(do not merge) fix: implement proper async signal handling for graceful server shutdown

connector_builder_mcp/server.py

@@ -5,8 +5,10 @@
 """
 
 import asyncio
+import signal
 import sys
 
+import anyio
 from fastmcp import FastMCP
 
 from connector_builder_mcp._util import initialize_logging
@@ -22,13 +24,35 @@
 def main() -> None:
     """Main entry point for the Builder MCP server."""
     print("Starting Builder MCP server.", file=sys.stderr)
+
+    async def run_server():
+        """Run the server with proper signal handling."""
+        shutdown_event = asyncio.Event()
+
+        def signal_handler():
+            print("Builder MCP server interrupted by user.", file=sys.stderr)
+            shutdown_event.set()
+
+        if sys.platform != "win32":
+            loop = asyncio.get_running_loop()
+            for sig in (signal.SIGTERM, signal.SIGINT):
+                loop.add_signal_handler(sig, signal_handler)
+
+        try:
+            async with anyio.create_task_group() as tg:
+                tg.start_soon(app.run_stdio_async)
+                await shutdown_event.wait()
+                tg.cancel_scope.cancel()
+        except anyio.get_cancelled_exc_class():
+            pass
+        except Exception as ex:
+            print(f"Error running Builder MCP server: {ex}", file=sys.stderr)
+            sys.exit(1)
+
     try:
-        asyncio.run(app.run_stdio_async())
+        asyncio.run(run_server())
     except KeyboardInterrupt:
         print("Builder MCP server interrupted by user.", file=sys.stderr)
-    except Exception as ex:
-        print(f"Error running Builder MCP server: {ex}", file=sys.stderr)
-        sys.exit(1)
 
     print("Builder MCP server stopped.", file=sys.stderr)
     sys.exit(0)

pyproject.toml

@@ -9,6 +9,7 @@ readme = "README.md"
 requires-python = ">=3.11"
 dependencies = [
     "airbyte-cdk>=6.61.6,<7.0",
+    "anyio>=4.0.0,<5.0",
     "fastmcp>=2.12.1,<3.0",
     "jsonschema>=4.0.0,<5.0",
     "privatebin>=0.3.0,<1.0",