Add uri_segment for MP LB Resources

This patch adds uri_segment as an alias of resource for all MP LB
resources, enabling proper use of _get_resource_by_name_or_id for these
resources.

Change-Id: I548519a8d2ea25d4324060894e0a3a0d03dd7e7e
(cherry picked from commit dd23782b57)

vmware_nsxlib/v3/exceptions.py

@@ -94,6 +94,11 @@ class ResourceNotFound(ManagerError):
                 "%(operation)s")
 
 
+class MultipleResourcesFound(ManagerError):
+    message = _("Multiple resources are found on backend (%(manager)s) for "
+                "%(operation)s, where only one is expected")
+
+
 class BackendResourceNotFound(ResourceNotFound):
     message = _("%(details)s On backend (%(manager)s) with Operation: "
                 "%(operation)s")

vmware_nsxlib/v3/load_balancer.py

@@ -51,6 +51,10 @@ class MonitorTypes(object):
 class LoadBalancerBase(utils.NsxLibApiBase):
     resource = ''
 
+    @property
+    def uri_segment(self):
+        return self.resource
+
     @staticmethod
     def _build_args(body, display_name=None, description=None, tags=None,
                     resource_type=None, **kwargs):

vmware_nsxlib/v3/utils.py

@@ -513,11 +513,11 @@ class NsxLibApiBase(object):
         if len(matched_results) == 0:
             err_msg = (_("Could not find %(resource)s %(name)s") %
                        {'name': name_or_id, 'resource': resource})
-            raise nsxlib_exc.ManagerError(details=err_msg)
+            raise nsxlib_exc.ResourceNotFound(details=err_msg)
         elif len(matched_results) > 1:
             err_msg = (_("Found multiple %(resource)s named %(name)s") %
                        {'name': name_or_id, 'resource': resource})
-            raise nsxlib_exc.ManagerError(details=err_msg)
+            raise nsxlib_exc.MultipleResourcesFound(details=err_msg)
 
         return matched_results[0].get('id')