Allow updating configuration of changes tries (#3201)

* DigestItem::ChangesTrieSignal

* introduce changes_trie::State

* introduce config activation block

* ChangesTrieSignal::as_new_configuration

* moved well_known_cache_keys to client

* extracted DbChangesTrieStorage to separate file

* change meaning of none in blockchain cache

* changes trie config (FULL) cache draft

* eliminating const ChangesTrieConfiguration

* delay pruning

* continue elimination

* do not prune CT config from cache

* removed redundant code

* fix some TODOs

* introduce ConfigurationRange

* use Configuration range in build

* build skewed digest

* remove debug print

* extracted surface iterator

* key_changes works with skewed digests

* fix client build

* add test for NeverPrune

* fix TODO

* fixed some TODOs

* more tests

* fixing TODOs

* fixed compilation

* update runtime version

* git rid of large tuple

* too long lines

* config_activation_block -> zero

* obsolete TODO

* removed unjustified expect

* update TODOs with issue number

* new CT pruning algorithm

fixed cache + multiple blocks finalization

track CT configuraiton on light clients

support CT configuration change revert

revert CT config test

new CT pruning algorithm

fixed cache + multiple blocks finalization

track CT configuraiton on light clients

support CT configuration change revert

revert CT config test

* BlockIdOrHeader isn't really required

* removed debug leftovers + some docs

* more docs

* more post-merge fixes

* more post-merge fixes

* revertes some unnecessary changes

* reverted unnecessary changes

* fix compilation + unnecessary changes

* (restart CI)

* fix cache update when finalizing multiple blocks

* fixed tests

* collect_extrinsics -> set_collect_extrinsics

* restore lost test

* do not calculate block number twice

* Update primitives/blockchain/src/error.rs

Co-Authored-By: cheme <emericchevalier.pro@gmail.com>

* map_err -> unwrap_or

* document get_at Result

* delete abandoned file

* added weight for set_changes_trie_config

* prefer_configs -> fail_if_disabled

* Update client/api/src/backend.rs

Co-Authored-By: cheme <emericchevalier.pro@gmail.com>

* Update client/db/src/changes_tries_storage.rs

Co-Authored-By: cheme <emericchevalier.pro@gmail.com>

* CommitOperation+merge -> CommitOperations

* fixed test compilation

* merged two different CTRange structs

* lost file

* uggrade db from v0 to v1 (init CT cache + add column)

* fix after merge

Co-authored-by: cheme <emericchevalier.pro@gmail.com>
Co-authored-by: Gavin Wood <github@gavwood.com>

substrate/client/src/light/backend.rs

@@ -21,19 +21,22 @@ use std::collections::HashMap;
 use std::sync::Arc;
 use parking_lot::RwLock;
 
-use sp_core::storage::{ChildInfo, OwnedChildInfo};
+use codec::{Decode, Encode};
+
+use sp_core::ChangesTrieConfiguration;
+use sp_core::storage::{well_known_keys, ChildInfo, OwnedChildInfo};
 use sp_core::offchain::storage::InMemOffchainStorage;
 use sp_state_machine::{
 	Backend as StateBackend, TrieBackend, InMemoryBackend, ChangesTrieTransaction
 };
 use sp_runtime::{generic::BlockId, Justification, Storage};
 use sp_runtime::traits::{Block as BlockT, NumberFor, Zero, Header, HasherFor};
-use crate::in_mem::{self, check_genesis_storage};
+use crate::in_mem::check_genesis_storage;
 use sp_blockchain::{Error as ClientError, Result as ClientResult};
 use sc_client_api::{
 	backend::{
 		AuxStore, Backend as ClientBackend, BlockImportOperation, RemoteBackend, NewBlockState,
-		StorageCollection, ChildStorageCollection,
+		StorageCollection, ChildStorageCollection, PrunableStateChangesTrieStorage,
 	},
 	blockchain::{
 		HeaderBackend as BlockchainHeaderBackend, well_known_cache_keys,
@@ -62,6 +65,7 @@ pub struct ImportOperation<Block: BlockT, S> {
 	finalized_blocks: Vec<BlockId<Block>>,
 	set_head: Option<BlockId<Block>>,
 	storage_update: Option<InMemoryBackend<HasherFor<Block>>>,
+	changes_trie_config_update: Option<Option<ChangesTrieConfiguration>>,
 	_phantom: std::marker::PhantomData<S>,
 }
 
