Deprecate GetFromListMixin

This mixin provides a workaround for get() for GitLab objects that don't
implement a 'get a single object' API. We are now getting conflicts
because GitLab adds GET methods, and this is against the "Implement only
what exists in the API" strategy.

Also use the proper GET API call for objects that support it.

2 files changed, 12 insertions, 4 deletions

diff --git a/gitlab/mixins.py b/gitlab/mixins.py
index 88fea2d..d3e5727 100644
--- a/gitlab/mixins.py
+++ b/gitlab/mixins.py
@@ -15,6 +15,8 @@
 # You should have received a copy of the GNU Lesser General Public License
 # along with this program.  If not, see <http://www.gnu.org/licenses/>.
 
+import warnings
+
 import gitlab
 from gitlab import base
 from gitlab import cli
@@ -130,9 +132,13 @@ class ListMixin(object):
 
 
 class GetFromListMixin(ListMixin):
+    """This mixin is deprecated."""
+
     def get(self, id, **kwargs):
         """Retrieve a single object.
 
+        This Method is deprecated.
+
         Args:
             id (int or str): ID of the object to retrieve
             **kwargs: Extra options to send to the Gitlab server (e.g. sudo)
@@ -144,6 +150,9 @@ class GetFromListMixin(ListMixin):
             GitlabAuthenticationError: If authentication is not correct
             GitlabGetError: If the server cannot perform the request
         """
+        warnings.warn('The get() method for this object is deprecated '
+                      'and will be removed in a future version.',
+                       DeprecationWarning)
         try:
             gen = self.list()
         except exc.GitlabListError:
diff --git a/gitlab/v4/objects.py b/gitlab/v4/objects.py
index 1cb8fe7..0e28f5c 100644
--- a/gitlab/v4/objects.py
+++ b/gitlab/v4/objects.py
@@ -547,8 +547,7 @@ class GroupMember(SaveMixin, ObjectDeleteMixin, RESTObject):
     _short_print_attr = 'username'
 
 
-class GroupMemberManager(ListMixin, GetMixin, CreateMixin, UpdateMixin,
-                         DeleteMixin, RESTManager):
+class GroupMemberManager(CRUDMixin, RESTManager):
     _path = '/groups/%(group_id)s/members'
     _obj_cls = GroupMember
     _from_parent_attrs = {'group_id': 'id'}
@@ -822,7 +821,7 @@ class Namespace(RESTObject):
     pass
 
 
-class NamespaceManager(GetFromListMixin, RESTManager):
+class NamespaceManager(RetrieveMixin, RESTManager):
     _path = '/namespaces'
     _obj_cls = Namespace
     _list_filters = ('search', )
@@ -854,7 +853,7 @@ class ProjectBoard(RESTObject):
     _managers = (('lists', 'ProjectBoardListManager'), )
 
 
-class ProjectBoardManager(GetFromListMixin, RESTManager):
+class ProjectBoardManager(RetrieveMixin, RESTManager):
     _path = '/projects/%(project_id)s/boards'
     _obj_cls = ProjectBoard
     _from_parent_attrs = {'project_id': 'id'}