Support token

Signed-off-by: Jael Gu <mengjia.gu@zilliz.com>

README.md

@@ -52,6 +52,13 @@ Create the operator via the following factory method:
 
 **Parameters:**
 
+All connection arguments are set as None by default. You must provide at least one valid value for uri or host/port.
+The order of use: uri > host/port, token > user/password.
+
+***uri:*** *str*
+
+The uri for Milvus.
+
 ***host:*** *str*
 
 The host for Milvus.
@@ -60,6 +67,10 @@ The host for Milvus.
 
 The port for Milvus.
 
+***token:*** *str*
+
+The token for Milvus.
+
 ***user:*** *str*
 
 The user for Zilliz Cloud, defaults to None.

milvus_client.py

@@ -1,5 +1,7 @@
 import uuid
 import logging
+from typing import Union
+
 from towhee.operator import PyOperator, SharedType
 from pymilvus import connections, Collection
 
@@ -12,15 +14,29 @@ class MilvusClient(PyOperator):
     Milvus ANN index class.
     """
 
-    def __init__(self, host: str, port: int, user: str = None, password: str = None):
-        self._host = host
-        self._port = port
+    def __init__(self,
+                 uri: str = None,
+                 host: str = None,
+                 port: Union[int, str] = None,
+                 token: str = None,
+                 user: str = None,
+                 password: str = None
+                 ):
         self._connect_name = uuid.uuid4().hex
-        if None in [user, password]:
-            connections.connect(alias=self._connect_name, host=self._host, port=self._port)
+        self._connection_args = {'alias': self._connect_name}
+        
+        if uri is not None:
+            self._connection_args['uri'] = uri
+        elif all(x is not None for x in [host, port]):
+            self._connection_args['host'] = host
+            self._connection_args['port'] = port
         else:
-            connections.connect(alias=self._connect_name, host=self._host, port=self._port,
-                                user=user, password=password, secure=True)
+            raise ConnectionError('Received invalid connection arguments.')
+
+        if any(x is None for x in [token, user, password]):
+            self._connection_args['secure'] = True
+
+        connections.connect(**self._connection_args)
 
     def __call__(self, collection_name: str, *data):
         """