Define type and modify function

common/eth2/src/types.rs

@@ -948,6 +948,13 @@ pub struct PeerCount {
     pub disconnecting: u64,
 }
 
+#[derive(Debug, Clone, PartialEq, Serialize, Deserialize)]
+pub struct BeaconCommitteeSelection {
+    #[serde(with = "serde_utils::quoted_u64")]
+    pub validator_index: u64,
+    pub slot: Slot,
+    pub selection_proof: Signature,
+}
 // --------- Server Sent Event Types -----------
 
 #[derive(PartialEq, Debug, Serialize, Deserialize, Clone)]

validator_client/validator_services/src/duties_service.rs

@@ -129,7 +129,21 @@ async fn make_selection_proof<T: SlotClock + 'static, E: EthSpec>(
     duty: &AttesterData,
     validator_store: &ValidatorStore<T, E>,
     spec: &ChainSpec,
+    distributed: bool,
+    beacon_nodes: &Arc<BeaconNodeFallback<T, E>>,
 ) -> Result<Option<SelectionProof>, Error> {
+    if distributed {
+        // call the middleware for the endpoint /eth/v1/validator/beacon_committee_subscriptions
+        beacon_nodes
+            .first_success(|beacon_node| async move {
+                beacon_node
+                    .post_validator_beacon_committee_subscriptions()
+                    .await
+            })
+            .await
+            .map_err(|e| Error::FailedToProduceSelectionProof(e.to_string()))
+            .map(|_| None)
+    } else {
         let selection_proof = validator_store
             .produce_selection_proof(duty.pubkey, duty.slot)
             .await
@@ -148,6 +162,7 @@ async fn make_selection_proof<T: SlotClock + 'static, E: EthSpec>(
                 }
             })
     }
+}
 
 impl DutyAndProof {
     /// Create a new `DutyAndProof` with the selection proof waiting to be filled in.
@@ -1101,6 +1116,8 @@ async fn fill_in_selection_proofs<T: SlotClock + 'static, E: EthSpec>(
                         &duty,
                         &duties_service.validator_store,
                         &duties_service.spec,
+                        duties_service.distributed,
+                        &duties_service.beacon_nodes,
                     )
                     .await?;
                     Ok((duty, opt_selection_proof))