@@ -115,7 +119,6 @@ impl<S, Block> ClientBackend<Block> for Backend<S, HasherFor<Block>>
 	type BlockImportOperation = ImportOperation<Block, S>;
 	type Blockchain = Blockchain<S>;
 	type State = GenesisOrUnavailableState<HasherFor<Block>>;
-	type ChangesTrieStorage = in_mem::ChangesTrieStorage<Block>;
 	type OffchainStorage = InMemOffchainStorage;
 
 	fn begin_operation(&self) -> ClientResult<Self::BlockImportOperation> {
@@ -127,6 +130,7 @@ impl<S, Block> ClientBackend<Block> for Backend<S, HasherFor<Block>>
 			finalized_blocks: Vec::new(),
 			set_head: None,
 			storage_update: None,
+			changes_trie_config_update: None,
 			_phantom: Default::default(),
 		})
 	}
@@ -148,6 +152,9 @@ impl<S, Block> ClientBackend<Block> for Backend<S, HasherFor<Block>>
 
 		if let Some(header) = operation.header {
 			let is_genesis_import = header.number().is_zero();
+			if let Some(new_config) = operation.changes_trie_config_update {
+				operation.cache.insert(well_known_cache_keys::CHANGES_TRIE_CONFIG, new_config.encode());
+			}
 			self.blockchain.storage().import_header(
 				header,
 				operation.cache,
@@ -194,7 +201,7 @@ impl<S, Block> ClientBackend<Block> for Backend<S, HasherFor<Block>>
 		self.blockchain.storage().usage_info()
 	}
 
-	fn changes_trie_storage(&self) -> Option<&Self::ChangesTrieStorage> {
+	fn changes_trie_storage(&self) -> Option<&dyn PrunableStateChangesTrieStorage<Block>> {
 		None
 	}
 
@@ -296,6 +303,13 @@ impl<S, Block> BlockImportOperation<Block> for ImportOperation<Block, S>
 	fn reset_storage(&mut self, input: Storage) -> ClientResult<Block::Hash> {
 		check_genesis_storage(&input)?;
 
+		// changes trie configuration
+		let changes_trie_config = input.top.iter()
+			.find(|(k, _)| &k[..] == well_known_keys::CHANGES_TRIE_CONFIG)
+			.map(|(_, v)| Decode::decode(&mut &v[..])
+				.expect("changes trie configuration is encoded properly at genesis"));
+		self.changes_trie_config_update = Some(changes_trie_config);
+
 		// this is only called when genesis block is imported => shouldn't be performance bottleneck
 		let mut storage: HashMap<Option<(Vec<u8>, OwnedChildInfo)>, _> = HashMap::new();
 		storage.insert(None, input.top);

substrate/client/src/light/call_executor.rs

@@ -259,7 +259,7 @@ fn check_execution_proof_with_make_header<Header, E, H, MakeNextHeader: Fn(&Head
 	let mut changes = OverlayedChanges::default();
 	let trie_backend = create_proof_check_backend(root, remote_proof)?;
 	let next_header = make_next_header(&request.header);
-	execution_proof_check_on_trie_backend::<H, _>(
+	execution_proof_check_on_trie_backend::<H, Header::Number, _>(
 		&trie_backend,
 		&mut changes,
 		executor,
@@ -268,7 +268,7 @@ fn check_execution_proof_with_make_header<Header, E, H, MakeNextHeader: Fn(&Head
 	)?;
 
 	// execute method
-	execution_proof_check_on_trie_backend::<H, _>(
+	execution_proof_check_on_trie_backend::<H, Header::Number, _>(
 		&trie_backend,
 		&mut changes,
 		executor,

substrate/client/src/light/fetcher.rs

@@ -25,12 +25,12 @@ use codec::{Decode, Encode};
 use sp_core::{convert_hash, traits::CodeExecutor};
 use sp_runtime::traits::{
 	Block as BlockT, Header as HeaderT, Hash, HashFor, NumberFor,
-	SimpleArithmetic, CheckedConversion, Zero,
+	SimpleArithmetic, CheckedConversion,
 };
 use sp_state_machine::{
 	ChangesTrieRootsStorage, ChangesTrieAnchorBlockId, ChangesTrieConfigurationRange,
-	TrieBackend, read_proof_check, key_changes_proof_check, create_proof_check_backend_storage,
-	read_child_proof_check,
+	InMemoryChangesTrieStorage, TrieBackend, read_proof_check, key_changes_proof_check_with_db,
+	create_proof_check_backend_storage, read_child_proof_check,
 };
 pub use sp_state_machine::StorageProof;
 use sp_blockchain::{Error as ClientError, Result as ClientResult};
@@ -113,30 +113,34 @@ impl<E, H, B: BlockT, S: BlockchainStorage<B>> LightDataChecker<E, H, B, S> {
 			)?;
 		}
 
