diff --git a/mishards/__init__.py b/mishards/__init__.py
index c1cea84861..76f3168b51 100644
--- a/mishards/__init__.py
+++ b/mishards/__init__.py
@@ -2,22 +2,29 @@ from mishards import settings
 
 from mishards.db_base import DB
 db = DB()
-db.init_db(uri=settings.SQLALCHEMY_DATABASE_URI, echo=settings.SQL_ECHO)
-
-from mishards.connections import ConnectionMgr
-connect_mgr = ConnectionMgr()
-
-from sd import ProviderManager
-
-sd_proiver_class = ProviderManager.get_provider(settings.SD_PROVIDER)
-discover = sd_proiver_class(settings=settings.SD_PROVIDER_SETTINGS, conn_mgr=connect_mgr)
-
-from tracing.factory import TracerFactory
-from grpc_utils import GrpcSpanDecorator
-tracer = TracerFactory.new_tracer(settings.TRACING_TYPE, settings.TracingConfig,
-        span_decorator=GrpcSpanDecorator())
 
 from mishards.server import Server
-grpc_server = Server(conn_mgr=connect_mgr, tracer=tracer)
+grpc_server = Server()
 
-from mishards import exception_handlers
+def create_app(testing_config=None):
+    config = testing_config if testing_config else settings.DefaultConfig
+    db.init_db(uri=config.SQLALCHEMY_DATABASE_URI, echo=config.SQL_ECHO)
+
+    from mishards.connections import ConnectionMgr
+    connect_mgr = ConnectionMgr()
+
+    from sd import ProviderManager
+
+    sd_proiver_class = ProviderManager.get_provider(settings.SD_PROVIDER)
+    discover = sd_proiver_class(settings=settings.SD_PROVIDER_SETTINGS, conn_mgr=connect_mgr)
+
+    from tracing.factory import TracerFactory
+    from grpc_utils import GrpcSpanDecorator
+    tracer = TracerFactory.new_tracer(settings.TRACING_TYPE, settings.TracingConfig,
+        span_decorator=GrpcSpanDecorator())
+
+    grpc_server.init_app(conn_mgr=connect_mgr, tracer=tracer, discover=discover)
+
+    from mishards import exception_handlers
+
+    return grpc_server
diff --git a/mishards/main.py b/mishards/main.py
index 7fac55dfa2..9197fbf598 100644
--- a/mishards/main.py
+++ b/mishards/main.py
@@ -2,10 +2,10 @@ import os, sys
 sys.path.append(os.path.dirname(os.path.dirname(os.path.abspath(__file__))))
 
 from mishards import (
-        settings,
-        grpc_server as server)
+        settings, create_app)
 
 def main():
+    server = create_app()
     server.run(port=settings.SERVER_PORT)
     return 0
 
diff --git a/mishards/server.py b/mishards/server.py
index 1f72a8812d..0ca4a8f866 100644
--- a/mishards/server.py
+++ b/mishards/server.py
@@ -12,20 +12,23 @@ from jaeger_client import Config
 from milvus.grpc_gen.milvus_pb2_grpc import add_MilvusServiceServicer_to_server
 from mishards.grpc_utils import is_grpc_method
 from mishards.service_handler import ServiceHandler
-from mishards import settings, discover
+from mishards import settings
 
 logger = logging.getLogger(__name__)
 
 
 class Server:
-    def __init__(self, conn_mgr, tracer, port=19530, max_workers=10, **kwargs):
+    def __init__(self):
         self.pre_run_handlers = set()
         self.grpc_methods = set()
         self.error_handlers = {}
         self.exit_flag = False
+
+    def init_app(self, conn_mgr, tracer, discover, port=19530, max_workers=10, **kwargs):
         self.port = int(port)
         self.conn_mgr = conn_mgr
         self.tracer = tracer
+        self.discover = discover
 
         self.server_impl = grpc.server(
             thread_pool=futures.ThreadPoolExecutor(max_workers=max_workers),
@@ -73,7 +76,7 @@ class Server:
     def on_pre_run(self):
         for handler in self.pre_run_handlers:
             handler()
-        discover.start()
+        self.discover.start()
 
     def start(self, port=None):
         handler_class = self.decorate_handler(ServiceHandler)
diff --git a/mishards/settings.py b/mishards/settings.py
index 4a70d44561..b42cb791f6 100644
--- a/mishards/settings.py
+++ b/mishards/settings.py
@@ -16,9 +16,6 @@ TIMEZONE = env.str('TIMEZONE', 'UTC')
 from utils.logger_helper import config
 config(LOG_LEVEL, LOG_PATH, LOG_NAME, TIMEZONE)
 
-SQLALCHEMY_DATABASE_URI = env.str('SQLALCHEMY_DATABASE_URI')
-SQL_ECHO = env.bool('SQL_ECHO', False)
-
 TIMEOUT = env.int('TIMEOUT', 60)
 MAX_RETRY = env.int('MAX_RETRY', 3)
 SEARCH_WORKER_SIZE = env.int('SEARCH_WORKER_SIZE', 10)
@@ -63,6 +60,15 @@ class TracingConfig:
         'logging': env.bool('TRACING_LOGGING', True)
     }
 
+class DefaultConfig:
+    SQLALCHEMY_DATABASE_URI = env.str('SQLALCHEMY_DATABASE_URI')
+    SQL_ECHO = env.bool('SQL_ECHO', False)
+
+# class TestingConfig(DefaultConfig):
+#     SQLALCHEMY_DATABASE_URI = env.str('SQLALCHEMY_DATABASE_TEST_URI')
+#     SQL_ECHO = env.bool('SQL_TEST_ECHO', False)
+
+
 if __name__ == '__main__':
     import logging
     logger = logging.getLogger(__name__)