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OpenStack Study: utils.py**** CubicPower OpenStack Study ****
# Copyright 2010 United States Government as represented by the # Administrator of the National Aeronautics and Space Administration. # Copyright 2011 Justin Santa Barbara # All Rights Reserved. # # 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. """Utilities and helper functions.""" import contextlib import datetime import functools import hashlib import inspect import multiprocessing import os import pyclbr import random import re import shutil import socket import struct import sys import tempfile from xml.sax import saxutils import eventlet import netaddr from oslo.config import cfg from oslo import messaging import six from nova import exception from nova.openstack.common import excutils from nova.openstack.common import gettextutils from nova.openstack.common.gettextutils import _ from nova.openstack.common import importutils from nova.openstack.common import lockutils from nova.openstack.common import log as logging from nova.openstack.common import processutils from nova.openstack.common import timeutils notify_decorator = 'nova.notifications.notify_decorator' monkey_patch_opts = [ cfg.BoolOpt('monkey_patch', default=False, help='Whether to log monkey patching'), cfg.ListOpt('monkey_patch_modules', default=[ 'nova.api.ec2.cloud:%s' % (notify_decorator), 'nova.compute.api:%s' % (notify_decorator) ], help='List of modules/decorators to monkey patch'), ] utils_opts = [ cfg.IntOpt('password_length', default=12, help='Length of generated instance admin passwords'), cfg.StrOpt('instance_usage_audit_period', default='month', help='Time period to generate instance usages for. ' 'Time period must be hour, day, month or year'), cfg.StrOpt('rootwrap_config', default="/etc/nova/rootwrap.conf", help='Path to the rootwrap configuration file to use for ' 'running commands as root'), cfg.StrOpt('tempdir', help='Explicitly specify the temporary working directory'), ] CONF = cfg.CONF CONF.register_opts(monkey_patch_opts) CONF.register_opts(utils_opts) CONF.import_opt('network_api_class', 'nova.network') LOG = logging.getLogger(__name__) # used in limits TIME_UNITS = { 'SECOND': 1, 'MINUTE': 60, 'HOUR': 3600, 'DAY': 84400 } _IS_NEUTRON = None synchronized = lockutils.synchronized_with_prefix('nova-') SM_IMAGE_PROP_PREFIX = "image_" SM_INHERITABLE_KEYS = ( 'min_ram', 'min_disk', 'disk_format', 'container_format', )
**** CubicPower OpenStack Study **** def vpn_ping(address, port, timeout=0.05, session_id=None): """Sends a vpn negotiation packet and returns the server session. Returns False on a failure. Basic packet structure is below. Client packet (14 bytes):: 0 1 8 9 13 +-+--------+-----+ |x| cli_id |?????| +-+--------+-----+ x = packet identifier 0x38 cli_id = 64 bit identifier ? = unknown, probably flags/padding Server packet (26 bytes):: 0 1 8 9 13 14 21 2225 +-+--------+-----+--------+----+ |x| srv_id |?????| cli_id |????| +-+--------+-----+--------+----+ x = packet identifier 0x40 cli_id = 64 bit identifier ? = unknown, probably flags/padding bit 9 was 1 and the rest were 0 in testing """ if session_id is None: session_id = random.randint(0, 0xffffffffffffffff) sock = socket.socket(socket.AF_INET, socket.SOCK_DGRAM) data = struct.pack('!BQxxxxx', 0x38, session_id) sock.sendto(data, (address, port)) sock.settimeout(timeout) try: received = sock.recv(2048) except socket.timeout: return False finally: sock.close() fmt = '!BQxxxxxQxxxx' if len(received) != struct.calcsize(fmt): LOG.warn(_('Expected to receive %(exp)s bytes, but actually %(act)s') % dict(exp=struct.calcsize(fmt), act=len(received))) return False (identifier, server_sess, client_sess) = struct.unpack(fmt, received) if identifier == 0x40 and client_sess == session_id: return server_sess
**** CubicPower OpenStack Study **** def _get_root_helper(): return 'sudo nova-rootwrap %s' % CONF.rootwrap_config
**** CubicPower OpenStack Study **** def execute(*cmd, **kwargs): """Convenience wrapper around oslo's execute() method.""" if 'run_as_root' in kwargs and not 'root_helper' in kwargs: kwargs['root_helper'] = _get_root_helper() return processutils.execute(*cmd, **kwargs)
**** CubicPower OpenStack Study **** def trycmd(*args, **kwargs): """Convenience wrapper around oslo's trycmd() method.""" if 'run_as_root' in kwargs and not 'root_helper' in kwargs: kwargs['root_helper'] = _get_root_helper() return processutils.trycmd(*args, **kwargs)
**** CubicPower OpenStack Study **** def novadir(): import nova return os.path.abspath(nova.__file__).split('nova/__init__.py')[0]
**** CubicPower OpenStack Study **** def generate_uid(topic, size=8): characters = '01234567890abcdefghijklmnopqrstuvwxyz' choices = [random.choice(characters) for _x in xrange(size)] return '%s-%s' % (topic, ''.join(choices)) # Default symbols to use for passwords. Avoids visually confusing characters. # ~6 bits per symbol DEFAULT_PASSWORD_SYMBOLS = ('23456789', # Removed: 0,1 'ABCDEFGHJKLMNPQRSTUVWXYZ', # Removed: I, O 'abcdefghijkmnopqrstuvwxyz') # Removed: l # ~5 bits per symbol EASIER_PASSWORD_SYMBOLS = ('23456789', # Removed: 0, 1 'ABCDEFGHJKLMNPQRSTUVWXYZ') # Removed: I, O
**** CubicPower OpenStack Study **** def last_completed_audit_period(unit=None, before=None): """This method gives you the most recently *completed* audit period. arguments: units: string, one of 'hour', 'day', 'month', 'year' Periods normally begin at the beginning (UTC) of the period unit (So a 'day' period begins at midnight UTC, a 'month' unit on the 1st, a 'year' on Jan, 1) unit string may be appended with an optional offset like so: 'day@18' This will begin the period at 18:00 UTC. 