haiku.rag/haiku_rag_slim/haiku/rag/client/session.py
Yiorgis Gozadinos 187946a7ae
Name the remedy for a missing configured database and list the databases an unknown name could have meant
A configured or default database that does not exist raises
SourceUnavailableError with the way to create it and without its location.
An unknown --db-name lists the databases there are, configured or default.
The CHANGELOG records Store.db_path, SingleDatabaseSession(ref, config),
the empty lancedb.uri migration and the error-type change.
2026-09-03 15:26:42 +03:00

322 lines
12 KiB
Python

import asyncio
import logging
from pathlib import Path
from time import monotonic
from typing import TYPE_CHECKING, Any
from haiku.rag.client.scope import DatabaseRef, DatabaseScope
from haiku.rag.config import AppConfig
from haiku.rag.store.engine import Store
from haiku.rag.store.exceptions import (
ConfigMismatchError,
MigrationRequiredError,
ReadOnlyError,
SourceUnavailableError,
UnknownDatabaseError,
)
from haiku.rag.store.repositories.chunk import ChunkRepository
from haiku.rag.store.repositories.document import DocumentRepository
from haiku.rag.store.repositories.document_item import DocumentItemRepository
if TYPE_CHECKING:
from haiku.rag.store.models.document import Document
logger = logging.getLogger(__name__)
# Throttle for the background auto-vacuum: under sustained ingestion, scheduling
# a compaction on every write degenerates into back-to-back optimize() passes
# that churn the blob-bearing documents table. Fire at most one per interval; a
# final vacuum on close collapses anything throttled here.
_VACUUM_MIN_INTERVAL_S = 300.0
# Failures whose message names the remedy and never the location. `open()`
# prefixes the failing database's name.
_NAMEABLE_FAILURES = (MigrationRequiredError, ConfigMismatchError, ReadOnlyError)
async def aclose_quietly(closeable: Any, what: str) -> None:
"""Close; a failure is logged, never raised."""
try:
await closeable.aclose()
except Exception:
logger.debug("Closing the %s failed on teardown", what, exc_info=True)
class SingleDatabaseSession:
"""One database: its store, its repositories, and their lifecycle.
Everything that needs a store lives here, so nothing above has to ask whether
it has one. Built from the resolved reference: ``source`` is the name it
answers to, and the store receives its location.
``ref``, ``config``, ``read_only`` and ``source`` are readable: a client
borrowing this session reports them as its own.
"""
def __init__(
self,
ref: DatabaseRef,
config: AppConfig,
*,
skip_validation: bool = False,
create: bool = False,
read_only: bool = False,
) -> None:
self.ref = ref
self.config = config
self.read_only = read_only
self._skip_validation = skip_validation
self._create = create
self._vacuum_tasks: set[asyncio.Task] = set()
self._last_vacuum_at: float | None = None
self._vacuum_dirty = False
@property
def source(self) -> str:
return self.ref.name
@property
def location(self) -> Path | str:
"""Where this database is: its path, or its URI."""
return self.ref.location
@property
def db_path(self) -> Path | None:
"""The local path, or None for a database behind a URI."""
return self.ref.db_path
async def open(self) -> "SingleDatabaseSession":
"""Connect, validate, and build the repositories."""
failure: str | None = None
try:
self.store = Store(
self.location,
config=self.config,
skip_validation=self._skip_validation,
create=self._create,
read_only=self.read_only,
)
# Close a partially initialized store: the caller's `async with`
# never entered, so its exit will not run.
try:
await self.store._initialize()
except BaseException:
self.store.close()
raise
except _NAMEABLE_FAILURES as error:
# The message keeps its remedy and gains the database's name.
if self.ref.given:
raise
raise type(error)(f"database {self.source!r}: {error}") from error
except Exception as error:
# A path the caller gave may be named: the caller knows it already.
if self.ref.given:
raise
failure = (
"does not exist; create it with `haiku-rag init` or `create=True`"
if isinstance(error, FileNotFoundError)
else f"could not be opened: {type(error).__name__}"
)
if failure is not None:
# Raised outside the handler: the exception carries neither a cause
# nor a location-bearing context.
raise SourceUnavailableError(f"database {self.source!r} {failure}")
self.document_repository = DocumentRepository(self.store)
self.chunk_repository = ChunkRepository(self.store)
self.document_item_repository = DocumentItemRepository(self.store)
return self
async def drain_vacuum(self) -> None:
"""Drain background vacuum work and run a final collapse before teardown.
The final pass runs whenever writes happened, not when tasks remain: a
debounced run may have scheduled none and still left versions behind. It
never runs without writes, so opening and closing a store writes nothing.
