python-novaclient/novaclient/api_versions.py

357 lines
13 KiB
Python

#
# Licensed under the Apache License, Version 2.0 (the "License"); you may
# not use this file except in compliance with the License. You may obtain
# a copy of the License at
#
# http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
# WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
# License for the specific language governing permissions and limitations
# under the License.
import functools
import logging
import os
import pkgutil
import re
from oslo_utils import strutils
import novaclient
from novaclient import exceptions
from novaclient.i18n import _, _LW
from novaclient.openstack.common import cliutils
from novaclient import utils
LOG = logging.getLogger(__name__)
if not LOG.handlers:
LOG.addHandler(logging.StreamHandler())
# key is a deprecated version and value is an alternative version.
DEPRECATED_VERSIONS = {"1.1": "2"}
_SUBSTITUTIONS = {}
_type_error_msg = _("'%(other)s' should be an instance of '%(cls)s'")
class APIVersion(object):
"""This class represents an API Version with convenience
methods for manipulation and comparison of version
numbers that we need to do to implement microversions.
"""
def __init__(self, version_str=None):
"""Create an API version object."""
self.ver_major = 0
self.ver_minor = 0
if version_str is not None:
match = re.match(r"^([1-9]\d*)\.([1-9]\d*|0|latest)$", version_str)
if match:
self.ver_major = int(match.group(1))
if match.group(2) == "latest":
# NOTE(andreykurilin): Infinity allows to easily determine
# latest version and doesn't require any additional checks
# in comparison methods.
self.ver_minor = float("inf")
else:
self.ver_minor = int(match.group(2))
else:
msg = _("Invalid format of client version '%s'. "
"Expected format 'X.Y', where X is a major part and Y "
"is a minor part of version.") % version_str
raise exceptions.UnsupportedVersion(msg)
def __str__(self):
"""Debug/Logging representation of object."""
if self.is_latest():
return "Latest API Version Major: %s" % self.ver_major
return ("API Version Major: %s, Minor: %s"
% (self.ver_major, self.ver_minor))
def __repr__(self):
if self.is_null():
return "<APIVersion: null>"
else:
return "<APIVersion: %s>" % self.get_string()
def is_null(self):
return self.ver_major == 0 and self.ver_minor == 0
def is_latest(self):
return self.ver_minor == float("inf")
def __lt__(self, other):
if not isinstance(other, APIVersion):
raise TypeError(_type_error_msg % {"other": other,
"cls": self.__class__})
return ((self.ver_major, self.ver_minor) <
(other.ver_major, other.ver_minor))
def __eq__(self, other):
if not isinstance(other, APIVersion):
raise TypeError(_type_error_msg % {"other": other,
"cls": self.__class__})
return ((self.ver_major, self.ver_minor) ==
(other.ver_major, other.ver_minor))
def __gt__(self, other):
if not isinstance(other, APIVersion):
raise TypeError(_type_error_msg % {"other": other,
"cls": self.__class__})
return ((self.ver_major, self.ver_minor) >
(other.ver_major, other.ver_minor))
def __le__(self, other):
return self < other or self == other
def __ne__(self, other):
return not self.__eq__(other)
def __ge__(self, other):
return self > other or self == other
def matches(self, min_version, max_version):
"""Returns whether the version object represents a version
greater than or equal to the minimum version and less than
or equal to the maximum version.
:param min_version: Minimum acceptable version.
:param max_version: Maximum acceptable version.
:returns: boolean
If min_version is null then there is no minimum limit.
If max_version is null then there is no maximum limit.
If self is null then raise ValueError
"""
if self.is_null():
raise ValueError(_("Null APIVersion doesn't support 'matches'."))
if max_version.is_null() and min_version.is_null():
return True
elif max_version.is_null():
return min_version <= self
elif min_version.is_null():
return self <= max_version
else:
return min_version <= self <= max_version
def get_string(self):
"""Converts object to string representation which if used to create
an APIVersion object results in the same version.
"""
if self.is_null():
raise ValueError(
_("Null APIVersion cannot be converted to string."))
elif self.is_latest():
return "%s.%s" % (self.ver_major, "latest")
return "%s.%s" % (self.ver_major, self.ver_minor)
class VersionedMethod(object):
def __init__(self, name, start_version, end_version, func):
"""Versioning information for a single method
:param name: Name of the method
:param start_version: Minimum acceptable version
:param end_version: Maximum acceptable_version
:param func: Method to call
Minimum and maximums are inclusive
"""
self.name = name
self.start_version = start_version
self.end_version = end_version
self.func = func
def __str__(self):
return ("Version Method %s: min: %s, max: %s"
% (self.name, self.start_version, self.end_version))
def __repr__(self):
return "<VersionedMethod %s>" % self.name
def get_available_major_versions():
# NOTE(andreykurilin): available clients version should not be
# hardcoded, so let's discover them.
matcher = re.compile(r"v[0-9]*$")
submodules = pkgutil.iter_modules([os.path.dirname(__file__)])
available_versions = [name[1:] for loader, name, ispkg in submodules
if matcher.search(name)]
return available_versions
def check_major_version(api_version):
"""Checks major part of ``APIVersion`` obj is supported.