'month@15' starts a monthly period on the 15th, and year@3 begins a yearly one on March 1st. before: Give the audit period most recently completed before returns: 2 tuple of datetimes (begin, end) The begin timestamp of this audit period is the same as the end of the previous. """ if not unit: unit = CONF.instance_usage_audit_period offset = 0 if '@' in unit: unit, offset = unit.split("@", 1) offset = int(offset) if before is not None: rightnow = before else: rightnow = timeutils.utcnow() if unit not in ('month', 'day', 'year', 'hour'): raise ValueError('Time period must be hour, day, month or year') if unit == 'month': if offset == 0: offset = 1 end = datetime.datetime(day=offset, month=rightnow.month, year=rightnow.year) if end >= rightnow: year = rightnow.year if 1 >= rightnow.month: year -= 1 month = 12 + (rightnow.month - 1) else: month = rightnow.month - 1 end = datetime.datetime(day=offset, month=month, year=year) year = end.year if 1 >= end.month: year -= 1 month = 12 + (end.month - 1) else: month = end.month - 1 begin = datetime.datetime(day=offset, month=month, year=year) elif unit == 'year': if offset == 0: offset = 1 end = datetime.datetime(day=1, month=offset, year=rightnow.year) if end >= rightnow: end = datetime.datetime(day=1, month=offset, year=rightnow.year - 1) begin = datetime.datetime(day=1, month=offset, year=rightnow.year - 2) else: begin = datetime.datetime(day=1, month=offset, year=rightnow.year - 1) elif unit == 'day': end = datetime.datetime(hour=offset, day=rightnow.day, month=rightnow.month, year=rightnow.year) if end >= rightnow: end = end - datetime.timedelta(days=1) begin = end - datetime.timedelta(days=1) elif unit == 'hour': end = rightnow.replace(minute=offset, second=0, microsecond=0) if end >= rightnow: end = end - datetime.timedelta(hours=1) begin = end - datetime.timedelta(hours=1) return (begin, end)
**** CubicPower OpenStack Study **** def generate_password(length=None, symbolgroups=DEFAULT_PASSWORD_SYMBOLS): """Generate a random password from the supplied symbol groups. At least one symbol from each group will be included. Unpredictable results if length is less than the number of symbol groups. Believed to be reasonably secure (with a reasonable password length!) """ if length is None: length = CONF.password_length r = random.SystemRandom() # NOTE(jerdfelt): Some password policies require at least one character # from each group of symbols, so start off with one random character # from each symbol group password = [r.choice(s) for s in symbolgroups] # If length < len(symbolgroups), the leading characters will only # be from the first length groups. Try our best to not be predictable # by shuffling and then truncating. r.shuffle(password) password = password[:length] length -= len(password) # then fill with random characters from all symbol groups symbols = ''.join(symbolgroups) password.extend([r.choice(symbols) for _i in xrange(length)]) # finally shuffle to ensure first x characters aren't from a # predictable group r.shuffle(password) return ''.join(password)
**** CubicPower OpenStack Study **** def get_my_ipv4_address(): """Run ip route/addr commands to figure out the best ipv4 """ LOCALHOST = '127.0.0.1' try: out = execute('ip', '-f', 'inet', '-o', 'route', 'show') # Find the default route regex_default = ('default\s*via\s*' '(\d{1,3}\.\d{1,3}\.\d{1,3}\.\d{1,3})' '\s*dev\s*(\w*)\s*') default_routes = re.findall(regex_default, out[0]) if not default_routes: return LOCALHOST gateway, iface = default_routes[0] # Find the right subnet for the gateway/interface for # the default route route = ('(\d{1,3}\.\d{1,3}\.\d{1,3}\.\d{1,3})\/(\d{1,2})' '\s*dev\s*(\w*)\s*') for match in re.finditer(route, out[0]): subnet = netaddr.IPNetwork(match.group(1) + "/" + match.group(2)) if (match.group(3) == iface and netaddr.IPAddress(gateway) in subnet): try: return _get_ipv4_address_for_interface(iface) except exception.NovaException: pass except Exception as ex: LOG.error(_("Couldn't get IPv4 : %(ex)s") % {'ex': ex}) return LOCALHOST
**** CubicPower OpenStack Study **** def _get_ipv4_address_for_interface(iface): """Run ip addr show for an interface and grab its ipv4 addresses """ try: out = execute('ip', '-f', 'inet', '-o', 'addr', 'show', iface) regexp_address = re.compile('inet\s*' '(\d{1,3}\.\d{1,3}\.\d{1,3}\.\d{1,3})') address = [m.group(1) for m in regexp_address.finditer(out[0]) if m.group(1) != '127.0.0.1'] if address: return address[0] else: msg = _('IPv4 address is not found.: %s') % out[0] raise exception.NovaException(msg) except Exception as ex: msg = _("Couldn't get IPv4 of %(interface)s" " : %(ex)s") % {'interface': iface, 'ex': ex} LOG.error(msg) raise exception.NovaException(msg)
**** CubicPower OpenStack Study **** def get_my_linklocal(interface): try: if_str = execute('ip', '-f', 'inet6', '-o', 'addr', 'show', interface) condition = '\s+inet6\s+([0-9a-f:]+)/\d+\s+scope\s+link' links = [re.search(condition, x) for x in if_str[0].split('\n')] address = [w.group(1) for w in links if w is not None] if address[0] is not None: return address[0] else: msg = _('Link Local address is not found.:%s') % if_str raise exception.NovaException(msg) except Exception as ex: msg = _("Couldn't get Link Local IP of %(interface)s" " :%(ex)s") % {'interface': interface, 'ex': ex} raise exception.NovaException(msg)
**** CubicPower OpenStack Study **** class LazyPluggable(object): """A pluggable backend loaded lazily based on some value."""
