feat:1.数据库存储功能添加（初版）2.后端REST API版本代码清理

backend/db/database.py

@@ -0,0 +1,95 @@
+"""
+数据库连接管理模块
+使用 SQLAlchemy ORM，支持同步操作
+"""
+
+import os
+import yaml
+from typing import Generator
+from contextlib import contextmanager
+import json
+
+from sqlalchemy import create_engine, text
+from sqlalchemy.orm import sessionmaker, declarative_base
+from sqlalchemy.pool import QueuePool
+from sqlalchemy.dialects.postgresql import dialect as pg_dialect
+
+# 读取配置
+yaml_file = os.path.join(os.getcwd(), "config", "config.yaml")
+try:
+    with open(yaml_file, "r", encoding="utf-8") as file:
+        config = yaml.safe_load(file).get("database", {})
+except Exception:
+    config = {}
+
+
+def get_database_url() -> str:
+    """获取数据库连接 URL"""
+    # 优先使用环境变量
+    host = os.getenv("DB_HOST", config.get("host", "localhost"))
+    port = os.getenv("DB_PORT", config.get("port", "5432"))
+    user = os.getenv("DB_USER", config.get("username", "postgres"))
+    password = os.getenv("DB_PASSWORD", config.get("password", ""))
+    dbname = os.getenv("DB_NAME", config.get("name", "agentcoord"))
+
+    return f"postgresql://{user}:{password}@{host}:{port}/{dbname}"
+
+
+# 创建引擎
+DATABASE_URL = get_database_url()
+engine = create_engine(
+    DATABASE_URL,
+    poolclass=QueuePool,
+    pool_size=config.get("pool_size", 10),
+    max_overflow=config.get("max_overflow", 20),
+    pool_pre_ping=True,
+    echo=False,
+    # JSONB 类型处理器配置
+    json_serializer=lambda obj: json.dumps(obj, ensure_ascii=False),
+    json_deserializer=lambda s: json.loads(s) if isinstance(s, str) else s
+)
+
+# 创建会话工厂
+SessionLocal = sessionmaker(autocommit=False, autoflush=False, bind=engine)
+
+# 基础类
+Base = declarative_base()
+
+
+def get_db() -> Generator:
+    """
+    获取数据库会话
+    用法: for db in get_db(): ...
+    """
+    db = SessionLocal()
+    try:
+        yield db
+    finally:
+        db.close()
+
+
+@contextmanager
+def get_db_context() -> Generator:
+    """
+    上下文管理器方式获取数据库会话
+    用法: with get_db_context() as db: ...
+    """
+    db = SessionLocal()
+    try:
+        yield db
+        db.commit()
+    except Exception as e:
+        db.rollback()
+        raise
+    finally:
+        db.close()
+
+
+def test_connection() -> bool:
+    """测试数据库连接"""
+    try:
+        with engine.connect() as conn:
+            conn.execute(text("SELECT 1"))
+        return True
+    except Exception as e:
+        return False