refactor: connect client once at server startup via lifespan

src/tryton_mcp/config.py

@@ -1,5 +1,7 @@
 import os
+from contextlib import asynccontextmanager
 from dataclasses import dataclass, field
+from typing import Optional
 
 from sabatron_tryton_rpc_client.client import Client
 
@@ -19,6 +21,7 @@ class TrytonSettings:
     port: int = field(
         default_factory=lambda: int(os.environ.get("TRYTON_PORT", "8000"))
     )
+    _client: Optional[Client] = field(default=None, init=False, repr=False)
 
     def to_dict(self) -> dict:
         return {
@@ -30,7 +33,28 @@ class TrytonSettings:
         }
 
     def get_client(self) -> Client:
-        return Client(**self.to_dict())
+        if self._client is None:
+            self._client = Client(**self.to_dict())
+        return self._client
+
+    def connect(self):
+        client = self.get_client()
+        client.connect()
+
+    def disconnect(self):
+        if self._client is not None:
+            close_method = getattr(self._client, "close", None) or getattr(
+                self._client, "disconnect", None
+            )
+            if close_method:
+                close_method()
+            self._client = None
+
+    @asynccontextmanager
+    async def lifespan(self):
+        self.connect()
+        yield
+        self.disconnect()
 
     def __post_init__(self):
         if not self.hostname:

src/tryton_mcp/server.py

@@ -2,15 +2,22 @@
 MCP Server for Naliia Module
 """
 
-from sabatron_tryton_rpc_client.client import Client
+from contextlib import asynccontextmanager
 from fastmcp import FastMCP
-from typing import List
+from typing import List, AsyncIterator
 import datetime
 
 from tryton_mcp.config import settings
 
 
-mcp = FastMCP("Tryton MCP Server")
+@asynccontextmanager
+async def server_lifespan(server: FastMCP) -> AsyncIterator[None]:
+    settings.connect()
+    yield
+    settings.disconnect()
+
+
+mcp = FastMCP("Tryton MCP Server", lifespan=server_lifespan)
 
 
 @mcp.tool()
@@ -28,9 +35,7 @@ def create_schedule(
         }
     ]
 
-    client = Client(**settings.to_dict())
-
-    client.connect()
+    client = settings.get_client()
     name = "model.naliia.schedule.create"
     args = [example_schedule, {}]
     response = client.call(name, args)
@@ -40,9 +45,7 @@ def create_schedule(
 
 @mcp.tool()
 def find_service_centers():
-    client = Client(**settings.to_dict())
-
-    client.connect()
+    client = settings.get_client()
 
     name = "model.naliia.service_center.search_read"
     args = [[[]], 0, None, None, ["name", "address.street"], {}]
@@ -53,9 +56,7 @@ def find_service_centers():
 
 @mcp.tool()
 def find_products_and_services():
-    client = Client(**settings.to_dict())
-
-    client.connect()
+    client = settings.get_client()
 
     name = "model.product.product.search_read"
     args = [