**** CubicPower OpenStack Study **** def __init__(self, pivot, config_group=None, **backends): self.__backends = backends self.__pivot = pivot self.__backend = None self.__config_group = config_group
**** CubicPower OpenStack Study **** def __get_backend(self): if not self.__backend: if self.__config_group is None: backend_name = CONF[self.__pivot] else: backend_name = CONF[self.__config_group][self.__pivot] if backend_name not in self.__backends: msg = _('Invalid backend: %s') % backend_name raise exception.NovaException(msg) backend = self.__backends[backend_name] if isinstance(backend, tuple): name = backend[0] fromlist = backend[1] else: name = backend fromlist = backend self.__backend = __import__(name, None, None, fromlist) return self.__backend
**** CubicPower OpenStack Study **** def __getattr__(self, key): backend = self.__get_backend() return getattr(backend, key) def xhtml_escape(value): """Escapes a string so it is valid within XML or XHTML. """ return saxutils.escape(value, {'"': '"', "'": '''}) def utf8(value): """Try to turn a string into utf-8 if possible. Code is directly from the utf8 function in http://github.com/facebook/tornado/blob/master/tornado/escape.py """ if isinstance(value, unicode): return value.encode('utf-8') elif isinstance(value, gettextutils.Message): return unicode(value).encode('utf-8') assert isinstance(value, str) return value def check_isinstance(obj, cls): """Checks that obj is of type cls, and lets PyLint infer types.""" if isinstance(obj, cls): return obj raise Exception(_('Expected object of type: %s') % (str(cls))) def parse_server_string(server_str): """Parses the given server_string and returns a list of host and port. If it's not a combination of host part and port, the port element is a null string. If the input is invalid expression, return a null list. """ try: # First of all, exclude pure IPv6 address (w/o port). if netaddr.valid_ipv6(server_str): return (server_str, '') # Next, check if this is IPv6 address with a port number combination. if server_str.find("]:") != -1: (address, port) = server_str.replace('[', '', 1).split(']:') return (address, port) # Third, check if this is a combination of an address and a port if server_str.find(':') == -1: return (server_str, '') # This must be a combination of an address and a port (address, port) = server_str.split(':') return (address, port) except Exception: LOG.error(_('Invalid server_string: %s'), server_str) return ('', '') def is_int_like(val): """Check if a value looks like an int.""" try: return str(int(val)) == str(val) except Exception: return False def is_valid_ipv4(address): """Verify that address represents a valid IPv4 address.""" try: return netaddr.valid_ipv4(address) except Exception: return False def is_valid_ipv6(address): try: return netaddr.valid_ipv6(address) except Exception: return False def is_valid_ip_address(address): return is_valid_ipv4(address) or is_valid_ipv6(address) def is_valid_ipv6_cidr(address): try: str(netaddr.IPNetwork(address, version=6).cidr) return True except Exception: return False def get_shortened_ipv6(address): addr = netaddr.IPAddress(address, version=6) return str(addr.ipv6()) def get_shortened_ipv6_cidr(address): net = netaddr.IPNetwork(address, version=6) return str(net.cidr) def is_valid_cidr(address): """Check if address is valid The provided address can be a IPv6 or a IPv4 CIDR address. """ try: # Validate the correct CIDR Address netaddr.IPNetwork(address) except netaddr.core.AddrFormatError: return False except UnboundLocalError: # NOTE(MotoKen): work around bug in netaddr 0.7.5 (see detail in # https://github.com/drkjam/netaddr/issues/2) return False # Prior validation partially verify /xx part # Verify it here ip_segment = address.split('/') if (len(ip_segment) <= 1 or ip_segment[1] == ''): return False return True def get_ip_version(network): """Returns the IP version of a network (IPv4 or IPv6). Raises AddrFormatError if invalid network. """ if netaddr.IPNetwork(network).version == 6: return "IPv6" elif netaddr.IPNetwork(network).version == 4: return "IPv4" def monkey_patch(): """If the CONF.monkey_patch set as True, this function patches a decorator for all functions in specified modules. You can set decorators for each modules using CONF.monkey_patch_modules. The format is "Module path:Decorator function". Example: 'nova.api.ec2.cloud:nova.notifications.notify_decorator' Parameters of the decorator is as follows. (See nova.notifications.notify_decorator) name - name of the function function - object of the function """ # If CONF.monkey_patch is not True, this function do nothing. if not CONF.monkey_patch: return # Get list of modules and decorators for module_and_decorator in CONF.monkey_patch_modules: module, decorator_name = module_and_decorator.split(':') # import decorator function decorator = importutils.import_class(decorator_name) __import__(module) # Retrieve module information using pyclbr module_data = pyclbr.readmodule_ex(module) for key in module_data.keys(): # set the decorator for the class methods if isinstance(module_data[key], pyclbr.Class): clz = importutils.import_class("%s.%s" % (module, key)) for method, func in inspect.getmembers(clz, inspect.ismethod): setattr(clz, method, decorator("%s.%s.%s" % (module, key, method), func)) # set the decorator for the function if isinstance(module_data[key], pyclbr.Function): func = importutils.import_class("%s.%s" % (module, key)) setattr(sys.modules[module], key, decorator("%s.