Fixed grpc insecure channel connect

Author: miott

src/cisco_gnmi/builder.py

@@ -271,9 +271,11 @@ def construct(self):
         channel_ssl_creds = None
         channel_metadata_creds = None
         channel_creds = None
-        channel_ssl_creds = grpc.ssl_channel_credentials(
-            self.__root_certificates, self.__private_key, self.__certificate_chain
-        )
+        channel_ssl_creds = None
+        if any((self.__root_certificates, self.__private_key, self.__certificate_chain)):
+            channel_ssl_creds = grpc.ssl_channel_credentials(
+                self.__root_certificates, self.__private_key, self.__certificate_chain
+            )
         if self.__username and self.__password:
             channel_metadata_creds = grpc.metadata_call_credentials(
                 CiscoAuthPlugin(self.__username, self.__password)
@@ -284,25 +286,28 @@ def construct(self):
                 channel_ssl_creds, channel_metadata_creds
             )
             logging.debug("Using SSL/metadata authentication composite credentials.")
-        else:
+        elif channel_ssl_creds:
             channel_creds = channel_ssl_creds
             logging.debug("Using SSL credentials, no metadata authentication.")
-        if self.__ssl_target_name_override is not False:
-            if self.__ssl_target_name_override is None:
-                if not self.__root_certificates:
-                    raise Exception("Deriving override requires root certificate!")
-                self.__ssl_target_name_override = get_cn_from_cert(
-                    self.__root_certificates
+        if channel_creds:
+            if self.__ssl_target_name_override is not False:
+                if self.__ssl_target_name_override is None:
+                    if not self.__root_certificates:
+                        raise Exception("Deriving override requires root certificate!")
+                    self.__ssl_target_name_override = get_cn_from_cert(
+                        self.__root_certificates
+                    )
+                    logging.warning(
+                        "Overriding SSL option from certificate could increase MITM susceptibility!"
+                    )
+                self.set_channel_option(
+                    "grpc.ssl_target_name_override", self.__ssl_target_name_override
                 )
-                logging.warning(
-                    "Overriding SSL option from certificate could increase MITM susceptibility!"
-                )
-            self.set_channel_option(
-                "grpc.ssl_target_name_override", self.__ssl_target_name_override
+            channel = grpc.secure_channel(
+                self.__target_netloc.netloc, channel_creds, self.__channel_options
             )
-        channel = grpc.secure_channel(
-            self.__target_netloc.netloc, channel_creds, self.__channel_options
-        )
+        else:
+            channel = grpc.insecure_channel(self.__target_netloc.netloc)
         if self.__client_class is None:
             self.set_os()
         client = self.__client_class(channel)