Make the empty service default to SERVING state

src/python/grpcio_health_checking/grpc_health/v1/_async.py

@@ -30,7 +30,7 @@ class HealthServicer(_health_pb2_grpc.HealthServicer):
     _gracefully_shutting_down: bool
 
     def __init__(self) -> None:
-        self._server_status = dict()
+        self._server_status = {"": _health_pb2.HealthCheckResponse.SERVING}
         self._server_watchers = collections.defaultdict(asyncio.Condition)
         self._gracefully_shutting_down = False
 

src/python/grpcio_health_checking/grpc_health/v1/health.py

@@ -85,7 +85,7 @@ class HealthServicer(_health_pb2_grpc.HealthServicer):
                  experimental_non_blocking=True,
                  experimental_thread_pool=None):
         self._lock = threading.RLock()
-        self._server_status = {}
+        self._server_status = {"": _health_pb2.HealthCheckResponse.SERVING}
         self._send_response_callbacks = {}
         self.Watch.__func__.experimental_non_blocking = experimental_non_blocking
         self.Watch.__func__.experimental_thread_pool = experimental_thread_pool

src/python/grpcio_tests/tests/health_check/_health_servicer_test.py

@@ -50,7 +50,6 @@ class BaseWatchTests(object):
             self._servicer = health.HealthServicer(
                 experimental_non_blocking=non_blocking,
                 experimental_thread_pool=thread_pool)
-            self._servicer.set('', health_pb2.HealthCheckResponse.SERVING)
             self._servicer.set(_SERVING_SERVICE,
                                health_pb2.HealthCheckResponse.SERVING)
             self._servicer.set(_UNKNOWN_SERVICE,

src/python/grpcio_tests/tests_aio/health_check/health_servicer_test.py

@@ -47,8 +47,6 @@ class HealthServicerTest(AioTestBase):
 
     async def setUp(self):
         self._servicer = health.aio.HealthServicer()
-        await self._servicer.set(health.OVERALL_HEALTH,
-                                 health_pb2.HealthCheckResponse.SERVING)
         await self._servicer.set(_SERVING_SERVICE,
                                  health_pb2.HealthCheckResponse.SERVING)
         await self._servicer.set(_UNKNOWN_SERVICE,