"""
if self._vacuum_tasks:
await asyncio.gather(*self._vacuum_tasks, return_exceptions=True)
if not self._vacuum_dirty:
return
self._vacuum_dirty = False
# Teardown runs during exception unwinding; a raising vacuum here would
# mask the original exception, so the drain stays best-effort.
try:
await self.store.vacuum()
except Exception:
logger.debug("Final vacuum on close failed", exc_info=True)
def schedule_vacuum(self) -> None:
"""Schedule a background vacuum, throttled to at most one per
``_VACUUM_MIN_INTERVAL_S``. The throttle only skips the background task —
``_vacuum_dirty`` still marks that a final vacuum on close is owed."""
self._vacuum_dirty = True
now = monotonic()
if (
self._last_vacuum_at is not None
and now - self._last_vacuum_at < _VACUUM_MIN_INTERVAL_S
):
return
self._last_vacuum_at = now
task = asyncio.create_task(self.store.vacuum())
self._vacuum_tasks.add(task)
task.add_done_callback(self._vacuum_tasks.discard)
def name(self, document: "Document | None") -> "Document | None":
"""`document`, told which database it came from."""
if document is not None:
document.source = self.source
return document
def name_all(self, documents: "list[Document]") -> "list[Document]":
"""`documents`, each told which database it came from."""
for document in documents:
document.source = self.source
return documents
async def get_document_by_id(self, document_id: str) -> "Document | None":
return self.name(await self.document_repository.get_by_id(document_id))
async def get_document_by_uri(self, uri: str) -> "Document | None":
return self.name(await self.document_repository.get_by_uri(uri))
async def list_documents(
self,
limit: int | None = None,
offset: int | None = None,
filter: str | None = None,
include_content: bool = False,
) -> "list[Document]":
return self.name_all(
await self.document_repository.list_all(
limit=limit,
offset=offset,
filter=filter,
include_content=include_content,
)
)
async def delete_document(self, document_id: str) -> bool:
"""Delete a document, cascading to children linked via
``metadata.parent_uri``.
The whole subtree (root + transitive children) is deleted under a single
write lock and a single version snapshot, so the cascade is atomic: any
failure restores every table to the pre-delete state, and no other write
can interleave between deleting a child and its parent.
"""
from haiku.rag.client.documents import parent_uri_filter
async with self.store.write_transaction():
# Resolve existence and collect the subtree under the lock so two
# concurrent deletes of the same id can't both proceed, and children
# can't appear or move between collection and deletion. parent_uri
# links a child to its parent's uri; walk transitively, guarding
# against cycles.
ids_to_delete: list[str] = []
seen: set[str] = set()
queue = [await self.get_document_by_id(document_id)]
while queue:
doc = queue.pop()
if doc is None or doc.id is None or doc.id in seen:
continue
seen.add(doc.id)
ids_to_delete.append(doc.id)
if doc.uri:
queue.extend(
await self.list_documents(filter=parent_uri_filter(doc.uri))
)
if not ids_to_delete:
return False
for doc_id in ids_to_delete:
await self.document_repository.delete(doc_id)
if self.config.storage.auto_vacuum:
self.schedule_vacuum()
return True
async def aclose(self) -> None:
"""Drain, release the embedder, and close the connection.
The store owns the embedder, so this is where it is released.
"""
await self.drain_vacuum()
await aclose_quietly(self.store.embedder, "embedder")
self.close()
def close(self) -> None:
"""Close the underlying store connection."""
self.store.close()
class FederatedSession:
"""Several databases, read as one. Reads only.
Composes single-database sessions and owns their teardown. They open on first
use: which databases a query covers is a per-query choice, and a database the
query does not cover stays closed.
"""
def __init__(
self,
scope: DatabaseScope,
config: AppConfig,
*,
skip_validation: bool = False,
read_only: bool = False,
) -> None:
self._refs: dict[str, DatabaseRef] = {ref.name: ref for ref in scope.databases}
self._config = config
self._skip_validation = skip_validation
self._read_only = read_only
self._sessions: dict[str, SingleDatabaseSession] = {}
self._lock = asyncio.Lock()
@property
def names(self) -> tuple[str, ...]:
"""The databases covered, in configured order."""
return tuple(self._refs)
async def sessions_for(self, names: list[str]) -> list[SingleDatabaseSession]:
"""The sessions for these databases, opening any not yet open.
Missing ones open together: on object storage a serial loop makes the
first query cost the sum of the opens.
"""
unknown = [name for name in names if name not in self._refs]
if unknown:
raise UnknownDatabaseError(
f"unknown database(s) {', '.join(sorted(unknown))}; configured: "
f"{', '.join(sorted(self._refs))}"
)
async with self._lock:
missing = [name for name in names if name not in self._sessions]
if missing:
opened = await asyncio.gather(
*(self._open(name) for name in missing),
return_exceptions=True,
)
for result in opened:
if isinstance(result, BaseException):
raise result
return [self._sessions[name] for name in names]
async def _open(self, name: str) -> None:
"""Open and register one database before returning to the fan-out.
Registered here because a cancelled `gather` discards its results.
"""
self._sessions[name] = await SingleDatabaseSession(
self._refs[name],
self._config,
skip_validation=self._skip_validation,
read_only=self._read_only,
).open()
async def aclose(self) -> None:
"""Close every database this session opened."""
for session in self._sessions.values():
await aclose_quietly(session, "database")
self._sessions.clear()