Merge pull request #25 from lbryio/multiget-transactions

use `multi_get` for fetching transactions

scribe/blockchain/service.py

@@ -181,7 +181,7 @@ class BlockchainProcessorService(BlockchainService):
                         self.log.warning("failed to get a mempool tx, reorg underway?")
                         return
             if current_mempool:
-                if bytes.fromhex(await self.daemon.getbestblockhash())[::-1] != self.coin.header_hash(self.db.headers[-1]):
+                if bytes.fromhex(await self.daemon.getbestblockhash())[::-1] != self.db.block_hashes[-1]:
                     return
             await self.run_in_thread(
                 update_mempool, self.db.prefix_db.unsafe_commit, self.db.prefix_db.mempool_tx, _to_put, current_mempool
@@ -1417,6 +1417,7 @@ class BlockchainProcessorService(BlockchainService):
 
         self.height = height
         self.db.headers.append(block.header)
+        self.db.block_hashes.append(self.env.coin.header_hash(block.header))
         self.tip = self.coin.header_hash(block.header)
 
         self.db.fs_height = self.height
@@ -1493,8 +1494,9 @@ class BlockchainProcessorService(BlockchainService):
         # Check and update self.tip
 
         self.db.tx_counts.pop()
-        reverted_block_hash = self.coin.header_hash(self.db.headers.pop())
-        self.tip = self.coin.header_hash(self.db.headers[-1])
+        self.db.headers.pop()
+        reverted_block_hash = self.db.block_hashes.pop()
+        self.tip = self.db.block_hashes[-1]
         if self.env.cache_all_tx_hashes:
             while len(self.db.total_transactions) > self.db.tx_counts[-1]:
                 self.db.tx_num_mapping.pop(self.db.total_transactions.pop())

scribe/db/db.py

@@ -78,6 +78,7 @@ class HubDB:
 
         self.tx_counts = None
         self.headers = None
+        self.block_hashes = None
         self.encoded_headers = LRUCacheWithMetrics(1 << 21, metric_name='encoded_headers', namespace='wallet_server')
         self.last_flush = time.time()
 
@@ -775,6 +776,18 @@ class HubDB:
         assert len(headers) - 1 == self.db_height, f"{len(headers)} vs {self.db_height}"
         self.headers = headers
 
+    async def _read_block_hashes(self):
+        def get_block_hashes():
+            return [
+                block_hash for block_hash in self.prefix_db.block_hash.iterate(
+                    start=(0, ), stop=(self.db_height + 1, ), include_key=False, fill_cache=False, deserialize_value=False
+                )
+            ]
+
+        block_hashes = await asyncio.get_event_loop().run_in_executor(self._executor, get_block_hashes)
+        assert len(block_hashes) == len(self.headers)
+        self.block_hashes = block_hashes
+
     async def _read_tx_hashes(self):
         def _read_tx_hashes():
             return list(self.prefix_db.tx_hash.iterate(start=(0,), stop=(self.db_tx_count + 1,), include_key=False, fill_cache=False, deserialize_value=False))
@@ -839,6 +852,7 @@ class HubDB:
     async def initialize_caches(self):
         await self._read_tx_counts()
         await self._read_headers()
+        await self._read_block_hashes()
         if self._cache_all_claim_txos:
             await self._read_claim_txos()
         if self._cache_all_tx_hashes:
@@ -976,51 +990,74 @@ class HubDB:
 
     async def get_transactions_and_merkles(self, tx_hashes: Iterable[str]):
         tx_infos = {}
-        for tx_hash in tx_hashes:
-            tx_infos[tx_hash] = await asyncio.get_event_loop().run_in_executor(
-                self._executor, self._get_transaction_and_merkle, tx_hash
-            )
-            await asyncio.sleep(0)
-        return tx_infos
+        needed = []
+        needed_confirmed = []
+        needed_mempool = []
+        run_in_executor = asyncio.get_event_loop().run_in_executor
 
