File size: 7,782 Bytes
6b62834 | 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 | """Database layer — SQLite-backed persistence for sessions, documents, and metadata.
Replaces the in-memory dicts used during early development with a proper
persistent store. Uses aiosqlite for async access so it integrates cleanly
with the FastAPI / asyncio stack.
"""
from __future__ import annotations
import sqlite3
from pathlib import Path
from typing import Optional
# ═══════════════════════════════════════════════════════════════
# Connection management
# ═══════════════════════════════════════════════════════════════
class Database:
"""Thin wrapper around a SQLite connection with schema management."""
def __init__(self, db_path: str | Path = "data/agentic_rag.db"):
self._path = Path(db_path)
self._path.parent.mkdir(parents=True, exist_ok=True)
self._conn: Optional[sqlite3.Connection] = None
# ── Lifecycle ─────────────────────────────────
@property
def conn(self) -> sqlite3.Connection:
if self._conn is None:
self._conn = sqlite3.connect(str(self._path))
self._conn.row_factory = sqlite3.Row
self._conn.execute("PRAGMA journal_mode=WAL")
self._conn.execute("PRAGMA foreign_keys=ON")
return self._conn
def close(self) -> None:
if self._conn:
self._conn.close()
self._conn = None
# ── Schema ────────────────────────────────────
SCHEMA_VERSION = 1
def init_schema(self) -> None:
"""Create tables if they don't exist (idempotent)."""
c = self.conn
c.executescript("""
-- Schema versioning
CREATE TABLE IF NOT EXISTS _schema (
version INTEGER PRIMARY KEY,
applied_at TEXT NOT NULL DEFAULT (datetime('now'))
);
-- Sessions (chat conversation containers)
CREATE TABLE IF NOT EXISTS sessions (
id TEXT PRIMARY KEY,
user_id TEXT NOT NULL DEFAULT 'default',
title TEXT NOT NULL DEFAULT '',
metadata TEXT NOT NULL DEFAULT '{}',
created_at TEXT NOT NULL DEFAULT (datetime('now')),
updated_at TEXT NOT NULL DEFAULT (datetime('now'))
);
-- Messages within a session
CREATE TABLE IF NOT EXISTS messages (
id INTEGER PRIMARY KEY AUTOINCREMENT,
session_id TEXT NOT NULL REFERENCES sessions(id) ON DELETE CASCADE,
role TEXT NOT NULL, -- 'system' | 'user' | 'assistant' | 'tool'
content TEXT NOT NULL DEFAULT '',
tool_calls TEXT NOT NULL DEFAULT '[]',
tool_call_id TEXT DEFAULT NULL,
created_at TEXT NOT NULL DEFAULT (datetime('now'))
);
CREATE INDEX IF NOT EXISTS idx_messages_session
ON messages(session_id, id);
-- Documents ingested into the knowledge base
CREATE TABLE IF NOT EXISTS documents (
id TEXT PRIMARY KEY,
source TEXT NOT NULL DEFAULT '',
source_type TEXT NOT NULL DEFAULT 'text',
content_preview TEXT NOT NULL DEFAULT '',
item_count INTEGER NOT NULL DEFAULT 0,
metadata TEXT NOT NULL DEFAULT '{}',
created_at TEXT NOT NULL DEFAULT (datetime('now'))
);
-- Content items (individual chunks / images / tables)
CREATE TABLE IF NOT EXISTS content_items (
id TEXT PRIMARY KEY,
doc_id TEXT NOT NULL REFERENCES documents(id) ON DELETE CASCADE,
type TEXT NOT NULL DEFAULT 'text',
text TEXT NOT NULL DEFAULT '',
img_path TEXT NOT NULL DEFAULT '',
table_body TEXT NOT NULL DEFAULT '',
page_idx INTEGER NOT NULL DEFAULT 0,
metadata TEXT NOT NULL DEFAULT '{}',
created_at TEXT NOT NULL DEFAULT (datetime('now'))
);
CREATE INDEX IF NOT EXISTS idx_content_doc
ON content_items(doc_id);
CREATE INDEX IF NOT EXISTS idx_content_type
ON content_items(type);
-- Platform-to-session bindings (for messaging gateway)
CREATE TABLE IF NOT EXISTS platform_sessions (
platform TEXT NOT NULL,
platform_user_id TEXT NOT NULL,
chat_id TEXT NOT NULL DEFAULT '',
session_id TEXT NOT NULL REFERENCES sessions(id) ON DELETE CASCADE,
created_at TEXT NOT NULL DEFAULT (datetime('now')),
PRIMARY KEY (platform, platform_user_id, chat_id)
);
-- Key-value store for application config / cache
CREATE TABLE IF NOT EXISTS kv_store (
key TEXT PRIMARY KEY,
value TEXT NOT NULL DEFAULT '',
updated_at TEXT NOT NULL DEFAULT (datetime('now'))
);
""")
# Record schema version
existing = c.execute(
"SELECT version FROM _schema WHERE version = ?",
(self.SCHEMA_VERSION,),
).fetchone()
if not existing:
c.execute(
"INSERT INTO _schema (version) VALUES (?)",
(self.SCHEMA_VERSION,),
)
c.commit()
# ── Raw SQL helpers ───────────────────────────
def execute(self, sql: str, params: tuple = ()) -> sqlite3.Cursor:
return self.conn.execute(sql, params)
def executemany(self, sql: str, params_list: list[tuple]) -> sqlite3.Cursor:
return self.conn.executemany(sql, params_list)
def commit(self) -> None:
self.conn.commit()
def fetchone(self, sql: str, params: tuple = ()) -> Optional[sqlite3.Row]:
return self.conn.execute(sql, params).fetchone()
def fetchall(self, sql: str, params: tuple = ()) -> list[sqlite3.Row]:
return self.conn.execute(sql, params).fetchall()
# ═══════════════════════════════════════════════════════════════
# Global instance
# ═══════════════════════════════════════════════════════════════
_db: Optional[Database] = None
def get_db(db_path: str | Path = "") -> Database:
"""Get or create the global database instance."""
global _db
if _db is None:
path = db_path or "data/agentic_rag.db"
try:
from agentic_rag.config.settings import get_settings
path = get_settings().db_path
except Exception:
pass
_db = Database(path)
_db.init_schema()
return _db
def init_db(db_path: str | Path = "") -> Database:
"""Explicitly initialise the database (call at app startup)."""
global _db
_db = Database(db_path or "data/agentic_rag.db")
_db.init_schema()
return _db
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