-		// FIXME: remove this in https://github.com/paritytech/substrate/pull/3201
-		let changes_trie_config_range = ChangesTrieConfigurationRange {
-			config: &request.changes_trie_config,
-			zero: Zero::zero(),
-			end: None,
-		};
-
 		// and now check the key changes proof + get the changes
-		key_changes_proof_check::<H, _>(
-			changes_trie_config_range,
-			&RootsStorage {
-				roots: (request.tries_roots.0, &request.tries_roots.2),
-				prev_roots: remote_roots,
-			},
-			remote_proof,
-			request.first_block.0,
-			&ChangesTrieAnchorBlockId {
-				hash: convert_hash(&request.last_block.1),
-				number: request.last_block.0,
-			},
-			remote_max_block,
-			request.storage_key.as_ref().map(Vec::as_slice),
-			&request.key)
-		.map_err(|err| ClientError::ChangesTrieAccessFailed(err))
+		let mut result = Vec::new();
+		let proof_storage = InMemoryChangesTrieStorage::with_proof(remote_proof);
+		for config_range in &request.changes_trie_configs {
+			let result_range = key_changes_proof_check_with_db::<H, _>(
+				ChangesTrieConfigurationRange {
+					config: config_range.config.as_ref().ok_or(ClientError::ChangesTriesNotSupported)?,
+					zero: config_range.zero.0,
+					end: config_range.end.map(|(n, _)| n),
+				},
+				&RootsStorage {
+					roots: (request.tries_roots.0, &request.tries_roots.2),
+					prev_roots: &remote_roots,
+				},
+				&proof_storage,
+				request.first_block.0,
+				&ChangesTrieAnchorBlockId {
+					hash: convert_hash(&request.last_block.1),
+					number: request.last_block.0,
+				},
+				remote_max_block,
+				request.storage_key.as_ref().map(Vec::as_slice),
+				&request.key)
+			.map_err(|err| ClientError::ChangesTrieAccessFailed(err))?;
+			result.extend(result_range);
+		}
+
+		Ok(result)
 	}
 
 	/// Check CHT-based proof for changes tries roots.
@@ -284,7 +288,7 @@ impl<E, Block, H, S> FetchChecker<Block> for LightDataChecker<E, H, Block, S>
 /// A view of BTreeMap<Number, Hash> as a changes trie roots storage.
 struct RootsStorage<'a, Number: SimpleArithmetic, Hash: 'a> {
 	roots: (Number, &'a [Hash]),
-	prev_roots: BTreeMap<Number, Hash>,
+	prev_roots: &'a BTreeMap<Number, Hash>,
 }
 
 impl<'a, H, Number, Hash> ChangesTrieRootsStorage<H, Number> for RootsStorage<'a, Number, Hash>
@@ -340,7 +344,7 @@ pub mod tests {
 	use crate::in_mem::{Blockchain as InMemoryBlockchain};
 	use crate::light::fetcher::{FetchChecker, LightDataChecker, RemoteHeaderRequest};
 	use crate::light::blockchain::tests::{DummyStorage, DummyBlockchain};
-	use sp_core::{blake2_256, Blake2Hasher, H256};
+	use sp_core::{blake2_256, Blake2Hasher, ChangesTrieConfiguration, H256};
 	use sp_core::storage::{well_known_keys, StorageKey, ChildInfo};
 	use sp_runtime::generic::BlockId;
 	use sp_state_machine::Backend;
@@ -569,8 +573,13 @@ pub mod tests {
 
 			// check proof on local client
 			let local_roots_range = local_roots.clone()[(begin - 1) as usize..].to_vec();
+			let config = ChangesTrieConfiguration::new(4, 2);
 			let request = RemoteChangesRequest::<Header> {
-				changes_trie_config: runtime::changes_trie_config(),
+				changes_trie_configs: vec![sp_core::ChangesTrieConfigurationRange {
+					zero: (0, Default::default()),
+					end: None,
+					config: Some(config),
+				}],
 				first_block: (begin, begin_hash),
 				last_block: (end, end_hash),
 				max_block: (max, max_hash),
@@ -624,8 +633,13 @@ pub mod tests {
 		);
 
 		// check proof on local client
+		let config = ChangesTrieConfiguration::new(4, 2);
 		let request = RemoteChangesRequest::<Header> {
-			changes_trie_config: runtime::changes_trie_config(),
+			changes_trie_configs: vec![sp_core::ChangesTrieConfigurationRange {
+				zero: (0, Default::default()),
+				end: None,
+				config: Some(config),
+			}],
 			first_block: (1, b1),
 			last_block: (4, b4),
 			max_block: (4, b4),
@@ -665,8 +679,13 @@ pub mod tests {
 			begin_hash, end_hash, begin_hash, max_hash, None, &key).unwrap();
 
 		let local_roots_range = local_roots.clone()[(begin - 1) as usize..].to_vec();
+		let config = ChangesTrieConfiguration::new(4, 2);
 		let request = RemoteChangesRequest::<Header> {
-			changes_trie_config: runtime::changes_trie_config(),
+			changes_trie_configs: vec![sp_core::ChangesTrieConfigurationRange {
+				zero: (0, Default::default()),
+				end: None,
+				config: Some(config),
+			}],
 			first_block: (begin, begin_hash),
 			last_block: (end, end_hash),
 			max_block: (max, max_hash),