Make instance_uuid optional in attachment create

Cinder and cinderclient assumes an attachment create request will
always contain instance_uuid. This is not true when glance calls
cinder for attachment in glance cinder configuration.
This patch (along with the cinder patch) make the instance_uuid
optional and allow glance to do attachments without passing
instance_uuid.

Change-Id: Ifbaca4aa87d890bc5130069638d42665b914b378

cinderclient/tests/unit/v3/fakes.py

@@ -29,6 +29,16 @@ fake_attachment = {'attachment': {
     'instance': 'e84fda45-4de4-4ce4-8f39-fc9d3b0aa05e',
     'volume_id': '557ad76c-ce54-40a3-9e91-c40d21665cc3', }}
 
+fake_attachment_without_instance_id = {'attachment': {
+    'status': 'reserved',
+    'detached_at': '',
+    'connection_info': {},
+    'attached_at': '',
+    'attach_mode': None,
+    'id': 'a232e9ae',
+    'instance': None,
+    'volume_id': '557ad76c-ce54-40a3-9e91-c40d21665cc3', }}
+
 fake_attachment_list = {'attachments': [
     {'instance': 'instance_1',
      'name': 'attachment-1',
@@ -297,7 +307,9 @@ class FakeHTTPClient(fake_v2.FakeHTTPClient):
     #
 
     def post_attachments(self, **kw):
+        if kw['body']['attachment'].get('instance_uuid'):
             return (200, {}, fake_attachment)
+        return (200, {}, fake_attachment_without_instance_id)
 
     def get_attachments(self, **kw):
         return (200, {}, fake_attachment_list)

cinderclient/tests/unit/v3/test_attachments.py

@@ -31,6 +31,17 @@ class AttachmentsTest(utils.TestCase):
         cs.assert_called('POST', '/attachments')
         self.assertEqual(fakes.fake_attachment['attachment'], att)
 
+    def test_create_attachment_without_instance_uuid(self):
+        cs = fakes.FakeClient(api_versions.APIVersion('3.27'))
+        att = cs.attachments.create(
+            'e84fda45-4de4-4ce4-8f39-fc9d3b0aa05e',
+            {},
+            None,
+            'null')
+        cs.assert_called('POST', '/attachments')
+        self.assertEqual(
+            fakes.fake_attachment_without_instance_id['attachment'], att)
+
     def test_complete_attachment(self):
         cs = fakes.FakeClient(api_versions.APIVersion('3.44'))
         att = cs.attachments.complete('a232e9ae')

cinderclient/tests/unit/v3/test_shell.py

@@ -388,6 +388,25 @@ class ShellTest(utils.TestCase):
               {'cmd': 'abc 1233',
                'body': {'instance_uuid': '1233',
                         'connector': {},
+                        'volume_uuid': '1234'}},
+              {'cmd': '1234',
+               'body': {'connector': {},
+                        'volume_uuid': '1234'}},
+              {'cmd': '1234 '
+                      '--connect True '
+                      '--ip 10.23.12.23 --host server01 '
+                      '--platform x86_xx '
+                      '--ostype 123 '
+                      '--multipath true '
+                      '--mountpoint /123 '
+                      '--initiator aabbccdd',
+               'body': {'connector': {'ip': '10.23.12.23',
+                                      'host': 'server01',
+                                      'os_type': '123',
+                                      'multipath': 'true',
+                                      'mountpoint': '/123',
+                                      'initiator': 'aabbccdd',
+                                      'platform': 'x86_xx'},
                         'volume_uuid': '1234'}})
     @mock.patch('cinderclient.utils.find_resource')
     @ddt.unpack
@@ -429,6 +448,27 @@ class ShellTest(utils.TestCase):
                'body': {'instance_uuid': '1233',
                         'connector': {},
                         'volume_uuid': '1234',
+                        'mode': 'ro'}},
+              {'cmd': '1234',
+               'body': {'connector': {},
+                        'volume_uuid': '1234',
+                        'mode': 'ro'}},
+              {'cmd': '1234 '
+                      '--connect True '
+                      '--ip 10.23.12.23 --host server01 '
+                      '--platform x86_xx '
+                      '--ostype 123 '
+                      '--multipath true '
+                      '--mountpoint /123 '
+                      '--initiator aabbccdd',
+               'body': {'connector': {'ip': '10.23.12.23',
+                                      'host': 'server01',
+                                      'os_type': '123',
+                                      'multipath': 'true',
+                                      'mountpoint': '/123',
+                                      'initiator': 'aabbccdd',
+                                      'platform': 'x86_xx'},
+                        'volume_uuid': '1234',
                         'mode': 'ro'}})
     @mock.patch('cinderclient.utils.find_resource')
     @ddt.unpack

cinderclient/v3/attachments.py

@@ -27,11 +27,12 @@ class VolumeAttachmentManager(base.ManagerWithFind):
     resource_class = VolumeAttachment
 
     @api_versions.wraps('3.27')
-    def create(self, volume_id, connector, instance_id, mode='null'):
+    def create(self, volume_id, connector, instance_id=None, mode='null'):
         """Create a attachment for specified volume."""
         body = {'attachment': {'volume_uuid': volume_id,
-                               'instance_uuid': instance_id,
                                'connector': connector}}
+        if instance_id:
+            body['attachment']['instance_uuid'] = instance_id
         if self.api_version >= api_versions.APIVersion("3.54"):
             if mode and mode != 'null':
                 body['attachment']['mode'] = mode

cinderclient/v3/shell.py

@@ -2297,6 +2297,8 @@ def do_attachment_show(cs, args):
            help='Name or ID of volume or volumes to attach.')
 @utils.arg('server_id',
            metavar='<server_id>',
+           nargs='?',
+           default=None,
            help='ID of server attaching to.')
 @utils.arg('--connect',
            metavar='<connect>',

releasenotes/notes/attachment-create-optional-server-id-9299d9da2b62b263.yaml

@@ -0,0 +1,10 @@
+---
+fixes:
+  - |
+    When attaching to a host, we don't need a server id
+    so it shouldn't be mandatory to be supplied with
+    attachment-create operation.
+    The server_id parameter is made optional so we can
+    create attachments without passing it.
+    The backward compatibility is maintained so we can pass
+    it like how we currently do if required.