-    def _get_transaction_and_merkle(self, tx_hash):
-        cached_tx = self._tx_and_merkle_cache.get(tx_hash)
-        if cached_tx:
-            tx, merkle = cached_tx
-        else:
-            tx_hash_bytes = bytes.fromhex(tx_hash)[::-1]
-            tx_num = self.prefix_db.tx_num.get(tx_hash_bytes)
-            tx = None
-            tx_height = -1
-            tx_num = None if not tx_num else tx_num.tx_num
-            if tx_num is not None:
-                if self._cache_all_claim_txos:
-                    fill_cache = tx_num in self.txo_to_claim and len(self.txo_to_claim[tx_num]) > 0
-                else:
-                    fill_cache = True
-                tx_height = bisect_right(self.tx_counts, tx_num)
-                tx = self.prefix_db.tx.get(tx_hash_bytes, fill_cache=fill_cache, deserialize_value=False)
-            if tx_height == -1:
-                merkle = {
-                    'block_height': -1
-                }
-                tx = self.prefix_db.mempool_tx.get(tx_hash_bytes, deserialize_value=False)
+        for tx_hash in tx_hashes:
+            cached_tx = self._tx_and_merkle_cache.get(tx_hash)
+            if cached_tx:
+                tx, merkle = cached_tx
+                tx_infos[tx_hash] = None if not tx else tx.hex(), merkle
             else:
+                tx_hash_bytes = bytes.fromhex(tx_hash)[::-1]
+                if self._cache_all_tx_hashes and tx_hash_bytes in self.tx_num_mapping:
+                    needed_confirmed.append((tx_hash_bytes, self.tx_num_mapping[tx_hash_bytes]))
+                else:
+                    needed.append(tx_hash_bytes)
+
+        if needed:
+            for tx_hash_bytes, v in zip(needed, await run_in_executor(
+                    self._executor, self.prefix_db.tx_num.multi_get, [(tx_hash,) for tx_hash in needed],
+                    True, True)):
+                tx_num = None if v is None else v.tx_num
+                if tx_num is not None:
+                    needed_confirmed.append((tx_hash_bytes, tx_num))
+                else:
+                    needed_mempool.append(tx_hash_bytes)
+                await asyncio.sleep(0)
+
+        if needed_confirmed:
+            needed_heights = set()
+            tx_heights_and_positions = defaultdict(list)
+            for (tx_hash_bytes, tx_num), tx in zip(needed_confirmed, await run_in_executor(
+                    self._executor, self.prefix_db.tx.multi_get, [(tx_hash,) for tx_hash, _ in needed_confirmed],
+                    True, False)):
+                tx_height = bisect_right(self.tx_counts, tx_num)
+                needed_heights.add(tx_height)
                 tx_pos = tx_num - self.tx_counts[tx_height - 1]
-                branch, root = self.merkle.branch_and_root(
-                    self.get_block_txs(tx_height), tx_pos
+                tx_heights_and_positions[tx_height].append((tx_hash_bytes, tx, tx_num, tx_pos))
+
+            sorted_heights = list(sorted(needed_heights))
+            block_txs = await run_in_executor(
+                self._executor, self.prefix_db.block_txs.multi_get, [(height,) for height in sorted_heights]
+            )
+            block_txs = {height: v.tx_hashes for height, v in zip(sorted_heights, block_txs)}
+            for tx_height, v in tx_heights_and_positions.items():
+                branches, root = self.merkle.branches_and_root(
+                    block_txs[tx_height], [tx_pos for (tx_hash_bytes, tx, tx_num, tx_pos) in v]
                 )
-                merkle = {
-                    'block_height': tx_height,
-                    'merkle': [
-                        hash_to_hex_str(_hash)
-                        for _hash in branch
-                    ],
-                    'pos': tx_pos
-                }
-            if tx_height > 0 and tx_height + 10 < self.db_height:
-                self._tx_and_merkle_cache[tx_hash] = tx, merkle
-        return None if not tx else tx.hex(), merkle
+                for (tx_hash_bytes, tx, tx_num, tx_pos) in v:
+                    merkle = {
+                        'block_height': tx_height,
+                        'merkle': [
+                            hash_to_hex_str(_hash)
+                            for _hash in branches[tx_pos]
+                        ],
+                        'pos': tx_pos
+                    }
+                    tx_infos[tx_hash_bytes[::-1].hex()] = None if not tx else tx.hex(), merkle
+                    if tx_height > 0 and tx_height + 10 < self.db_height:
+                        self._tx_and_merkle_cache[tx_hash_bytes[::-1].hex()] = tx, merkle
+                await asyncio.sleep(0)
+        if needed_mempool:
+            for tx_hash_bytes, tx in zip(needed_mempool, await run_in_executor(
+                    self._executor, self.prefix_db.mempool_tx.multi_get, [(tx_hash,) for tx_hash in needed_mempool],
+                    True, False)):
+                tx_infos[tx_hash_bytes[::-1].hex()] = None if not tx else tx.hex(), {'block_height': -1}
+                await asyncio.sleep(0)
+        return tx_infos
 
