Files
DECNET/decnet/vectorstore/sqlite_vec.py
anti f2b3393669 chore: relicense to AGPL-3.0-or-later and add SPDX headers
Replaces LICENSE (GPLv3 -> AGPLv3) and prepends
`SPDX-License-Identifier: AGPL-3.0-or-later` to every source file
across decnet/, decnet_web/, tests/, scripts/, and tools/.

Rationale: closes the GPLv3 ASP loophole so any party operating a
modified DECNET as a network service must offer their modified
source. Personal copyright (Samuel Paschuan) + inbound=outbound
contributions make a future unilateral relicense infeasible.

- LICENSE: full AGPL-3.0 text (gnu.org/licenses/agpl-3.0.txt)
- COPYRIGHT: project copyright notice
- tools/add_spdx_headers.py: idempotent header injector
  (shebang- and PEP 263-aware)

Touches 1565 source files (.py, .ts, .tsx, .js, .jsx, .css, .sh).
No behavior change; comments only.
2026-05-22 21:04:16 -04:00

287 lines
11 KiB
Python

# SPDX-License-Identifier: AGPL-3.0-or-later
"""SQLite + sqlite-vec backend.
Lazy-imports the ``sqlite_vec`` extension. If the extension isn't
available (the package isn't installed, or the host's libsqlite3 is too
old to load loadable extensions), construction raises
:class:`SqliteVecUnavailable`; the factory catches that and falls back
to :class:`~decnet.vectorstore.fake.FakeVectorStore` with a warning.
Schema:
CREATE TABLE vectors (
kind TEXT NOT NULL,
id TEXT NOT NULL,
extractor_version INTEGER NOT NULL DEFAULT 1,
dim INTEGER NOT NULL,
PRIMARY KEY (kind, id)
);
CREATE VIRTUAL TABLE vec_<kind> USING vec0(
embedding float[<dim>]
);
A vec0 virtual table is created lazily per-kind on first insert
(distinct ``kind`` values get distinct vec0 tables because vec0's dim
is a schema-time constant). The ``vectors`` row is the source of truth
for metadata (extractor_version, dim) and for the (kind, id) → rowid
mapping; vec0 stores only the embedding, keyed by an INTEGER rowid.
"""
from __future__ import annotations
import asyncio
import logging
import sqlite3
import threading
from pathlib import Path
from typing import Optional, Sequence
from decnet.vectorstore.base import BaseVectorStore, Neighbor, VectorRecord
LOG = logging.getLogger(__name__)
class SqliteVecUnavailable(RuntimeError):
"""sqlite_vec couldn't be loaded (extension missing / too-old sqlite3)."""
def _load_sqlite_vec(conn: sqlite3.Connection) -> None:
try:
import sqlite_vec
except ImportError as e:
raise SqliteVecUnavailable("sqlite_vec package not installed") from e
try:
conn.enable_load_extension(True)
except (AttributeError, sqlite3.NotSupportedError) as e:
raise SqliteVecUnavailable(
"system sqlite3 was built without loadable-extension support"
) from e
try:
sqlite_vec.load(conn)
except sqlite3.OperationalError as e:
raise SqliteVecUnavailable(f"sqlite_vec load failed: {e}") from e
finally:
try:
conn.enable_load_extension(False)
except sqlite3.NotSupportedError:
pass
class SqliteVecVectorStore(BaseVectorStore):
"""sqlite-vec backed vector store. Single-file, async-friendly via
:func:`asyncio.to_thread`. Keep one instance per process.
"""
def __init__(self, db_path: str) -> None:
self._db_path = db_path
self._conn: Optional[sqlite3.Connection] = None
self._lock = threading.Lock()
# {kind: dim} cached after first insert/probe.
self._kinds: dict[str, int] = {}
async def initialize(self) -> None:
await asyncio.to_thread(self._init_sync)
def _init_sync(self) -> None:
Path(self._db_path).parent.mkdir(parents=True, exist_ok=True)
conn = sqlite3.connect(self._db_path, check_same_thread=False)
_load_sqlite_vec(conn) # raises SqliteVecUnavailable on failure
conn.execute("PRAGMA journal_mode=WAL")
conn.execute(
"""
CREATE TABLE IF NOT EXISTS vectors (
kind TEXT NOT NULL,
id TEXT NOT NULL,
extractor_version INTEGER NOT NULL DEFAULT 1,
dim INTEGER NOT NULL,
rowid_in_vec INTEGER NOT NULL,
PRIMARY KEY (kind, id)
)
"""
)
conn.execute(
"CREATE INDEX IF NOT EXISTS ix_vectors_kind ON vectors(kind)"
)
conn.commit()
# Re-hydrate kind→dim cache from any existing rows so a process
# restart doesn't accept a mismatched dim on the first insert.
for row in conn.execute("SELECT kind, dim FROM vectors GROUP BY kind"):
self._kinds[row[0]] = int(row[1])
self._conn = conn
async def close(self) -> None:
await asyncio.to_thread(self._close_sync)
def _close_sync(self) -> None:
with self._lock:
if self._conn is not None:
self._conn.close()
self._conn = None
async def health(self) -> dict:
return await asyncio.to_thread(self._health_sync)
def _health_sync(self) -> dict:
if self._conn is None:
return {"ok": False, "backend": "sqlite_vec", "reason": "not initialized"}
try:
row = self._conn.execute("SELECT COUNT(*) FROM vectors").fetchone()
return {
"ok": True,
"backend": "sqlite_vec",
"kinds": len(self._kinds),
"vectors": int(row[0]) if row else 0,
}
except sqlite3.Error as e:
