|
| 1 | +from contextlib import contextmanager |
| 2 | +import logging |
| 3 | +from pathlib import Path |
| 4 | +from typing import ( |
| 5 | + Iterator, |
| 6 | + TYPE_CHECKING, |
| 7 | +) |
| 8 | + |
| 9 | +from eth_utils import ValidationError |
| 10 | + |
| 11 | +from eth.db.diff import ( |
| 12 | + DBDiffTracker, |
| 13 | + DiffMissingError, |
| 14 | +) |
| 15 | +from .base import ( |
| 16 | + BaseAtomicDB, |
| 17 | + BaseDB, |
| 18 | +) |
| 19 | + |
| 20 | +if TYPE_CHECKING: |
| 21 | + import rocksdb # noqa: F401 |
| 22 | + |
| 23 | + |
| 24 | +class RocksDB(BaseAtomicDB): |
| 25 | + logger = logging.getLogger("eth.db.backends.RocksDB") |
| 26 | + |
| 27 | + def __init__(self, |
| 28 | + db_path: Path = None, |
| 29 | + opts: 'rocksdb.Options' = None, |
| 30 | + read_only: bool=False) -> None: |
| 31 | + if not db_path: |
| 32 | + raise TypeError("The RocksDB backend requires a database path") |
| 33 | + try: |
| 34 | + import rocksdb # noqa: F811 |
| 35 | + except ImportError: |
| 36 | + raise ImportError( |
| 37 | + "RocksDB requires the python-rocksdb library which is not " |
| 38 | + "available for import." |
| 39 | + ) |
| 40 | + |
| 41 | + if opts is None: |
| 42 | + opts = rocksdb.Options(create_if_missing=True) |
| 43 | + self.db_path = db_path |
| 44 | + self.db = rocksdb.DB(str(db_path), opts, read_only=read_only) |
| 45 | + |
| 46 | + def __getitem__(self, key: bytes) -> bytes: |
| 47 | + v = self.db.get(key) |
| 48 | + if v is None: |
| 49 | + raise KeyError(key) |
| 50 | + return v |
| 51 | + |
| 52 | + def __setitem__(self, key: bytes, value: bytes) -> None: |
| 53 | + self.db.put(key, value) |
| 54 | + |
| 55 | + def _exists(self, key: bytes) -> bool: |
| 56 | + return self.db.get(key) is not None |
| 57 | + |
| 58 | + def __delitem__(self, key: bytes) -> None: |
| 59 | + exists, _ = self.db.key_may_exist(key) |
| 60 | + if not exists: |
| 61 | + raise KeyError(key) |
| 62 | + self.db.delete(key) |
| 63 | + |
| 64 | + @contextmanager |
| 65 | + def atomic_batch(self) -> Iterator['RocksDBWriteBatch']: |
| 66 | + import rocksdb # noqa: F811 |
| 67 | + batch = rocksdb.WriteBatch() |
| 68 | + |
| 69 | + readable_batch = RocksDBWriteBatch(self, batch) |
| 70 | + |
| 71 | + try: |
| 72 | + yield readable_batch |
| 73 | + finally: |
| 74 | + readable_batch.decommission() |
| 75 | + |
| 76 | + self.db.write(batch) |
| 77 | + |
| 78 | + |
| 79 | +class RocksDBWriteBatch(BaseDB): |
| 80 | + """ |
| 81 | + A native rocksdb write batch does not permit reads on the in-progress data. |
| 82 | + This class fills that gap, by tracking the in-progress diff, and adding |
| 83 | + a read interface. |
| 84 | + """ |
| 85 | + logger = logging.getLogger("eth.db.backends.RocksDBWriteBatch") |
| 86 | + |
| 87 | + def __init__(self, original_read_db: BaseDB, write_batch: 'rocksdb.WriteBatch') -> None: |
| 88 | + self._original_read_db = original_read_db |
| 89 | + self._write_batch = write_batch |
| 90 | + # keep track of the temporary changes made |
| 91 | + self._track_diff = DBDiffTracker() |
| 92 | + |
| 93 | + def __getitem__(self, key: bytes) -> bytes: |
| 94 | + if self._track_diff is None: |
| 95 | + raise ValidationError("Cannot get data from a write batch, out of context") |
| 96 | + |
| 97 | + try: |
| 98 | + changed_value = self._track_diff[key] |
| 99 | + except DiffMissingError as missing: |
| 100 | + if missing.is_deleted: |
| 101 | + raise KeyError(key) |
| 102 | + else: |
| 103 | + return self._original_read_db[key] |
| 104 | + else: |
| 105 | + return changed_value |
| 106 | + |
| 107 | + def __setitem__(self, key: bytes, value: bytes) -> None: |
| 108 | + if self._track_diff is None: |
| 109 | + raise ValidationError("Cannot set data from a write batch, out of context") |
| 110 | + |
| 111 | + self._write_batch.put(key, value) |
| 112 | + self._track_diff[key] = value |
| 113 | + |
| 114 | + def _exists(self, key: bytes) -> bool: |
| 115 | + if self._track_diff is None: |
| 116 | + raise ValidationError("Cannot test data existance from a write batch, out of context") |
| 117 | + |
| 118 | + try: |
| 119 | + self._track_diff[key] |
| 120 | + except DiffMissingError as missing: |
| 121 | + if missing.is_deleted: |
| 122 | + return False |
| 123 | + else: |
| 124 | + return key in self._original_read_db |
| 125 | + else: |
| 126 | + return True |
| 127 | + |
| 128 | + def __delitem__(self, key: bytes) -> None: |
| 129 | + if self._track_diff is None: |
| 130 | + raise ValidationError("Cannot delete data from a write batch, out of context") |
| 131 | + |
| 132 | + self._write_batch.delete(key) |
| 133 | + del self._track_diff[key] |
| 134 | + |
| 135 | + def decommission(self) -> None: |
| 136 | + """ |
| 137 | + Prevent any further actions to be taken on this write batch, called after leaving context |
| 138 | + """ |
| 139 | + self._track_diff = None |
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