Merge "Add System<->Manager linkage"

releasenotes/notes/add-system-manager-linkage-86be69c9df4cb359.yaml

@@ -0,0 +1,6 @@
+---
+features:
+  - |
+    Establishes ComputerSystem->Managers and Manager->ComputerSystems
+    references at sushy data abstraction level what make it possible to
+    look up Manager(s) responsible for a ComputerSystem and vice versa.

sushy/resources/manager/manager.py

@@ -195,6 +195,25 @@ class Manager(base.ResourceBase):
             self._conn, utils.get_sub_resource_path_by(self, 'VirtualMedia'),
             redfish_version=self.redfish_version)
 
+    @property
+    @utils.cache_it
+    def systems(self):
+        """A list of systems managed by this manager.
+
+        Returns a list of `System` objects representing systems being
+        managed by this manager.
+
+        :raises: MissingAttributeError if '@odata.id' field is missing.
+        :returns: A list of `System` instances
+        """
+        paths = utils.get_sub_resource_path_by(
+            self, ["Links", "ManagerForServers"], is_collection=True)
+
+        from sushy.resources.system import system
+        return [system.System(self._conn, path,
+                              redfish_version=self.redfish_version)
+                for path in paths]
+
 
 class ManagerCollection(base.ResourceCollectionBase):
 

sushy/resources/system/system.py

@@ -21,6 +21,7 @@ import logging
 from sushy import exceptions
 from sushy.resources import base
 from sushy.resources import common
+from sushy.resources.manager import manager
 from sushy.resources import mappings as res_maps
 from sushy.resources.system import bios
 from sushy.resources.system import constants as sys_cons
@@ -336,6 +337,24 @@ class System(base.ResourceBase):
             self._conn, utils.get_sub_resource_path_by(self, "Storage"),
             redfish_version=self.redfish_version)
 
+    @property
+    @utils.cache_it
+    def managers(self):
+        """A list of managers for this system.
+
+        Returns a list of `Manager` objects representing the managers
+        that manage this system.
+
+        :raises: MissingAttributeError if '@odata.id' field is missing.
+        :returns: A list of `Manager` instances
+        """
+        paths = utils.get_sub_resource_path_by(
+            self, ["Links", "ManagedBy"], is_collection=True)
+
+        return [manager.Manager(self._conn, path,
+                                redfish_version=self.redfish_version)
+                for path in paths]
+
 
 class SystemCollection(base.ResourceCollectionBase):
 

sushy/tests/unit/resources/manager/test_manager.py

@@ -18,6 +18,7 @@ import sushy
 from sushy import exceptions
 from sushy.resources.manager import manager
 from sushy.resources.manager import virtual_media
+from sushy.resources.system import system
 from sushy.tests.unit import base
 
 
@@ -266,6 +267,18 @@ class ManagerTestCase(base.TestCase):
                               virtual_media.VirtualMediaCollection)
         self.assertFalse(vrt_media._is_stale)
 
+    def test_systems(self):
+        # | GIVEN |
+        with open('sushy/tests/unit/json_samples/'
+                  'system.json') as f:
+            self.conn.get.return_value.json.return_value = json.load(f)
+
+        # | WHEN & THEN |
+        actual_systems = self.manager.systems
+        self.assertIsInstance(actual_systems[0], system.System)
+        self.assertEqual(
+            '/redfish/v1/Systems/437XR1138R2', actual_systems[0].path)
+
 
 class ManagerCollectionTestCase(base.TestCase):
 

sushy/tests/unit/resources/system/test_system.py

@@ -20,6 +20,7 @@ import mock
 import sushy
 from sushy import exceptions
 from sushy.resources import constants as res_cons
+from sushy.resources.manager import manager
 from sushy.resources.system import bios
 from sushy.resources.system import mappings as sys_map
 from sushy.resources.system import processor
@@ -478,6 +479,18 @@ class SystemTestCase(base.TestCase):
         # | WHEN & THEN |
         self.assertIsInstance(self.sys_inst.storage, storage.StorageCollection)
 
+    def test_managers(self):
+        # | GIVEN |
+        with open('sushy/tests/unit/json_samples/'
+                  'manager.json') as f:
+            self.conn.get.return_value.json.return_value = json.load(f)
+
+        # | WHEN & THEN |
+        actual_managers = self.sys_inst.managers
+        self.assertIsInstance(actual_managers[0], manager.Manager)
+        self.assertEqual(
+            '/redfish/v1/Managers/BMC', actual_managers[0].path)
+
 
 class SystemCollectionTestCase(base.TestCase):
 

sushy/tests/unit/test_utils.py

@@ -69,6 +69,14 @@ class UtilsTestCase(base.TestCase):
                                                subresource_path)
         self.assertEqual(expected_result, value)
 
+    def test_get_sub_resource_path_by_collection(self):
+        subresource_path = ["Links", "ManagedBy"]
+        expected_result = ['/redfish/v1/Managers/BMC']
+        value = utils.get_sub_resource_path_by(self.sys_inst,
+                                               subresource_path,
+                                               is_collection=True)
+        self.assertEqual(expected_result, value)
+
     def test_get_sub_resource_path_by_fails(self):
         subresource_path = ['Links', 'Chassis']
         expected_result = 'attribute Links/Chassis/@odata.id is missing'

sushy/utils.py

@@ -66,13 +66,17 @@ def int_or_none(x):
     return int(x)
 
 
-def get_sub_resource_path_by(resource, subresource_name):
+def get_sub_resource_path_by(resource, subresource_name, is_collection=False):
     """Helper function to find the subresource path
 
     :param resource: ResourceBase instance on which the name
         gets queried upon.
     :param subresource_name: name of the resource field to
         fetch the '@odata.id' from.
+    :param is_collection: if `True`, expect a list of resources to
+        fetch the '@odata.id' from.
+    :returns: Resource path (if `is_collection` is `False`) or
+        a list of resource paths (if `is_collection` is `True`).
     """
     if not subresource_name:
         raise ValueError('"subresource_name" cannot be empty')
@@ -88,12 +92,24 @@ def get_sub_resource_path_by(resource, subresource_name):
         raise exceptions.MissingAttributeError(
             attribute='/'.join(subresource_name), resource=resource.path)
 
-    if '@odata.id' not in body:
-        raise exceptions.MissingAttributeError(
-            attribute='/'.join(subresource_name) + '/@odata.id',
-            resource=resource.path)
+    elements = []
 
-    return body['@odata.id']
+    try:
+        if is_collection:
+            for element in body:
+                elements.append(element['@odata.id'])
+            return elements
+
+        else:
+            return body['@odata.id']
+
+    except (TypeError, KeyError):
+        attribute = '/'.join(subresource_name)
+        if is_collection:
+            attribute += '[%s]' % len(elements)
+        attribute += '/@odata.id'
+        raise exceptions.MissingAttributeError(
+            attribute=attribute, resource=resource.path)
 
 
 def max_safe(iterable, default=0):