Expose ClaimQueue via a runtime api and use it in collation-generation (#3580)

The PR adds two things:
1. Runtime API exposing the whole claim queue
2. Consumes the API in `collation-generation` to fetch the next
scheduled `ParaEntry` for an occupied core.

Related to https://github.com/paritytech/polkadot-sdk/issues/1797

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

@@ -45,7 +45,7 @@ use polkadot_primitives::{
 	async_backing, slashing,
 	vstaging::{ApprovalVotingParams, NodeFeatures},
 	AuthorityDiscoveryId, BackedCandidate, BlockNumber, CandidateEvent, CandidateHash,
-	CandidateIndex, CandidateReceipt, CollatorId, CommittedCandidateReceipt, CoreState,
+	CandidateIndex, CandidateReceipt, CollatorId, CommittedCandidateReceipt, CoreIndex, CoreState,
 	DisputeState, ExecutorParams, GroupIndex, GroupRotationInfo, Hash, HeadData,
 	Header as BlockHeader, Id as ParaId, InboundDownwardMessage, InboundHrmpMessage,
 	MultiDisputeStatementSet, OccupiedCoreAssumption, PersistedValidationData, PvfCheckStatement,
@@ -55,7 +55,7 @@ use polkadot_primitives::{
 };
 use polkadot_statement_table::v2::Misbehavior;
 use std::{
-	collections::{BTreeMap, HashMap, HashSet},
+	collections::{BTreeMap, HashMap, HashSet, VecDeque},
 	sync::Arc,
 };
 
@@ -729,6 +729,9 @@ pub enum RuntimeApiRequest {
 	/// Approval voting params
 	/// `V10`
 	ApprovalVotingParams(SessionIndex, RuntimeApiSender<ApprovalVotingParams>),
+	/// Fetch the `ClaimQueue` from scheduler pallet
+	/// `V11`
+	ClaimQueue(RuntimeApiSender<BTreeMap<CoreIndex, VecDeque<ParaId>>>),
 }
 
 impl RuntimeApiRequest {
@@ -763,6 +766,9 @@ impl RuntimeApiRequest {
 
 	/// `approval_voting_params`
 	pub const APPROVAL_VOTING_PARAMS_REQUIREMENT: u32 = 10;
+
+	/// `ClaimQueue`
+	pub const CLAIM_QUEUE_RUNTIME_REQUIREMENT: u32 = 11;
 }
 
 /// A message to the Runtime API subsystem.

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

@@ -21,10 +21,11 @@ use polkadot_primitives::{
 	slashing,
 	vstaging::{self, ApprovalVotingParams},
 	Block, BlockNumber, CandidateCommitments, CandidateEvent, CandidateHash,
-	CommittedCandidateReceipt, CoreState, DisputeState, ExecutorParams, GroupRotationInfo, Hash,
-	Header, Id, InboundDownwardMessage, InboundHrmpMessage, OccupiedCoreAssumption,
-	PersistedValidationData, PvfCheckStatement, ScrapedOnChainVotes, SessionIndex, SessionInfo,
-	ValidationCode, ValidationCodeHash, ValidatorId, ValidatorIndex, ValidatorSignature,
+	CommittedCandidateReceipt, CoreIndex, CoreState, DisputeState, ExecutorParams,
+	GroupRotationInfo, Hash, Header, Id, InboundDownwardMessage, InboundHrmpMessage,
+	OccupiedCoreAssumption, PersistedValidationData, PvfCheckStatement, ScrapedOnChainVotes,
+	SessionIndex, SessionInfo, ValidationCode, ValidationCodeHash, ValidatorId, ValidatorIndex,
+	ValidatorSignature,
 };
 use sc_client_api::{AuxStore, HeaderBackend};
 use sc_transaction_pool_api::OffchainTransactionPoolFactory;
@@ -33,7 +34,10 @@ use sp_authority_discovery::AuthorityDiscoveryApi;
 use sp_blockchain::{BlockStatus, Info};
 use sp_consensus_babe::{BabeApi, Epoch};
 use sp_runtime::traits::{Block as BlockT, Header as HeaderT, NumberFor};
-use std::{collections::BTreeMap, sync::Arc};
+use std::{
+	collections::{BTreeMap, VecDeque},
+	sync::Arc,
+};
 
 /// Offers header utilities.
 ///
@@ -329,6 +333,10 @@ pub trait RuntimeApiSubsystemClient {
 		at: Hash,
 		session_index: SessionIndex,
 	) -> Result<ApprovalVotingParams, ApiError>;
+
+	// == v11: Claim queue ==
+	/// Fetch the `ClaimQueue` from scheduler pallet
+	async fn claim_queue(&self, at: Hash) -> Result<BTreeMap<CoreIndex, VecDeque<Id>>, ApiError>;
 }
 
 /// Default implementation of [`RuntimeApiSubsystemClient`] using the client.
@@ -594,6 +602,10 @@ where
 	) -> Result<ApprovalVotingParams, ApiError> {
 		self.client.runtime_api().approval_voting_params(at)
 	}
+
+	async fn claim_queue(&self, at: Hash) -> Result<BTreeMap<CoreIndex, VecDeque<Id>>, ApiError> {
+		self.client.runtime_api().claim_queue(at)
+	}
 }
 
 impl<Client, Block> HeaderBackend<Block> for DefaultSubsystemClient<Client>