Restructure of validator client service and block producer

validator_client/src/duties/beacon_node_duties.rs

@@ -0,0 +1,20 @@
+use super::EpochDuties;
+use types::{Epoch, PublicKey};
+
+#[derive(Debug, PartialEq, Clone)]
+pub enum BeaconNodeDutiesError {
+    RemoteFailure(String),
+}
+
+/// Defines the methods required to obtain a validators shuffling from a Beacon Node.
+pub trait BeaconNodeDuties: Send + Sync {
+    /// Gets the duties for all validators.
+    ///
+    /// Returns a vector of EpochDuties for each validator public key. The entry will be None for
+    /// validators that are not activated.
+    fn request_duties(
+        &self,
+        epoch: Epoch,
+        pubkeys: &[PublicKey],
+    ) -> Result<EpochDuties, BeaconNodeDutiesError>;
+}