Microversion 2.91: Support specifying destination host to unshelve

This patch adds ``host`` to openstacksdk unshelve api.
This can help administrators to specify a ``host``
to unshelve a shelve offloaded server starting from 2.91 microversion.

Implements: blueprint unshelve-to-host
Change-Id: I34c5989be4710c863cce24d6f55bd1faae86cd52

openstack/compute/v2/server.py

@@ -40,6 +40,11 @@ class Server(resource.Resource, metadata.MetadataMixin, tag.TagMixin):
     allow_delete = True
     allow_list = True
 
+    # Sentinel used to differentiate API called without parameter or None
+    # Ex unshelve API can be called without an availability_zone or with
+    # availability_zone = None to unpin the az.
+    _sentinel = object()
+
     _query_mapping = resource.QueryParameters(
         "auto_disk_config", "availability_zone",
         "created_at", "description", "flavor",
@@ -65,7 +70,7 @@ class Server(resource.Resource, metadata.MetadataMixin, tag.TagMixin):
         **tag.TagMixin._tag_query_parameters
     )
 
-    _max_microversion = '2.73'
+    _max_microversion = '2.91'
 
     #: A list of dictionaries holding links relevant to this server.
     links = resource.Body('links')
@@ -497,10 +502,26 @@ class Server(resource.Resource, metadata.MetadataMixin, tag.TagMixin):
         body = {"shelve": None}
         self._action(session, body)
 
-    def unshelve(self, session, availability_zone=None):
-        body = {"unshelve": None}
-        if availability_zone:
-            body["unshelve"] = {"availability_zone": availability_zone}
+    def unshelve(self, session, availability_zone=_sentinel, host=None):
+        """
+        Unshelve -- Unshelve the server.
+
+        :param availability_zone: If specified the instance will be unshelved
+            to the availability_zone.
+            If None is passed the instance defined availability_zone is unpin
+            and the instance will be scheduled to any availability_zone (free
+            scheduling).
+            If not specified the instance will be unshelved to either its
+            defined availability_zone or any availability_zone
+            (free scheduling).
+        :param host: If specified the host to unshelve the instance.
+        """
+        data = {}
+        if host:
+            data["host"] = host
+        if availability_zone is None or isinstance(availability_zone, str):
+            data["availability_zone"] = availability_zone
+        body = {'unshelve': data or None}
         self._action(session, body)
 
     def migrate(self, session):

openstack/tests/unit/compute/v2/test_server.py

@@ -893,6 +893,56 @@ class TestServer(base.TestCase):
             microversion=self.sess.default_microversion,
         )
 
+    def test_unshelve_unpin_az(self):
+        sot = server.Server(**EXAMPLE)
+
+        res = sot.unshelve(self.sess, availability_zone=None)
+
+        self.assertIsNone(res)
+        url = 'servers/IDENTIFIER/action'
+        body = {"unshelve": {
+            "availability_zone": None
+        }}
+        headers = {'Accept': ''}
+        self.sess.post.assert_called_with(
+            url, json=body, headers=headers,
+            microversion=self.sess.default_microversion)
+
+    def test_unshelve_host(self):
+        sot = server.Server(**EXAMPLE)
+
+        res = sot.unshelve(self.sess, host=sot.hypervisor_hostname)
+
+        self.assertIsNone(res)
+        url = 'servers/IDENTIFIER/action'
+        body = {"unshelve": {
+            "host": sot.hypervisor_hostname
+        }}
+        headers = {'Accept': ''}
+        self.sess.post.assert_called_with(
+            url, json=body, headers=headers,
+            microversion=self.sess.default_microversion)
+
+    def test_unshelve_host_and_availability_zone(self):
+        sot = server.Server(**EXAMPLE)
+
+        res = sot.unshelve(
+            self.sess,
+            availability_zone=sot.availability_zone,
+            host=sot.hypervisor_hostname
+        )
+
+        self.assertIsNone(res)
+        url = 'servers/IDENTIFIER/action'
+        body = {"unshelve": {
+            "availability_zone": sot.availability_zone,
+            "host": sot.hypervisor_hostname
+        }}
+        headers = {'Accept': ''}
+        self.sess.post.assert_called_with(
+            url, json=body, headers=headers,
+            microversion=self.sess.default_microversion)
+
     def test_migrate(self):
         sot = server.Server(**EXAMPLE)
 

releasenotes/notes/unshelve-to-specific-host-84666d440dce4a73.yaml

@@ -0,0 +1,7 @@
+---
+features:
+  - |
+    Add SDK support for Nova microversion 2.91. This microversion
+    allows specifying a destination host to unshelve a shelve
+    offloaded server. And availability zone can be set to None to unpin
+    the availability zone of a server.