:raises novaclient.exceptions.UnsupportedVersion: if major part is not
supported
"""
available_versions = get_available_major_versions()
if (not api_version.is_null() and
str(api_version.ver_major) not in available_versions):
if len(available_versions) == 1:
msg = _("Invalid client version '%(version)s'. "
"Major part should be '%(major)s'") % {
"version": api_version.get_string(),
"major": available_versions[0]}
else:
msg = _("Invalid client version '%(version)s'. "
"Major part must be one of: '%(major)s'") % {
"version": api_version.get_string(),
"major": ", ".join(available_versions)}
raise exceptions.UnsupportedVersion(msg)
def get_api_version(version_string):
"""Returns checked APIVersion object"""
version_string = str(version_string)
if version_string in DEPRECATED_VERSIONS:
LOG.warning(
_LW("Version %(deprecated_version)s is deprecated, using "
"alternative version %(alternative)s instead.") %
{"deprecated_version": version_string,
"alternative": DEPRECATED_VERSIONS[version_string]})
version_string = DEPRECATED_VERSIONS[version_string]
if strutils.is_int_like(version_string):
version_string = "%s.0" % version_string
api_version = APIVersion(version_string)
check_major_version(api_version)
return api_version
def _get_server_version_range(client):
version = client.versions.get_current()
if not hasattr(version, 'version') or not version.version:
return APIVersion(), APIVersion()
return APIVersion(version.min_version), APIVersion(version.version)
def discover_version(client, requested_version):
"""Checks ``requested_version`` and returns the most recent version
supported by both the API and the client.
:param client: client object
:param requested_version: requested version represented by APIVersion obj
:returns: APIVersion
"""
server_start_version, server_end_version = _get_server_version_range(
client)
if (not requested_version.is_latest() and
requested_version != APIVersion('2.0')):
if server_start_version.is_null() and server_end_version.is_null():
raise exceptions.UnsupportedVersion(
_("Server doesn't support microversions"))
if not requested_version.matches(server_start_version,
server_end_version):
raise exceptions.UnsupportedVersion(
_("The specified version isn't supported by server. The valid "
"version range is '%(min)s' to '%(max)s'") % {
"min": server_start_version.get_string(),
"max": server_end_version.get_string()})
return requested_version
if requested_version == APIVersion('2.0'):
if (server_start_version == APIVersion('2.1') or
(server_start_version.is_null() and
server_end_version.is_null())):
return APIVersion('2.0')
else:
raise exceptions.UnsupportedVersion(
_("The server isn't backward compatible with Nova V2 REST "
"API"))
if server_start_version.is_null() and server_end_version.is_null():
return APIVersion('2.0')
elif novaclient.API_MIN_VERSION > server_end_version:
raise exceptions.UnsupportedVersion(
_("Server version is too old. The client valid version range is "
"'%(client_min)s' to '%(client_max)s'. The server valid version "
"range is '%(server_min)s' to '%(server_max)s'.") % {
'client_min': novaclient.API_MIN_VERSION.get_string(),
'client_max': novaclient.API_MAX_VERSION.get_string(),
'server_min': server_start_version.get_string(),
'server_max': server_end_version.get_string()})
elif novaclient.API_MAX_VERSION < server_start_version:
raise exceptions.UnsupportedVersion(
_("Server version is too new. The client valid version range is "
"'%(client_min)s' to '%(client_max)s'. The server valid version "
"range is '%(server_min)s' to '%(server_max)s'.") % {
'client_min': novaclient.API_MIN_VERSION.get_string(),
'client_max': novaclient.API_MAX_VERSION.get_string(),
'server_min': server_start_version.get_string(),
'server_max': server_end_version.get_string()})
elif novaclient.API_MAX_VERSION <= server_end_version:
return novaclient.API_MAX_VERSION
elif server_end_version < novaclient.API_MAX_VERSION:
return server_end_version
def update_headers(headers, api_version):
"""Set 'X-OpenStack-Nova-API-Version' header if api_version is not null"""
if not api_version.is_null() and api_version.ver_minor != 0:
headers["X-OpenStack-Nova-API-Version"] = api_version.get_string()
def add_substitution(versioned_method):
_SUBSTITUTIONS.setdefault(versioned_method.name, [])
_SUBSTITUTIONS[versioned_method.name].append(versioned_method)
def get_substitutions(func_name, api_version=None):
substitutions = _SUBSTITUTIONS.get(func_name, [])
if api_version and not api_version.is_null():
return [m for m in substitutions
if api_version.matches(m.start_version, m.end_version)]
return substitutions
def wraps(start_version, end_version=None):
start_version = APIVersion(start_version)
if end_version:
end_version = APIVersion(end_version)
else:
end_version = APIVersion("%s.latest" % start_version.ver_major)
def decor(func):
func.versioned = True
name = utils.get_function_name(func)
versioned_method = VersionedMethod(name, start_version,
end_version, func)
add_substitution(versioned_method)
@functools.wraps(func)
def substitution(obj, *args, **kwargs):
methods = get_substitutions(name, obj.api_version)
if not methods:
raise exceptions.VersionNotFoundForAPIMethod(
obj.api_version.get_string(), name)
method = max(methods, key=lambda f: f.start_version)
return method.func(obj, *args, **kwargs)
if hasattr(func, 'arguments'):
for cli_args, cli_kwargs in func.arguments:
cliutils.add_arg(substitution, *cli_args, **cli_kwargs)
return substitution
return decor