%s" % (module, key), func)) def convert_to_list_dict(lst, label): """Convert a value or list into a list of dicts.""" if not lst: return None if not isinstance(lst, list): lst = [lst] return [{label: x} for x in lst] def make_dev_path(dev, partition=None, base='/dev'): """Return a path to a particular device. >>> make_dev_path('xvdc') /dev/xvdc >>> make_dev_path('xvdc', 1) /dev/xvdc1 """ path = os.path.join(base, dev) if partition: path += str(partition) return path def sanitize_hostname(hostname): """Return a hostname which conforms to RFC-952 and RFC-1123 specs.""" if isinstance(hostname, unicode): hostname = hostname.encode('latin-1', 'ignore') hostname = re.sub('[ _]', '-', hostname) hostname = re.sub('[^\w.-]+', '', hostname) hostname = hostname.lower() hostname = hostname.strip('.-') return hostname def read_cached_file(filename, cache_info, reload_func=None): """Read from a file if it has been modified. :param cache_info: dictionary to hold opaque cache. :param reload_func: optional function to be called with data when file is reloaded due to a modification. :returns: data from file """ mtime = os.path.getmtime(filename) if not cache_info or mtime != cache_info.get('mtime'): LOG.debug(_("Reloading cached file %s") % filename) with open(filename) as fap: cache_info['data'] = fap.read() cache_info['mtime'] = mtime if reload_func: reload_func(cache_info['data']) return cache_info['data'] @contextlib.contextmanager def temporary_mutation(obj, **kwargs): """Temporarily set the attr on a particular object to a given value then revert when finished. One use of this is to temporarily set the read_deleted flag on a context object: with temporary_mutation(context, read_deleted="yes"): do_something_that_needed_deleted_objects() """
**** CubicPower OpenStack Study **** def xhtml_escape(value): """Escapes a string so it is valid within XML or XHTML. """ return saxutils.escape(value, {'"': '"', "'": '''})
**** CubicPower OpenStack Study **** def utf8(value): """Try to turn a string into utf-8 if possible. Code is directly from the utf8 function in http://github.com/facebook/tornado/blob/master/tornado/escape.py """ if isinstance(value, unicode): return value.encode('utf-8') elif isinstance(value, gettextutils.Message): return unicode(value).encode('utf-8') assert isinstance(value, str) return value
**** CubicPower OpenStack Study **** def check_isinstance(obj, cls): """Checks that obj is of type cls, and lets PyLint infer types.""" if isinstance(obj, cls): return obj raise Exception(_('Expected object of type: %s') % (str(cls)))
**** CubicPower OpenStack Study **** def parse_server_string(server_str): """Parses the given server_string and returns a list of host and port. If it's not a combination of host part and port, the port element is a null string. If the input is invalid expression, return a null list. """ try: # First of all, exclude pure IPv6 address (w/o port). if netaddr.valid_ipv6(server_str): return (server_str, '') # Next, check if this is IPv6 address with a port number combination. if server_str.find("]:") != -1: (address, port) = server_str.replace('[', '', 1).split(']:') return (address, port) # Third, check if this is a combination of an address and a port if server_str.find(':') == -1: return (server_str, '') # This must be a combination of an address and a port (address, port) = server_str.split(':') return (address, port) except Exception: LOG.error(_('Invalid server_string: %s'), server_str) return ('', '')
**** CubicPower OpenStack Study **** def is_int_like(val): """Check if a value looks like an int.""" try: return str(int(val)) == str(val) except Exception: return False
**** CubicPower OpenStack Study **** def is_valid_ipv4(address): """Verify that address represents a valid IPv4 address.""" try: return netaddr.valid_ipv4(address) except Exception: return False
**** CubicPower OpenStack Study **** def is_valid_ipv6(address): try: return netaddr.valid_ipv6(address) except Exception: return False
**** CubicPower OpenStack Study **** def is_valid_ip_address(address): return is_valid_ipv4(address) or is_valid_ipv6(address)
**** CubicPower OpenStack Study **** def is_valid_ipv6_cidr(address): try: str(netaddr.IPNetwork(address, version=6).cidr) return True except Exception: return False
**** CubicPower OpenStack Study **** def get_shortened_ipv6(address): addr = netaddr.IPAddress(address, version=6) return str(addr.ipv6())
**** CubicPower OpenStack Study **** def get_shortened_ipv6_cidr(address): net = netaddr.IPNetwork(address, version=6) return str(net.cidr)
**** CubicPower OpenStack Study **** def is_valid_cidr(address): """Check if address is valid The provided address can be a IPv6 or a IPv4 CIDR address. """ try: # Validate the correct CIDR Address netaddr.IPNetwork(address) except netaddr.core.AddrFormatError: return False except UnboundLocalError: # NOTE(MotoKen): work around bug in netaddr 0.7.5 (see detail in # https://github.com/drkjam/netaddr/issues/2) return False # Prior validation partially verify /xx part # Verify it here ip_segment = address.split('/') if (len(ip_segment) <= 1 or ip_segment[1] == ''): return False return True
**** CubicPower OpenStack Study **** def get_ip_version(network): """Returns the IP version of a network (IPv4 or IPv6). Raises AddrFormatError if invalid network. """ if netaddr.IPNetwork(network).version == 6: return "IPv6" elif netaddr.IPNetwork(network).version == 4: return "IPv4"
**** CubicPower OpenStack Study **** def monkey_patch(): """If the CONF.monkey_patch set as True, this function patches a decorator for all functions in specified modules. You can set decorators for each modules using CONF.monkey_patch_modules. The format is "Module path:Decorator function". Example: 'nova.api.ec2.cloud:nova.notifications.notify_decorator' Parameters of the decorator is as follows. (See nova.notifications.notify_decorator) name - name of the function function - object of the function """ # If CONF.monkey_patch is not True, this function do nothing. if not CONF.monkey_patch: return # Get list of modules and decorators for module_and_decorator in CONF.monkey_patch_modules: module, decorator_name = module_and_decorator.split(':') # import decorator function decorator = importutils.import_class(decorator_name) __import__(module) # Retrieve module information using pyclbr module_data = pyclbr.readmodule_ex(module) for key in module_data.keys(): # set the decorator for the class methods if isinstance(module_data[key], pyclbr.Class): clz = importutils.import_class("%s.