     async def fs_block_hashes(self, height, count):
         if height + count > len(self.headers):

scribe/db/interface.py

@@ -90,12 +90,9 @@ class PrefixRow(metaclass=PrefixRowType):
 
     def multi_get(self, key_args: typing.List[typing.Tuple], fill_cache=True, deserialize_value=True):
         packed_keys = {tuple(args): self.pack_key(*args) for args in key_args}
-        result = {
-            k[-1]: v for k, v in (
-                self._db.multi_get([(self._column_family, packed_keys[tuple(args)]) for args in key_args],
-                                   fill_cache=fill_cache) or {}
-            ).items()
-        }
+        db_result = self._db.multi_get([(self._column_family, packed_keys[tuple(args)]) for args in key_args],
+                                   fill_cache=fill_cache)
+        result = {k[-1]: v for k, v in (db_result or {}).items()}
 
         def handle_value(v):
             return None if v is None else v if not deserialize_value else self.unpack_value(v)

scribe/db/merkle.py

@@ -25,7 +25,7 @@
 # and warranty status of this software.
 
 """Merkle trees, branches, proofs and roots."""
-
+import typing
 from asyncio import Event
 from math import ceil, log
 
@@ -87,6 +87,26 @@ class Merkle:
 
         return branch, hashes[0]
 
+    @staticmethod
+    def branches_and_root(block_tx_hashes: typing.List[bytes], tx_positions: typing.List[int]):
+        block_tx_hashes = list(block_tx_hashes)
+        positions = list(tx_positions)
+        length = ceil(log(len(block_tx_hashes), 2))
+        branches = [[] for _ in range(len(tx_positions))]
+        for _ in range(length):
+            if len(block_tx_hashes) & 1:
+                h = block_tx_hashes[-1]
+                block_tx_hashes.append(h)
+            for idx, tx_position in enumerate(tx_positions):
+                h = block_tx_hashes[tx_position ^ 1]
+                branches[idx].append(h)
+                tx_positions[idx] >>= 1
+            block_tx_hashes = [
+                double_sha256(block_tx_hashes[n] + block_tx_hashes[n + 1]) for n in
+                range(0, len(block_tx_hashes), 2)
+            ]
+        return {tx_position: branch for tx_position, branch in zip(positions, branches)}, block_tx_hashes[0]
+
     @staticmethod
     def root(hashes, length=None):
         """Return the merkle root of a non-empty iterable of binary hashes."""

scribe/elasticsearch/service.py

@@ -231,7 +231,7 @@ class ElasticSyncService(BlockchainReaderService):
         self._advanced = True
 
     def unwind(self):
-        reverted_block_hash = self.db.coin.header_hash(self.db.headers[-1])
+        reverted_block_hash = self.db.block_hashes[-1]
         super().unwind()
         packed = self.db.prefix_db.undo.get(len(self.db.tx_counts), reverted_block_hash)
         touched_or_deleted = None

scribe/service.py

@@ -157,7 +157,9 @@ class BlockchainReaderService(BlockchainService):
                 self.db.total_transactions.append(tx_hash)
                 self.db.tx_num_mapping[tx_hash] = tx_count
             assert len(self.db.total_transactions) == tx_count, f"{len(self.db.total_transactions)} vs {tx_count}"
-        self.db.headers.append(self.db.prefix_db.header.get(height, deserialize_value=False))
+        header = self.db.prefix_db.header.get(height, deserialize_value=False)
+        self.db.headers.append(header)
+        self.db.block_hashes.append(self.env.coin.header_hash(header))
 
     def unwind(self):
         """
@@ -166,6 +168,7 @@ class BlockchainReaderService(BlockchainService):
         prev_count = self.db.tx_counts.pop()
         tx_count = self.db.tx_counts[-1]
         self.db.headers.pop()
+        self.db.block_hashes.pop()
         if self.db._cache_all_tx_hashes:
             for _ in range(prev_count - tx_count):
                 self.db.tx_num_mapping.pop(self.db.total_transactions.pop())