Disabled validators runtime API

polkadot/node/subsystem-types/src/runtime_client.rs

@@ -240,7 +240,6 @@ pub trait RuntimeApiSubsystemClient {
 		session_index: SessionIndex,
 	) -> Result<u32, ApiError>;
 
-
 	// === v7: Asynchronous backing API ===
 
 	/// Returns candidate's acceptance limitations for asynchronous backing for a relay parent.

polkadot/runtime/parachains/src/runtime_api_impl/vstaging.rs

@@ -16,18 +16,28 @@
 
 //! Put implementations of functions from staging APIs here.
 
-use primitives::{
-	ValidatorIndex,
-};
-use sp_std::prelude::*;
+use crate::shared;
+use primitives::ValidatorIndex;
+use sp_std::prelude::Vec;
+use sp_std::collections::btree_map::BTreeMap;
 
 /// Implementation for `DisabledValidators`
-pub fn disabled_validators<T: pallet_session::Config>() -> Vec<ValidatorIndex> {
-	// <pallet_session::Pallet<T>>::disabled_validators()
-	// 	.iter()
-	// 	.cloned()
-	// 	.map(|v| ValidatorIndex(v))
-	// 	.collect()
-	// TODO
-	Vec::new()
+pub fn disabled_validators<T>() -> Vec<ValidatorIndex>
+where
+	T: pallet_session::Config + shared::Config,
+{
+	let shuffled_indices = <shared::Pallet<T>>::active_validator_indices();
+	// mapping from raw validator index to `ValidatorIndex`
+	// this computation is the same within a session, but should be cheap
+	let reverse_index = shuffled_indices
+		.iter()
+		.enumerate()
+		.map(|(i, v)| (v.0, ValidatorIndex(i as u32)))
+		.collect::<BTreeMap<u32, ValidatorIndex>>();
+
+	// we might have disabled validators who are not parachain validators
+	<pallet_session::Pallet<T>>::disabled_validators()
+		.iter()
+		.filter_map(|v| reverse_index.get(v).cloned())
+		.collect()
 }