Keep existing blocks when restoring a Snapshot (#8643)

* Rename db_restore => client

* First step: make it compile!

* Second step: working implementation!

* Refactoring

* Fix tests

* PR Grumbles

* PR Grumbles WIP

* Migrate ancient blocks interating backward

* Early return in block migration if snapshot is aborted

* Remove RwLock getter (PR Grumble I)

* Remove dependency on `Client`: only used Traits

* Add test for recovering aborted snapshot recovery

* Add test for migrating old blocks

* Fix build

* PR Grumble I

* PR Grumble II

* PR Grumble III

* PR Grumble IV

* PR Grumble V

* PR Grumble VI

* Fix one test

* Fix test

* PR Grumble

* PR Grumbles

* PR Grumbles II

* Fix tests

* Release RwLock earlier

* Revert Cargo.lock

* Update _update ancient block_ logic: set local in `commit`

* Update typo in ethcore/src/snapshot/service.rs

Co-Authored-By: ngotchac <ngotchac@gmail.com>

ethcore/src/client/client.rs

@@ -32,7 +32,7 @@ use kvdb::{DBValue, KeyValueDB, DBTransaction};
 // other
 use ethereum_types::{H256, Address, U256};
 use block::{IsBlock, LockedBlock, Drain, ClosedBlock, OpenBlock, enact_verified, SealedBlock};
-use blockchain::{BlockChain, BlockChainDB, BlockProvider, TreeRoute, ImportRoute, TransactionAddress, ExtrasInsert};
+use blockchain::{BlockReceipts, BlockChain, BlockChainDB, BlockProvider, TreeRoute, ImportRoute, TransactionAddress, ExtrasInsert};
 use client::ancient_import::AncientVerifier;
 use client::{
 	Nonce, Balance, ChainInfo, BlockInfo, CallContract, TransactionInfo,
@@ -66,7 +66,7 @@ use ethcore_miner::pool::VerifiedTransaction;
 use parking_lot::{Mutex, RwLock};
 use rand::OsRng;
 use receipt::{Receipt, LocalizedReceipt};
-use snapshot::{self, io as snapshot_io};
+use snapshot::{self, io as snapshot_io, SnapshotClient};
 use spec::Spec;
 use state_db::StateDB;
 use state::{self, State};
@@ -1005,6 +1005,16 @@ impl Client {
 		self.importer.miner.clone()
 	}
 
+	#[cfg(test)]
+	pub fn state_db(&self) -> ::parking_lot::RwLockReadGuard<StateDB> {
+		self.state_db.read()
+	}
+
+	#[cfg(test)]
+	pub fn chain(&self) -> Arc<BlockChain> {
+		self.chain.read().clone()
+	}
+
 	/// Replace io channel. Useful for testing.
 	pub fn set_io_channel(&self, io_channel: IoChannel<ClientIoMessage>) {
 		*self.io_channel.write() = io_channel;
@@ -1817,7 +1827,7 @@ impl BlockChainClient for Client {
 		Some(receipt)
 	}
 
-	fn block_receipts(&self, id: BlockId) -> Option<Vec<LocalizedReceipt>> {
+	fn localized_block_receipts(&self, id: BlockId) -> Option<Vec<LocalizedReceipt>> {
 		let hash = self.block_hash(id)?;
 
 		let chain = self.chain.read();
@@ -1860,8 +1870,8 @@ impl BlockChainClient for Client {
 		self.state_db.read().journal_db().state(hash)
 	}
 
-	fn encoded_block_receipts(&self, hash: &H256) -> Option<Bytes> {
-		self.chain.read().block_receipts(hash).map(|receipts| ::rlp::encode(&receipts))
+	fn block_receipts(&self, hash: &H256) -> Option<BlockReceipts> {
+		self.chain.read().block_receipts(hash)
 	}
 
 	fn queue_info(&self) -> BlockQueueInfo {
@@ -2406,6 +2416,8 @@ impl ProvingBlockChainClient for Client {
 	}
 }
 
+impl SnapshotClient for Client {}
+
 impl Drop for Client {
 	fn drop(&mut self) {
 		self.engine.stop();
@@ -2504,7 +2516,7 @@ mod tests {
 		use test_helpers::{generate_dummy_client_with_data};
 
 		let client = generate_dummy_client_with_data(2, 2, &[1.into(), 1.into()]);
-		let receipts = client.block_receipts(BlockId::Latest).unwrap();
+		let receipts = client.localized_block_receipts(BlockId::Latest).unwrap();
 
 		assert_eq!(receipts.len(), 2);
 		assert_eq!(receipts[0].transaction_index, 0);

ethcore/src/client/test_client.rs

@@ -686,7 +686,7 @@ impl BlockChainClient for TestBlockChainClient {
 		self.receipts.read().get(&id).cloned()
 	}
 
-	fn block_receipts(&self, _id: BlockId) -> Option<Vec<LocalizedReceipt>> {
+	fn localized_block_receipts(&self, _id: BlockId) -> Option<Vec<LocalizedReceipt>> {
 		Some(self.receipts.read().values().cloned().collect())
 	}
 
@@ -789,16 +789,14 @@ impl BlockChainClient for TestBlockChainClient {
 		None
 	}
 
-	fn encoded_block_receipts(&self, hash: &H256) -> Option<Bytes> {
+	fn block_receipts(&self, hash: &H256) -> Option<BlockReceipts> {
 		// starts with 'f' ?
 		if *hash > H256::from("f000000000000000000000000000000000000000000000000000000000000000") {
 			let receipt = BlockReceipts::new(vec![Receipt::new(
 				TransactionOutcome::StateRoot(H256::zero()),
 				U256::zero(),
 				vec![])]);
-			let mut rlp = RlpStream::new();
-			rlp.append(&receipt);
-			return Some(rlp.out());
+			return Some(receipt);
 		}
 		None
 	}

ethcore/src/client/traits.rs

@@ -20,7 +20,7 @@ use std::sync::Arc;
 use itertools::Itertools;
 
 use block::{OpenBlock, SealedBlock, ClosedBlock};
-use blockchain::TreeRoute;
+use blockchain::{BlockReceipts, TreeRoute};
 use client::Mode;
 use encoded;
 use vm::LastHashes;
@@ -282,7 +282,7 @@ pub trait BlockChainClient : Sync + Send + AccountData + BlockChain + CallContra
 	fn transaction_receipt(&self, id: TransactionId) -> Option<LocalizedReceipt>;
 
 	/// Get localized receipts for all transaction in given block.
-	fn block_receipts(&self, id: BlockId) -> Option<Vec<LocalizedReceipt>>;
+	fn localized_block_receipts(&self, id: BlockId) -> Option<Vec<LocalizedReceipt>>;
 
 	/// Get a tree route between `from` and `to`.
 	/// See `BlockChain::tree_route`.
@@ -294,8 +294,8 @@ pub trait BlockChainClient : Sync + Send + AccountData + BlockChain + CallContra
 	/// Get latest state node
 	fn state_data(&self, hash: &H256) -> Option<Bytes>;
 
-	/// Get raw block receipts data by block header hash.
-	fn encoded_block_receipts(&self, hash: &H256) -> Option<Bytes>;
+	/// Get block receipts data by block header hash.
+	fn block_receipts(&self, hash: &H256) -> Option<BlockReceipts>;
 
 	/// Get block queue information.
 	fn queue_info(&self) -> BlockQueueInfo;