%s" % (module, key)) for method, func in inspect.getmembers(clz, inspect.ismethod): setattr(clz, method, decorator("%s.%s.%s" % (module, key, method), func)) # set the decorator for the function if isinstance(module_data[key], pyclbr.Function): func = importutils.import_class("%s.%s" % (module, key)) setattr(sys.modules[module], key, decorator("%s.%s" % (module, key), func))
**** CubicPower OpenStack Study **** def convert_to_list_dict(lst, label): """Convert a value or list into a list of dicts.""" if not lst: return None if not isinstance(lst, list): lst = [lst] return [{label: x} for x in lst]
**** CubicPower OpenStack Study **** def make_dev_path(dev, partition=None, base='/dev'): """Return a path to a particular device. >>> make_dev_path('xvdc') /dev/xvdc >>> make_dev_path('xvdc', 1) /dev/xvdc1 """ path = os.path.join(base, dev) if partition: path += str(partition) return path
**** CubicPower OpenStack Study **** def sanitize_hostname(hostname): """Return a hostname which conforms to RFC-952 and RFC-1123 specs.""" if isinstance(hostname, unicode): hostname = hostname.encode('latin-1', 'ignore') hostname = re.sub('[ _]', '-', hostname) hostname = re.sub('[^\w.-]+', '', hostname) hostname = hostname.lower() hostname = hostname.strip('.-') return hostname
**** CubicPower OpenStack Study **** def read_cached_file(filename, cache_info, reload_func=None): """Read from a file if it has been modified. :param cache_info: dictionary to hold opaque cache. :param reload_func: optional function to be called with data when file is reloaded due to a modification. :returns: data from file """ mtime = os.path.getmtime(filename) if not cache_info or mtime != cache_info.get('mtime'): LOG.debug(_("Reloading cached file %s") % filename) with open(filename) as fap: cache_info['data'] = fap.read() cache_info['mtime'] = mtime if reload_func: reload_func(cache_info['data']) return cache_info['data'] @contextlib.contextmanager
**** CubicPower OpenStack Study **** def temporary_mutation(obj, **kwargs): """Temporarily set the attr on a particular object to a given value then revert when finished. One use of this is to temporarily set the read_deleted flag on a context object: with temporary_mutation(context, read_deleted="yes"): do_something_that_needed_deleted_objects() """
**** CubicPower OpenStack Study **** def is_dict_like(thing): return hasattr(thing, 'has_key')
**** CubicPower OpenStack Study **** def get(thing, attr, default): if is_dict_like(thing): return thing.get(attr, default) else: return getattr(thing, attr, default)
**** CubicPower OpenStack Study **** def set_value(thing, attr, val): if is_dict_like(thing): thing[attr] = val else: setattr(thing, attr, val)
**** CubicPower OpenStack Study **** def delete(thing, attr): if is_dict_like(thing): del thing[attr] else: delattr(thing, attr) NOT_PRESENT = object() old_values = {} for attr, new_value in kwargs.items(): old_values[attr] = get(obj, attr, NOT_PRESENT) set_value(obj, attr, new_value) try: yield finally: for attr, old_value in old_values.items(): if old_value is NOT_PRESENT: delete(obj, attr) else: set_value(obj, attr, old_value) def generate_mac_address(): """Generate an Ethernet MAC address.""" # NOTE(vish): We would prefer to use 0xfe here to ensure that linux # bridge mac addresses don't change, but it appears to # conflict with libvirt, so we use the next highest octet # that has the unicast and locally administered bits set # properly: 0xfa. # Discussion: https://bugs.launchpad.net/nova/+bug/921838 mac = [0xfa, 0x16, 0x3e, random.randint(0x00, 0xff), random.randint(0x00, 0xff), random.randint(0x00, 0xff)] return ':'.join(map(lambda x: "%02x" % x, mac)) def read_file_as_root(file_path): """Secure helper to read file as root.""" try: out, _err = execute('cat', file_path, run_as_root=True) return out except processutils.ProcessExecutionError: raise exception.FileNotFound(file_path=file_path) @contextlib.contextmanager def temporary_chown(path, owner_uid=None): """Temporarily chown a path. :param owner_uid: UID of temporary owner (defaults to current user) """ if owner_uid is None: owner_uid = os.getuid() orig_uid = os.stat(path).st_uid if orig_uid != owner_uid: execute('chown', owner_uid, path, run_as_root=True) try: yield finally: if orig_uid != owner_uid: execute('chown', orig_uid, path, run_as_root=True) def chown(path, owner_uid=None): """chown a path. :param owner_uid: UID of owner (defaults to current user) """ if owner_uid is None: owner_uid = os.getuid() orig_uid = os.stat(path).st_uid if orig_uid != owner_uid: execute('chown', owner_uid, path, run_as_root=True) @contextlib.contextmanager def tempdir(**kwargs): argdict = kwargs.copy() if 'dir' not in argdict: argdict['dir'] = CONF.tempdir tmpdir = tempfile.mkdtemp(**argdict) try: yield tmpdir finally: try: shutil.rmtree(tmpdir) except OSError as e: LOG.error(_('Could not remove tmpdir: %s'), str(e)) def walk_class_hierarchy(clazz, encountered=None): """Walk class hierarchy, yielding most derived classes first.""" if not encountered: encountered = [] for subclass in clazz.