Add helpers to detect OpenStack versions

It leverages on Nova API Microversions [1].

[1] https://docs.openstack.org/nova/latest/reference/api-microversion-history.html

Change-Id: I60abf9089036e56fcbcd6c2b734666ea20875ceb
Signed-off-by: Cédric Ollivier <cedric.ollivier@orange.com>

1 files changed, 63 insertions, 1 deletions

diff --git a/functest/utils/functest_utils.py b/functest/utils/functest_utils.py
index b614af321..c5950c965 100644
--- a/functest/utils/functest_utils.py
+++ b/functest/utils/functest_utils.py
@@ -44,7 +44,7 @@ def execute_command(cmd, info=False, error_msg="",
             ofd.write(line)
         else:
             line = line.replace('\n', '')
-            print (line)
+            print(line)
             sys.stdout.flush()
     if output_file:
         ofd.close()
@@ -72,3 +72,65 @@ def get_parameter_from_yaml(parameter, yfile):
             raise ValueError("The parameter %s is not defined in"
                              " %s" % (parameter, yfile))
     return value
+
+
+def get_nova_version(cloud):
+    """ Get Nova API microversion
+
+    Returns:
+
+    - Nova API microversion
+    - None on operation error
+    """
+    # pylint: disable=protected-access
+    try:
+        request = cloud._compute_client.request("/", "GET")
+        LOGGER.debug('cloud._compute_client.request: %s', request)
+        version = request["version"]["version"]
+        major, minor = version.split('.')
+        LOGGER.debug('nova version: %s', (int(major), int(minor)))
+        return (int(major), int(minor))
+    except Exception:  # pylint: disable=broad-except
+        LOGGER.exception("Cannot detect Nova version")
+        return None
+
+
+def get_openstack_version(cloud):
+    """ Detect OpenStack version via Nova API microversion
+
+    It follows MicroversionHistory_.
+
+    Returns:
+
+    - OpenStack release
+    - Unknown on operation error
+
+    .. _MicroversionHistory:
+    https://docs.openstack.org/nova/latest/reference/api-microversion-history.html
+    """
+    version = get_nova_version(cloud)
+    try:
+        assert version
+        if version > (2, 60):
+            osversion = "Rocky or newer"
+        elif version > (2, 53):
+            osversion = "Queens"
+        elif version > (2, 42):
+            osversion = "Pike"
+        elif version > (2, 38):
+            osversion = "Ocata"
+        elif version > (2, 25):
+            osversion = "Newton"
+        elif version > (2, 12):
+            osversion = "Mitaka"
+        elif version > (2, 3):
+            osversion = "Liberty"
+        elif version >= (2, 1):
+            osversion = "Kilo"
+        else:
+            osversion = "Unknown"
+        LOGGER.info('Detect OpenStack version: %s', osversion)
+        return osversion
+    except AssertionError:
+        LOGGER.exception("Cannot detect OpenStack version")
+        return "Unknown"