Remove use of distutils

This has been removed in Python 3.12, which is preventing us using
ironicclient in those environments. Thankfully we only use it for
StrictVersion which we are using to parse microversions. This is
actually overkill here since we can always expect a version string like
'1.5', thus we do this parsing ourselves rather than drag in a new
library like 'microversion_parse'.

Change-Id: I7630ecfa2797c502868994302926bd2ac07d1ff7
Signed-off-by: Stephen Finucane <stephenfin@redhat.com>

ironicclient/common/http.py

@@ -13,7 +13,6 @@
 #    License for the specific language governing permissions and limitations
 #    under the License.
 
-from distutils.version import StrictVersion
 import functools
 from http import client as http_client
 import json
@@ -48,17 +47,36 @@ _MAJOR_VERSION = 1
 API_VERSION = '/v%d' % _MAJOR_VERSION
 API_VERSION_SELECTED_STATES = ('user', 'negotiated', 'cached', 'default')
 
-
 DEFAULT_MAX_RETRIES = 5
 DEFAULT_RETRY_INTERVAL = 2
 SENSITIVE_HEADERS = ('X-Auth-Token',)
 
-
 SUPPORTED_ENDPOINT_SCHEME = ('http', 'https')
 
 _API_VERSION_RE = re.compile(r'/+(v%d)?/*$' % _MAJOR_VERSION)
 
 
+@functools.total_ordering
+class _Version:
+    _version_re = re.compile(r'^(\d) \. (\d+)$', re.VERBOSE | re.ASCII)
+
+    def __init__(self, version):
+        match = self._version_re.match(version)
+        if not match:
+            raise ValueError('invalid version number %s' % version)
+        major, minor = match.group(1, 2)
+        self.version = (int(major), int(minor))
+
+    def __str__(self):
+        return '.'.join(str(v) for v in self.version)
+
+    def __eq__(self, other):
+        return self.version == other.version
+
+    def __lt__(self, other):
+        return self.version < other.version
+
+
 def _trim_endpoint_api_version(url):
     """Trim API version and trailing slash from endpoint."""
     return re.sub(_API_VERSION_RE, '', url)
@@ -159,7 +177,8 @@ class VersionNegotiationMixin(object):
             resp = _query_server(conn)
             min_ver, max_ver = self._parse_version_headers(resp)
         # Reset the maximum version that we permit
-        if StrictVersion(max_ver) > StrictVersion(LATEST_VERSION):
+
+        if _Version(max_ver) > _Version(LATEST_VERSION):
             LOG.debug("Remote API version %(max_ver)s is greater than the "
                       "version supported by ironicclient. Maximum available "
                       "version is %(client_ver)s",
@@ -198,8 +217,8 @@ class VersionNegotiationMixin(object):
                 negotiated_ver = max_ver
             else:
                 negotiated_ver = str(
-                    min(StrictVersion(requested_version),
+                    min(_Version(requested_version), _Version(max_ver))
-                        StrictVersion(max_ver)))
+                )
 
         elif isinstance(requested_version, list):
             if 'latest' in requested_version:
@@ -212,8 +231,8 @@ class VersionNegotiationMixin(object):
 
             versions = []
             for version in requested_version:
-                if min_ver <= StrictVersion(version) <= max_ver:
+                if _Version(min_ver) <= _Version(version) <= _Version(max_ver):
-                    versions.append(StrictVersion(version))
+                    versions.append(_Version(version))
             if versions:
                 negotiated_ver = str(max(versions))
             else:
@@ -232,8 +251,9 @@ class VersionNegotiationMixin(object):
                   "or a list of string values representing API versions.")
                 % {'req': requested_version}))
 
-        if StrictVersion(negotiated_ver) < StrictVersion(min_ver):
+        if _Version(negotiated_ver) < _Version(min_ver):
             negotiated_ver = min_ver
+
         # server handles microversions, but doesn't support
         # the requested version, so try a negotiated version
         self.api_version_select_state = 'negotiated'
@@ -248,10 +268,8 @@ class VersionNegotiationMixin(object):
         return negotiated_ver
 
     def _generic_parse_version_headers(self, accessor_func):
-        min_ver = accessor_func('X-OpenStack-Ironic-API-Minimum-Version',
+        min_ver = accessor_func('X-OpenStack-Ironic-API-Minimum-Version', None)
-                                None)
+        max_ver = accessor_func('X-OpenStack-Ironic-API-Maximum-Version', None)
-        max_ver = accessor_func('X-OpenStack-Ironic-API-Maximum-Version',
-                                None)
         return min_ver, max_ver
 
     def _parse_version_headers(self, accessor_func):

ironicclient/tests/unit/common/test_http.py

@@ -232,7 +232,7 @@ class VersionNegotiationMixinTest(utils.BaseTestCase):
         mock_conn = mock.MagicMock()
         self.test_object.api_version_select_state = 'user'
         self.test_object.os_ironic_api_version = ['1.1', '1.6', '1.25',
-                                                  '1.26', '1.26.1', '1.27',
+                                                  '1.26', '1.27', '1.28',
                                                   '1.30']
         result = self.test_object.negotiate_version(mock_conn, self.response)
         self.assertEqual('1.26', result)