__subclasses__(): if subclass not in encountered: encountered.append(subclass) # drill down to leaves first for subsubclass in walk_class_hierarchy(subclass, encountered): yield subsubclass yield subclass
**** CubicPower OpenStack Study **** def generate_mac_address(): """Generate an Ethernet MAC address.""" # NOTE(vish): We would prefer to use 0xfe here to ensure that linux # bridge mac addresses don't change, but it appears to # conflict with libvirt, so we use the next highest octet # that has the unicast and locally administered bits set # properly: 0xfa. # Discussion: https://bugs.launchpad.net/nova/+bug/921838 mac = [0xfa, 0x16, 0x3e, random.randint(0x00, 0xff), random.randint(0x00, 0xff), random.randint(0x00, 0xff)] return ':'.join(map(lambda x: "%02x" % x, mac))
**** CubicPower OpenStack Study **** def read_file_as_root(file_path): """Secure helper to read file as root.""" try: out, _err = execute('cat', file_path, run_as_root=True) return out except processutils.ProcessExecutionError: raise exception.FileNotFound(file_path=file_path) @contextlib.contextmanager
**** CubicPower OpenStack Study **** def temporary_chown(path, owner_uid=None): """Temporarily chown a path. :param owner_uid: UID of temporary owner (defaults to current user) """ if owner_uid is None: owner_uid = os.getuid() orig_uid = os.stat(path).st_uid if orig_uid != owner_uid: execute('chown', owner_uid, path, run_as_root=True) try: yield finally: if orig_uid != owner_uid: execute('chown', orig_uid, path, run_as_root=True)
**** CubicPower OpenStack Study **** def chown(path, owner_uid=None): """chown a path. :param owner_uid: UID of owner (defaults to current user) """ if owner_uid is None: owner_uid = os.getuid() orig_uid = os.stat(path).st_uid if orig_uid != owner_uid: execute('chown', owner_uid, path, run_as_root=True) @contextlib.contextmanager
**** CubicPower OpenStack Study **** def tempdir(**kwargs): argdict = kwargs.copy() if 'dir' not in argdict: argdict['dir'] = CONF.tempdir tmpdir = tempfile.mkdtemp(**argdict) try: yield tmpdir finally: try: shutil.rmtree(tmpdir) except OSError as e: LOG.error(_('Could not remove tmpdir: %s'), str(e))
**** CubicPower OpenStack Study **** def walk_class_hierarchy(clazz, encountered=None): """Walk class hierarchy, yielding most derived classes first.""" if not encountered: encountered = [] for subclass in clazz.__subclasses__(): if subclass not in encountered: encountered.append(subclass) # drill down to leaves first for subsubclass in walk_class_hierarchy(subclass, encountered): yield subsubclass yield subclass
**** CubicPower OpenStack Study **** class UndoManager(object): """Provides a mechanism to facilitate rolling back a series of actions when an exception is raised. """
**** CubicPower OpenStack Study **** def __init__(self): self.undo_stack = []
**** CubicPower OpenStack Study **** def undo_with(self, undo_func): self.undo_stack.append(undo_func)
**** CubicPower OpenStack Study **** def _rollback(self): for undo_func in reversed(self.undo_stack): undo_func()
**** CubicPower OpenStack Study **** def rollback_and_reraise(self, msg=None, **kwargs): """Rollback a series of actions then re-raise the exception. .. note:: (sirp) This should only be called within an exception handler. """ with excutils.save_and_reraise_exception(): if msg: LOG.exception(msg, **kwargs) self._rollback() def mkfs(fs, path, label=None, run_as_root=False): """Format a file or block device :param fs: Filesystem type (examples include 'swap', 'ext3', 'ext4' 'btrfs', etc.) :param path: Path to file or block device to format :param label: Volume label to use """ if fs == 'swap': args = ['mkswap'] else: args = ['mkfs', '-t', fs] #add -F to force no interactive execute on non-block device. if fs in ('ext3', 'ext4', 'ntfs'): args.extend(['-F']) if label: if fs in ('msdos', 'vfat'): label_opt = '-n' else: label_opt = '-L' args.extend([label_opt, label]) args.append(path) execute(*args, run_as_root=run_as_root) def last_bytes(file_like_object, num): """Return num bytes from the end of the file, and remaining byte count. :param file_like_object: The file to read :param num: The number of bytes to return :returns (data, remaining) """ try: file_like_object.seek(-num, os.SEEK_END) except IOError as e: if e.errno == 22: file_like_object.seek(0, os.SEEK_SET) else: raise remaining = file_like_object.tell() return (file_like_object.read(), remaining) def metadata_to_dict(metadata): result = {} for item in metadata: if not item.get('deleted'): result[item['key']] = item['value'] return result def dict_to_metadata(metadata): result = [] for key, value in metadata.iteritems(): result.append(dict(key=key, value=value)) return result def instance_meta(instance): if isinstance(instance['metadata'], dict): return instance['metadata'] else: return metadata_to_dict(instance['metadata']) def instance_sys_meta(instance): if not instance.get('system_metadata'): return {} if isinstance(instance['system_metadata'], dict): return instance['system_metadata'] else: return metadata_to_dict(instance['system_metadata']) def get_wrapped_function(function): """Get the method at the bottom of a stack of decorators.""" if not hasattr(function, 'func_closure') or not function.func_closure: return function
**** CubicPower OpenStack Study **** def