return {"ok": False, "backend": "sqlite_vec", "reason": str(e)}
@staticmethod
def _vec_table(kind: str) -> str:
# Validate the kind so it can't break out of the table name.
# Allowed: ascii letters, digits, underscore. Anything else =
# programmer error; raise loudly.
if not kind or not all(c.isalnum() or c == "_" for c in kind):
raise ValueError(f"invalid kind {kind!r}: ascii [a-z0-9_] only")
return f"vec_{kind}"
def _ensure_kind_table(self, kind: str, dim: int) -> None:
assert self._conn is not None # nosec B101
existing = self._kinds.get(kind)
if existing is None:
# vec_<kind> identifier is validated by _vec_table() to be
# ascii [a-z0-9_] only, and dim is int-cast — no injection
# vector. The f-string is the only way to interpolate a
# virtual-table name; placeholders aren't allowed for DDL.
ddl = ( # nosec B608
f"CREATE VIRTUAL TABLE IF NOT EXISTS {self._vec_table(kind)} "
f"USING vec0(embedding float[{int(dim)}])"
)
self._conn.execute(ddl)
self._conn.commit()
self._kinds[kind] = dim
elif existing != dim:
raise ValueError(
f"vector dim mismatch for kind={kind!r}: "
f"expected {existing}, got {dim}"
)
async def insert(
self, kind: str, id: str, vector: Sequence[float],
*, extractor_version: int = 1,
) -> None:
await asyncio.to_thread(
self._insert_sync, kind, id, list(vector), int(extractor_version)
)
def _insert_sync(
self, kind: str, id: str, vector: list[float], extractor_version: int,
) -> None:
with self._lock:
assert self._conn is not None # nosec B101
dim = len(vector)
self._ensure_kind_table(kind, dim)
vec_table = self._vec_table(kind)
cur = self._conn.cursor()
existing = cur.execute(
"SELECT rowid_in_vec FROM vectors WHERE kind=? AND id=?",
(kind, id),
).fetchone()
if existing is not None:
rowid = int(existing[0])
# vec_table is validated; rowid is bound. Safe.
cur.execute(f"DELETE FROM {vec_table} WHERE rowid=?", (rowid,)) # nosec B608
import struct
blob = struct.pack(f"{dim}f", *vector)
cur.execute(f"INSERT INTO {vec_table}(embedding) VALUES (?)", (blob,)) # nosec B608
new_rowid = cur.lastrowid
cur.execute(
"INSERT OR REPLACE INTO vectors"
"(kind, id, extractor_version, dim, rowid_in_vec) "
"VALUES (?, ?, ?, ?, ?)",
(kind, id, extractor_version, dim, new_rowid),
)
self._conn.commit()
async def get(self, kind: str, id: str) -> Optional[VectorRecord]:
return await asyncio.to_thread(self._get_sync, kind, id)
def _get_sync(self, kind: str, id: str) -> Optional[VectorRecord]:
with self._lock:
assert self._conn is not None # nosec B101
row = self._conn.execute(
"SELECT extractor_version, dim, rowid_in_vec "
"FROM vectors WHERE kind=? AND id=?",
(kind, id),
).fetchone()
if row is None:
return None
ext_v, dim, rowid = int(row[0]), int(row[1]), int(row[2])
vec_table = self._vec_table(kind)
blob_row = self._conn.execute(f"SELECT embedding FROM {vec_table} WHERE rowid=?", (rowid,)).fetchone() # nosec B608
if blob_row is None:
return None
import struct
vec = list(struct.unpack(f"{dim}f", blob_row[0]))
return VectorRecord(
kind=kind, id=id, vector=vec, dim=dim,
extractor_version=ext_v,
)
async def delete(self, kind: str, id: str) -> bool:
return await asyncio.to_thread(self._delete_sync, kind, id)
def _delete_sync(self, kind: str, id: str) -> bool:
with self._lock:
assert self._conn is not None # nosec B101
row = self._conn.execute(
"SELECT rowid_in_vec FROM vectors WHERE kind=? AND id=?",
(kind, id),
).fetchone()
if row is None:
return False
rowid = int(row[0])
vec_table = self._vec_table(kind)
self._conn.execute(f"DELETE FROM {vec_table} WHERE rowid=?", (rowid,)) # nosec B608
self._conn.execute(
"DELETE FROM vectors WHERE kind=? AND id=?", (kind, id)
)
self._conn.commit()
return True
async def knn(
self, kind: str, vector: Sequence[float], k: int = 10,
) -> list[Neighbor]:
return await asyncio.to_thread(self._knn_sync, kind, list(vector), int(k))
def _knn_sync(self, kind: str, vector: list[float], k: int) -> list[Neighbor]:
with self._lock:
assert self._conn is not None # nosec B101
existing_dim = self._kinds.get(kind)
if existing_dim is None:
return []
if len(vector) != existing_dim:
raise ValueError(
f"query dim {len(vector)} != stored dim {existing_dim} "
f"for kind={kind!r}"
)
vec_table = self._vec_table(kind)
import struct
qblob = struct.pack(f"{existing_dim}f", *vector)
knn_sql = f"SELECT rowid, distance FROM {vec_table} WHERE embedding MATCH ? ORDER BY distance LIMIT ?" # nosec B608
rows = self._conn.execute(knn_sql, (qblob, max(0, k))).fetchall()
if not rows:
return []
id_map = {
int(r[0]): r[1]
for r in self._conn.execute(
"SELECT rowid_in_vec, id FROM vectors WHERE kind=?",
(kind,),
)
}
out: list[Neighbor] = []
for rowid, dist in rows:
rid = id_map.get(int(rowid))
if rid is None:
continue
out.append(Neighbor(kind=kind, id=rid, distance=float(dist)))
return out