调整代码，支持项目切换，打开不同数据库的连接

app/infra/db/postgresql/router.py

@@ -1,6 +1,7 @@
-from fastapi import APIRouter, Depends, HTTPException, Query
+from fastapi import APIRouter, Depends, HTTPException, Query, Body
 from typing import Optional
 from psycopg import AsyncConnection
+from pydantic import BaseModel
 
 from .database import get_database_instance
 from .scada_info import ScadaRepository
@@ -9,6 +10,10 @@ from .scheme import SchemeRepository
 router = APIRouter()
 
 
+class DatabaseConfig(BaseModel):
+    db_name: str
+
+
 # 创建支持数据库选择的连接依赖函数
 async def get_database_connection(
     db_name: Optional[str] = Query(
@@ -21,6 +26,26 @@ async def get_database_connection(
         yield conn
 
 
+@router.post("/postgres/open-database")
+async def open_database(config: DatabaseConfig):
+    """
+    尝试连接指定数据库，如果成功则返回成功消息
+    """
+    try:
+        instance = await get_database_instance(config.db_name)
+        # 尝试获取连接并执行简单查询以验证连接
+        async with instance.get_connection() as conn:
+            async with conn.cursor() as cur:
+                await cur.execute("SELECT 1")
+                await cur.fetchone()
+        
+        return {"success": True, "message": f"Successfully connected to database: {config.db_name}"}
+    except Exception as e:
+        raise HTTPException(
+            status_code=500, detail=f"Failed to connect to database {config.db_name}: {str(e)}"
+        )
+
+
 @router.get("/scada-info")
 async def get_scada_info_with_connection(
     conn: AsyncConnection = Depends(get_database_connection),