probabilistic-rs 0.6.4

Probabilistic data structures in Rust
Documentation 
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232

import pytest


class TestExpiringBloomFilterInMemory:
    def test_insert_and_contains(self, ebloom_filter):
        ebloom_filter.insert(b"temp")
        assert ebloom_filter.contains(b"temp") == True

    def test_insert_bulk(self, ebloom_filter):
        items = [b"a", b"b", b"c"]
        ebloom_filter.insert_bulk(items)
        results = ebloom_filter.contains_bulk(items)
        assert results == [True, True, True]

    def test_rotate_levels(self, ebloom_filter):
        ebloom_filter.insert(b"before_rotate")
        ebloom_filter.rotate_levels()
        # Data from previous level must still be visible
        assert ebloom_filter.contains(b"before_rotate") == True

    def test_insert_after_rotate(self, ebloom_filter):
        ebloom_filter.insert(b"level0")
        ebloom_filter.rotate_levels()
        ebloom_filter.insert(b"level1")
        assert ebloom_filter.contains(b"level0") == True
        assert ebloom_filter.contains(b"level1") == True

    def test_full_rotation_clears_oldest(self, ebloom_filter):
        """After rotating num_levels times, the oldest level is cleared."""
        num_levels = ebloom_filter.num_levels()  # 3
        ebloom_filter.insert(b"oldest")
        # Rotate enough times that the level holding "oldest" gets cleared
        for _ in range(num_levels):
            ebloom_filter.rotate_levels()
        assert ebloom_filter.contains(b"oldest") == False

    def test_clear(self, ebloom_filter):
        ebloom_filter.insert(b"test")
        assert ebloom_filter.contains(b"test") == True
        ebloom_filter.clear()
        assert ebloom_filter.contains(b"test") == False

    def test_stats(self, ebloom_filter):
        assert ebloom_filter.capacity_per_level() == 10_000
        assert ebloom_filter.target_fpr() == 0.01
        assert ebloom_filter.num_levels() == 3
        assert ebloom_filter.active_levels() == 3
        ebloom_filter.insert(b"x")
        assert ebloom_filter.total_insert_count() == 1

    def test_total_insert_count_across_levels(self, ebloom_filter):
        ebloom_filter.insert_bulk([b"a", b"b", b"c"])
        ebloom_filter.rotate_levels()
        ebloom_filter.insert_bulk([b"d", b"e"])
        assert ebloom_filter.total_insert_count() == 5


class TestExpiringBloomFilterPersistence:
    def test_create_and_load(self, temp_dir):
        from probabilistic_rs import ExpiringBloomFilter

        db_path = str(temp_dir / "ebloom.db")

        ebf = ExpiringBloomFilter.create(db_path, capacity_per_level=10_000)
        ebf.insert(b"data")
        ebf.save_snapshot()
        del ebf

        ebf2 = ExpiringBloomFilter.load(db_path)
        assert ebf2.contains(b"data") == True

    def test_snapshot_on_drop(self, temp_dir):
        """Drop without explicit save_snapshot() — final snapshot must fire."""
        from probabilistic_rs import ExpiringBloomFilter

        db_path = str(temp_dir / "drop.db")

        ebf = ExpiringBloomFilter.create(db_path, capacity_per_level=10_000)
        ebf.insert(b"saved_on_drop")
        del ebf  # no save_snapshot()

        ebf2 = ExpiringBloomFilter.load(db_path)
        assert ebf2.contains(b"saved_on_drop") == True

    def test_snapshot_config_applied(self, temp_dir):
        """create() accepts SnapshotConfig and persists correctly."""
        from probabilistic_rs import ExpiringBloomFilter, SnapshotConfig

        db_path = str(temp_dir / "cfg.db")
        snap = SnapshotConfig(auto_snapshot=False)

        ebf = ExpiringBloomFilter.create(db_path, capacity_per_level=10_000, snapshot=snap)
        ebf.insert(b"cfg_item")
        ebf.save_snapshot()
        del ebf

        ebf2 = ExpiringBloomFilter.load(db_path)
        assert ebf2.contains(b"cfg_item") == True

    def test_rotation_full_snapshot_survives_reload(self, temp_dir):
        """rotate_levels() writes a full snapshot — data survives without save_snapshot()."""
        from probabilistic_rs import ExpiringBloomFilter

        db_path = str(temp_dir / "rotation_snap.db")

        ebf = ExpiringBloomFilter.create(db_path, capacity_per_level=10_000)
        ebf.insert(b"before_rotate")
        ebf.rotate_levels()  # full snapshot written here
        del ebf  # no explicit save_snapshot()

