CORD-1638 Rename ExampleTenant and drop obsolete references

Change-Id: Ia68efa15d84e536fd2f77aa3fea7ebabfd4a18c2
diff --git a/xos/tosca/resources/exampleserviceinstance.py b/xos/tosca/resources/exampleserviceinstance.py
new file mode 100644
index 0000000..7b8f640
--- /dev/null
+++ b/xos/tosca/resources/exampleserviceinstance.py
@@ -0,0 +1,44 @@
+# Copyright 2017-present Open Networking Foundation
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+# http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+from xosresource import XOSResource
+from core.models import Service
+from services.exampleservice.models import ExampleServiceInstance
+
+class XOSExampleServiceInstance(XOSResource):
+    provides = ["tosca.nodes.ExampleServiceInstance",
+                "tosca.nodes.ExampleTenant"            # deprecated
+                ]
+    xos_model = ExampleServiceInstance
+    name_field = "service_specific_id"
+    copyin_props = ("tenant_message",)
+
+    def get_xos_args(self, throw_exception=True):
+        args = super(XOSExampleServiceInstance, self).get_xos_args()
+
+        # ExampleServiceInstance must always have a provider_service
+        provider_name = self.get_requirement("tosca.relationships.TenantOfService", throw_exception=True)
+        if provider_name:
+            args["owner"] = self.get_xos_object(Service, throw_exception=True, name=provider_name)
+
+        return args
+
+    def get_existing_objs(self):
+        args = self.get_xos_args(throw_exception=False)
+        return ExampleServiceInstance.objects.filter(owner=args["owner"], service_specific_id=args["service_specific_id"])
+        return []
+
+    def can_delete(self, obj):
+        return super(XOSExampleServiceInstance, self).can_delete(obj)
+