_attestation_targets
+            .write()
+            .expect("CRITICAL: CanonicalHead poisioned.");
+        targets.insert(validator_index, block_root);
+    }
+
+    pub fn get_latest_attestation_target(&self, validator_index: u64) -> Option<Hash256> {
+        let targets = self
+            .latest_attestation_targets
+            .read()
+            .expect("CRITICAL: CanonicalHead poisioned.");
+
+        match targets.get(validator_index) {
+            Some(hash) => Some(hash.clone()),
+            None => None,
+        }
+    }
+}