        ebf2 = ExpiringBloomFilter.load(db_path)
        assert ebf2.contains(b"before_rotate") == True

    def test_persistence_with_rotation(self, temp_dir):
        """Data inserted before and after rotation both survive reload."""
        from probabilistic_rs import ExpiringBloomFilter

        db_path = str(temp_dir / "rotation.db")

        ebf = ExpiringBloomFilter.create(db_path, capacity_per_level=10_000)
        ebf.insert(b"before")
        ebf.rotate_levels()
        ebf.insert(b"after")
        ebf.save_snapshot()
        del ebf

        ebf2 = ExpiringBloomFilter.load(db_path)
        assert ebf2.contains(b"before") == True
        assert ebf2.contains(b"after") == True

    def test_multiple_rotations_all_levels_survive(self, temp_dir):
        """Insert into each level via rotation; all survive reload until wrapped."""
        from probabilistic_rs import ExpiringBloomFilter

        db_path = str(temp_dir / "multi_rotate.db")
        num_levels = 3

        ebf = ExpiringBloomFilter.create(
            db_path, capacity_per_level=10_000, num_levels=num_levels
        )
        # Insert one item per level
        for i in range(num_levels - 1):
            ebf.insert(f"level{i}".encode())
            ebf.rotate_levels()
        ebf.insert(f"level{num_levels - 1}".encode())
        ebf.save_snapshot()
        del ebf

        ebf2 = ExpiringBloomFilter.load(db_path)
        for i in range(num_levels):
            assert ebf2.contains(f"level{i}".encode()) == True

    def test_full_circular_wrap_clears_oldest(self, temp_dir):
        """After rotating num_levels times, the original oldest level is cleared."""
        from probabilistic_rs import ExpiringBloomFilter

        db_path = str(temp_dir / "wrap.db")
        num_levels = 3

        ebf = ExpiringBloomFilter.create(
            db_path, capacity_per_level=10_000, num_levels=num_levels
        )
        ebf.insert(b"oldest")
        # Rotate enough to cycle back and clear the level holding "oldest"
        for _ in range(num_levels):
            ebf.rotate_levels()
        assert ebf.contains(b"oldest") == False

        ebf.insert(b"newest")
        ebf.save_snapshot()
        del ebf

        ebf2 = ExpiringBloomFilter.load(db_path)
        assert ebf2.contains(b"oldest") == False
        assert ebf2.contains(b"newest") == True

    def test_insert_count_trigger(self, temp_dir):
        """Insert-count trigger snapshots dirty state without explicit call."""
        from probabilistic_rs import ExpiringBloomFilter, SnapshotConfig
        import time

        db_path = str(temp_dir / "count.db")
        snap = SnapshotConfig(auto_snapshot=True, interval_secs=9999, after_inserts=5)

        ebf = ExpiringBloomFilter.create(db_path, capacity_per_level=10_000, snapshot=snap)
        for i in range(10):
            ebf.insert(f"item{i}".encode())
        time.sleep(0.2)
        del ebf

        ebf2 = ExpiringBloomFilter.load(db_path)
        for i in range(10):
            assert ebf2.contains(f"item{i}".encode()) == True

    def test_load_nonexistent_raises(self, temp_dir):
        from probabilistic_rs import ExpiringBloomFilter

        with pytest.raises(Exception):
            ExpiringBloomFilter.load(str(temp_dir / "nonexistent.db"))

    def test_overwrite_existing_db(self, temp_dir):
        """create() on existing path removes old data."""
        from probabilistic_rs import ExpiringBloomFilter

        db_path = str(temp_dir / "overwrite.db")

        ebf = ExpiringBloomFilter.create(db_path, capacity_per_level=10_000)
        ebf.insert(b"old_data")
        ebf.save_snapshot()
        del ebf

        ebf2 = ExpiringBloomFilter.create(db_path, capacity_per_level=10_000)
        ebf2.save_snapshot()
        del ebf2

        ebf3 = ExpiringBloomFilter.load(db_path)
        assert ebf3.contains(b"old_data") == False

    def test_post_rotation_snapshot_survives_reload(self, temp_dir):
        """After rotation, dirty-chunk snapshot of new level survives reload."""
        from probabilistic_rs import ExpiringBloomFilter

        db_path = str(temp_dir / "post_rotate_snap.db")

        ebf = ExpiringBloomFilter.create(db_path, capacity_per_level=10_000)
        ebf.rotate_levels()
        ebf.insert(b"new_level_item")
        ebf.save_snapshot()
        del ebf

        ebf2 = ExpiringBloomFilter.load(db_path)
        assert ebf2.contains(b"new_level_item") == True