add reprs to common user-facing classes

sdk/cosmos/azure-cosmos/azure/cosmos/container.py

@@ -67,6 +67,10 @@ def __init__(self, client_connection, database_link, id, properties=None):  # py
         self._is_system_key = None
         self._scripts = None  # type: Optional[ScriptsProxy]
 
+    def __repr__(self):
+        # type () -> str
+        return "<ContainerProxy [{}]>".format(self.container_link)[:1024]
+
     def _get_properties(self):
         # type: () -> Dict[str, Any]
         if self._properties is None:

sdk/cosmos/azure-cosmos/azure/cosmos/cosmos_client.py

@@ -194,6 +194,10 @@ def __init__(self, url, credential, consistency_level="Session", **kwargs):
             url, auth=auth, consistency_level=consistency_level, connection_policy=connection_policy, **kwargs
         )
 
+    def __repr__(self):  # pylint:disable=client-method-name-no-double-underscore
+        # type () -> str
+        return "<CosmosClient [{}]>".format(self.client_connection.url_connection)[:1024]
+
     def __enter__(self):
         self.client_connection.pipeline_client.__enter__()
         return self

sdk/cosmos/azure-cosmos/azure/cosmos/database.py

@@ -76,6 +76,10 @@ def __init__(self, client_connection, id, properties=None):  # pylint: disable=r
         self.database_link = u"dbs/{}".format(self.id)
         self._properties = properties
 
+    def __repr__(self):
+        # type () -> str
+        return "<DatabaseProxy [{}]>".format(self.database_link)[:1024]
+
     @staticmethod
     def _get_container_id(container_or_id):
         # type: (Union[str, ContainerProxy, Dict[str, Any]]) -> str

sdk/cosmos/azure-cosmos/azure/cosmos/partition_key.py

@@ -54,6 +54,10 @@ def __init__(self, path, kind="Hash", version=2):  # pylint: disable=super-init-
         self.kind = kind
         self.version = version
 
+    def __repr__(self):
+        # type () -> str
+        return "<PartitionKey [{}]>".format(self.path)[:1024]
+
     @property
     def kind(self):
         return self["kind"]

sdk/cosmos/azure-cosmos/azure/cosmos/user.py

@@ -47,6 +47,10 @@ def __init__(self, client_connection, id, database_link, properties=None):  # py
         self.user_link = u"{}/users/{}".format(database_link, id)
         self._properties = properties
 
+    def __repr__(self):
+        # type () -> str
+        return "<UserProxy [{}]>".format(self.user_link)[:1024]
+
     def _get_permission_link(self, permission_or_id):
         # type: (Union[Permission, str, Dict[str, Any]]) -> str
         if isinstance(permission_or_id, six.string_types):