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brain-of-reese/app/models.py
T

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"""SQLAlchemy models (PostgreSQL 17 + pgvector).
Data model — see ``.agent/PLAN.md`` §Data Model:
* ``documents`` — one row per imported A9 file (full content, path, sha256 hash).
* ``chunks`` — retrieval units; each chunk points at its parent document
via ``document_id``. This is how an embedding maps back to
a document path (the "feed the whole document" requirement).
* ``query_log`` — observability: every question, its retrieval score, the
deflection decision, and latency.
"""
from __future__ import annotations
import uuid
from datetime import datetime
from pgvector.sqlalchemy import Vector
from sqlalchemy import (
Boolean,
DateTime,
Float,
ForeignKey,
Integer,
String,
Text,
UniqueConstraint,
func,
)
from sqlalchemy.dialects.postgresql import UUID
from sqlalchemy.orm import Mapped, mapped_column, relationship
from app.config import get_settings
from app.db import Base
# Single source of truth for the vector column size (see .agent/PLAN.md A6).
EMBEDDING_DIM: int = get_settings().embedding_dim
class Document(Base):
__tablename__ = "documents"
__table_args__ = (UniqueConstraint("source", "path", name="uq_documents_source_path"),)
id: Mapped[uuid.UUID] = mapped_column(UUID(as_uuid=True), primary_key=True, default=uuid.uuid4)
source: Mapped[str] = mapped_column(String(120), index=True) # e.g. "Homelab"
path: Mapped[str] = mapped_column(String(1000), index=True) # relative to source dir
full_path: Mapped[str] = mapped_column(String(2000)) # absolute path at import time
title: Mapped[str] = mapped_column(String(500))
content: Mapped[str] = mapped_column(Text) # full markdown — the RAG context
content_hash: Mapped[str] = mapped_column(String(64), index=True) # sha256 for change detection
indexed_at: Mapped[datetime] = mapped_column(DateTime(timezone=True), server_default=func.now())
chunks: Mapped[list[Chunk]] = relationship(
back_populates="document", cascade="all, delete-orphan"
)
class Chunk(Base):
__tablename__ = "chunks"
id: Mapped[uuid.UUID] = mapped_column(UUID(as_uuid=True), primary_key=True, default=uuid.uuid4)
document_id: Mapped[uuid.UUID] = mapped_column(
UUID(as_uuid=True), ForeignKey("documents.id", ondelete="CASCADE"), index=True
)
position: Mapped[int] = mapped_column(Integer)
content: Mapped[str] = mapped_column(Text)
embedding: Mapped[list[float] | None] = mapped_column(Vector(EMBEDDING_DIM))
document: Mapped[Document] = relationship(back_populates="chunks")
class QueryLog(Base):
__tablename__ = "query_log"
id: Mapped[uuid.UUID] = mapped_column(UUID(as_uuid=True), primary_key=True, default=uuid.uuid4)
question: Mapped[str] = mapped_column(Text)
top_score: Mapped[float] = mapped_column(Float, default=0.0) # best cosine similarity
#: Lexical (FTS) candidates matched — the OR-tsquery hit count (A8). NULL
#: for pre-hybrid rows (migration 0002).
fts_hits: Mapped[int | None] = mapped_column(Integer)
chunk_hits: Mapped[int] = mapped_column(Integer, default=0)
deflected: Mapped[bool] = mapped_column(Boolean, default=False) # True = honest "no idea"
sources: Mapped[str] = mapped_column(Text, default="") # comma-joined source paths
latency_ms: Mapped[int] = mapped_column(Integer, default=0)
created_at: Mapped[datetime] = mapped_column(DateTime(timezone=True), server_default=func.now())