Set DEFAULT_OS_COMPUTE_API_VERSION to 2.5

The client currently implements support for microversions 2.2, 2.4 and
2.11.

According the nova API microversion history:

http://docs.openstack.org/developer/nova/api_microversion_history.html

2.3 just returns extra attributes in the response so it's not a problem
for the client. We should expose those at some point but it's not a
breaking change.

2.5 is a server-side only change since the client allows filtering
servers by IPv6 address but the server wasn't honoring that until 2.5.
There are no client side changes for that microversion.

2.6 is the first backwards incompatible microversion since it replaces
the old specific console APIs (RDP/serial/SPICE/VNC) with a new generic
remote-consoles API. The client must be updated to handle this since
requesting any microversion >=2.6 for consoles will fail right now. This
is exposed on the CLI right now because the CLI defaults to the 2.latest
microversion.

So even though the client actually supports the 2.11 microversion, we
shouldn't default to higher than 2.5 because we have gaps in handling
2.6->2.10.

This change fixes the default for the CLI by setting
DEFAULT_OS_COMPUTE_API_VERSION=2.5.

Partial-Bug: #1500688

Change-Id: I52074f9a3e7faa6a7a51c3fa9766100acf25dee2
(cherry picked from commit d045019f0f)

------------------------------------------------------------------------
The first change introduced a regression which is fixed in the following
squashed change to make the complete fix.
------------------------------------------------------------------------

Correct usage of API_MAX_VERSION and DEFAULT_OS_COMPUTE_API_VERSION

Commit d045019f0f use the variables
API_MAX_VERSION and DEFAULT_OS_COMPUTE_API_VERSION with wrong way.

API_MAX_VERSION means the max version of client supported. This
variable only be changed when client support the new version. And
it's must bumped sequentially.

DEFAULT_OS_COMPUTE_API_VERSION is default value of option
'--os-compute-api-version', this value decided the default behaviour
of nova client. The nova client CLI behaviour should be that client
negotiate with server side to find out most recent version betweeyn
client and server. So the value should be '2.latest'. And it won't
be changed except we decided to change the default behaviour of nova
client CLI.

Change-Id: Iba9bfa136245bd2899c427ac0c231a30c00bd7f3
Closes-Bug: #1508244
(cherry picked from commit 28bf8ddb06)

novaclient/__init__.py

@@ -20,4 +20,9 @@ from novaclient import api_versions
 __version__ = pbr.version.VersionInfo('python-novaclient').version_string()
 
 API_MIN_VERSION = api_versions.APIVersion("2.1")
-API_MAX_VERSION = api_versions.APIVersion("2.11")
+# The max version should be the latest version that is supported in the client,
+# not necessarily the latest that the server can provide. This is only bumped
+# when client supported the max version, and bumped sequentially, otherwise
+# the client may break due to server side new version may include some
+# backward incompatible change.
+API_MAX_VERSION = api_versions.APIVersion("2.5")

novaclient/shell.py

@@ -51,7 +51,11 @@ from novaclient.openstack.common import cliutils
 from novaclient import utils
 
 DEFAULT_MAJOR_OS_COMPUTE_API_VERSION = "2.0"
-DEFAULT_OS_COMPUTE_API_VERSION = "2.latest"
+# The default behaviour of nova client CLI is that CLI negotiates with server
+# to find out the most recent version between client and server, and
+# '2.latest' means to that. This value never be changed until we decided to
+# change the default behaviour of nova client CLI.
+DEFAULT_OS_COMPUTE_API_VERSION = '2.latest'
 DEFAULT_NOVA_ENDPOINT_TYPE = 'publicURL'
 DEFAULT_NOVA_SERVICE_TYPE = "compute"
 

novaclient/tests/unit/test_shell.py

@@ -65,6 +65,12 @@ FAKE_ENV5 = {'OS_USERNAME': 'username',
              'OS_COMPUTE_API_VERSION': '2',
              'OS_AUTH_SYSTEM': 'rackspace'}
 
+FAKE_ENV6 = {'OS_USERNAME': 'username',
+             'OS_PASSWORD': 'password',
+             'OS_TENANT_NAME': 'tenant_name',
+             'OS_AUTH_URL': 'http://no.where/v2.0',
+             'OS_AUTH_SYSTEM': 'rackspace'}
+
 
 def _create_ver_list(versions):
     return {'versions': {'values': versions}}
@@ -424,6 +430,25 @@ class ShellTest(utils.TestCase):
         keyring_saver = mock_client_instance.client.keyring_saver
         self.assertIsInstance(keyring_saver, novaclient.shell.SecretsHelper)
 
+    @mock.patch('novaclient.client.Client')
+    def test_microversion_with_default_behaviour(self, mock_client):
+        self.make_env(fake_env=FAKE_ENV6)
+        self.mock_server_version_range.return_value = (
+            api_versions.APIVersion("2.1"), api_versions.APIVersion("2.3"))
+        self.shell('list')
+        client_args = mock_client.call_args_list[1][0]
+        self.assertEqual(api_versions.APIVersion("2.3"), client_args[0])
+
+    @mock.patch('novaclient.client.Client')
+    def test_microversion_with_default_behaviour_with_legacy_server(
+            self, mock_client):
+        self.make_env(fake_env=FAKE_ENV6)
+        self.mock_server_version_range.return_value = (
+            api_versions.APIVersion(), api_versions.APIVersion())
+        self.shell('list')
+        client_args = mock_client.call_args_list[1][0]
+        self.assertEqual(api_versions.APIVersion("2.0"), client_args[0])
+
     @mock.patch('novaclient.client.Client')
     def test_microversion_with_latest(self, mock_client):
         self.make_env()