mkfs(fs, path, label=None, run_as_root=False): """Format a file or block device :param fs: Filesystem type (examples include 'swap', 'ext3', 'ext4' 'btrfs', etc.) :param path: Path to file or block device to format :param label: Volume label to use """ if fs == 'swap': args = ['mkswap'] else: args = ['mkfs', '-t', fs] #add -F to force no interactive execute on non-block device. if fs in ('ext3', 'ext4', 'ntfs'): args.extend(['-F']) if label: if fs in ('msdos', 'vfat'): label_opt = '-n' else: label_opt = '-L' args.extend([label_opt, label]) args.append(path) execute(*args, run_as_root=run_as_root)
**** CubicPower OpenStack Study **** def last_bytes(file_like_object, num): """Return num bytes from the end of the file, and remaining byte count. :param file_like_object: The file to read :param num: The number of bytes to return :returns (data, remaining) """ try: file_like_object.seek(-num, os.SEEK_END) except IOError as e: if e.errno == 22: file_like_object.seek(0, os.SEEK_SET) else: raise remaining = file_like_object.tell() return (file_like_object.read(), remaining)
**** CubicPower OpenStack Study **** def metadata_to_dict(metadata): result = {} for item in metadata: if not item.get('deleted'): result[item['key']] = item['value'] return result
**** CubicPower OpenStack Study **** def dict_to_metadata(metadata): result = [] for key, value in metadata.iteritems(): result.append(dict(key=key, value=value)) return result
**** CubicPower OpenStack Study **** def instance_meta(instance): if isinstance(instance['metadata'], dict): return instance['metadata'] else: return metadata_to_dict(instance['metadata'])
**** CubicPower OpenStack Study **** def instance_sys_meta(instance): if not instance.get('system_metadata'): return {} if isinstance(instance['system_metadata'], dict): return instance['system_metadata'] else: return metadata_to_dict(instance['system_metadata'])
**** CubicPower OpenStack Study **** def get_wrapped_function(function): """Get the method at the bottom of a stack of decorators.""" if not hasattr(function, 'func_closure') or not function.func_closure: return function
**** CubicPower OpenStack Study **** def _get_wrapped_function(function): if not hasattr(function, 'func_closure') or not function.func_closure: return None for closure in function.func_closure: func = closure.cell_contents deeper_func = _get_wrapped_function(func) if deeper_func: return deeper_func elif hasattr(closure.cell_contents, '__call__'): return closure.cell_contents return _get_wrapped_function(function) def expects_func_args(*args):
**** CubicPower OpenStack Study **** def expects_func_args(*args):
**** CubicPower OpenStack Study **** def _decorator_checker(dec): @functools.wraps(dec) def _decorator(f): base_f = get_wrapped_function(f) arg_names, a, kw, _default = inspect.getargspec(base_f) if a or kw or set(args) <= set(arg_names): # NOTE (ndipanov): We can't really tell if correct stuff will # be passed if it's a function with *args or **kwargs so # we still carry on and hope for the best return dec(f) else: raise TypeError("Decorated function %(f_name)s does not " "have the arguments expected by the " "decorator %(d_name)s" % {'f_name': base_f.__name__, 'd_name': dec.__name__}) return _decorator return _decorator_checker
**** CubicPower OpenStack Study **** def _decorator(f): base_f = get_wrapped_function(f) arg_names, a, kw, _default = inspect.getargspec(base_f) if a or kw or set(args) <= set(arg_names): # NOTE (ndipanov): We can't really tell if correct stuff will # be passed if it's a function with *args or **kwargs so # we still carry on and hope for the best return dec(f) else: raise TypeError("Decorated function %(f_name)s does not " "have the arguments expected by the " "decorator %(d_name)s" % {'f_name': base_f.__name__, 'd_name': dec.__name__}) return _decorator return _decorator_checker
**** CubicPower OpenStack Study **** class ExceptionHelper(object): """Class to wrap another and translate the ClientExceptions raised by its function calls to the actual ones. """
**** CubicPower OpenStack Study **** def __init__(self, target): self._target = target
**** CubicPower OpenStack Study **** def __getattr__(self, name): func = getattr(self._target, name) @functools.wraps(func) def wrapper(*args, **kwargs): try: return func(*args, **kwargs) except messaging.ExpectedException as e: raise (e.exc_info[1], None, e.exc_info[2]) return wrapper def check_string_length(value, name, min_length=0, max_length=None): """Check the length of specified string :param value: the value of the string :param name: the name of the string :param min_length: the min_length of the string :param max_length: the max_length of the string """ if not isinstance(value, six.string_types): msg = _("%s is not a string or unicode") % name raise exception.InvalidInput(message=msg) if len(value) < min_length: msg = _("%(name)s has a minimum character requirement of " "%(min_length)s.") % {'name': name, 'min_length': min_length} raise exception.InvalidInput(message=msg) if max_length and len(value) > max_length: msg = _("%(name)s has more than %(max_length)s " "characters.") % {'name': name, 'max_length': max_length} raise exception.InvalidInput(message=msg) def validate_integer(value, name, min_value=None, max_value=None): """Make sure that value is a valid integer, potentially within range.""" try: value = int(str(value)) except (ValueError, UnicodeEncodeError): msg = _('%(value_name)s must be an integer') raise exception.InvalidInput(reason=( msg % {'value_name': name})) if min_value is not None: if value < min_value: msg = _('%(value_name)s must be >= %(min_value)d') raise exception.InvalidInput( reason=(msg % {'value_name': name, 'min_value': min_value})) if max_value is not None: if value > max_value: msg = _('%(value_name)s must be <= %(max_value)d') raise exception.InvalidInput( reason=( msg % {'value_name': name, 'max_value': max_value}) ) return value def spawn_n(func, *args, **kwargs): """Passthrough method for eventlet.spawn_n. This utility exists so that it can be stubbed for testing without interfering with the service spawns. """ eventlet.spawn_n(func, *args, **kwargs) def is_none_string(val): """Check if a string represents a None value. """ if not isinstance(val, six.string_types): return False return val.lower() == 'none' def convert_version_to_int(version): try: if isinstance(version, six.string_types): version = convert_version_to_tuple(version) if isinstance(version, tuple): return reduce(lambda x, y: (x * 1000) + y, version) except Exception: raise exception.NovaException(message="Hypervisor version invalid.") def convert_version_to_str(version_int): version_numbers = [] factor = 1000 while version_int != 0: version_number = version_int - (version_int // factor * factor) version_numbers.insert(0, str(version_number)) version_int = version_int / factor return reduce(lambda x, y: "%s.%s" % (x, y), version_numbers) def convert_version_to_tuple(version_str): return tuple(int(part) for part in version_str.split('.')) def is_neutron(): global _IS_NEUTRON if _IS_NEUTRON is not None: return _IS_NEUTRON try: # compatibility with Folsom/Grizzly configs cls_name = CONF.network_api_class if cls_name == 'nova.network.quantumv2.api.API': cls_name = 'nova.network.neutronv2.api.API' from nova.network.neutronv2 import api as neutron_api _IS_NEUTRON = issubclass(importutils.import_class(cls_name), neutron_api.API) except ImportError: _IS_NEUTRON = False return _IS_NEUTRON def reset_is_neutron(): global _IS_NEUTRON _IS_NEUTRON = None def is_auto_disk_config_disabled(auto_disk_config_raw): auto_disk_config_disabled = False if auto_disk_config_raw is not None: adc_lowered = auto_disk_config_raw.strip().lower() if adc_lowered == "disabled": auto_disk_config_disabled = True return auto_disk_config_disabled def get_auto_disk_config_from_instance(instance=None, sys_meta=None): if sys_meta is None: sys_meta = instance_sys_meta(instance) return sys_meta.get("image_auto_disk_config") def get_auto_disk_config_from_image_props(image_properties): return image_properties.get("auto_disk_config") def get_system_metadata_from_image(image_meta, flavor=None): system_meta = {} prefix_format = SM_IMAGE_PROP_PREFIX + '%s' for key, value in image_meta.get('properties', {}).iteritems(): new_value = unicode(value)[:255] system_meta[prefix_format % key] = new_value for key in SM_INHERITABLE_KEYS: value = image_meta.get(key) if key == 'min_disk' and flavor: if image_meta.get('disk_format') == 'vhd': value = flavor['root_gb'] else: value = max(value, flavor['root_gb']) if value is None: continue system_meta[prefix_format % key] = value return system_meta def get_image_from_system_metadata(system_meta): image_meta = {} properties = {} if not isinstance(system_meta, dict): system_meta = metadata_to_dict(system_meta) for key, value in system_meta.iteritems(): if value is None: continue # NOTE(xqueralt): Not sure this has to inherit all the properties or # just the ones we need. Leaving it for now to keep the old behaviour. if key.startswith(SM_IMAGE_PROP_PREFIX): key = key[len(SM_IMAGE_PROP_PREFIX):] if key in SM_INHERITABLE_KEYS: image_meta[key] = value else: # Skip properties that are non-inheritable if key in CONF.non_inheritable_image_properties: continue properties[key] = value if properties: image_meta['properties'] = properties return image_meta def get_hash_str(base_str): """returns string that represents hash of base_str (in hex format).""" return hashlib.md5(base_str).hexdigest() def cpu_count(): try: return multiprocessing.cpu_count() except NotImplementedError: return 1
**** CubicPower OpenStack Study **** def wrapper(*args, **kwargs): try: return func(*args, **kwargs) except messaging.ExpectedException as e: raise (e.exc_info[1], None, e.exc_info[2]) return wrapper def check_string_length(value, name, min_length=0, max_length=None): """Check the length of specified string :param value: the value of the string :param name: the name of the string :param min_length: the min_length of the string :param max_length: the max_length of the string """ if not isinstance(value, six.string_types): msg = _("%s is not a string or unicode") % name raise exception.InvalidInput(message=msg) if len(value) < min_length: msg = _("%(name)s has a minimum character requirement of " "%(min_length)s.") % {'name': name, 'min_length': min_length} raise exception.InvalidInput(message=msg) if max_length and len(value) > max_length: msg = _("%(name)s has more than %(max_length)s " "characters.") % {'name': name, 'max_length': max_length} raise exception.InvalidInput(message=msg) def validate_integer(value, name, min_value=None, max_value=None): """Make sure that value is a valid integer, potentially within range.""" try: value = int(str(value)) except (ValueError, UnicodeEncodeError): msg = _('%(value_name)s must be an integer') raise exception.InvalidInput(reason=( msg % {'value_name': name})) if min_value is not None: if value < min_value: msg = _('%(value_name)s must be >= %(min_value)d') raise exception.InvalidInput( reason=(msg % {'value_name': name, 'min_value': min_value})) if max_value is not None: if value > max_value: msg = _('%(value_name)s must be <= %(max_value)d') raise exception.InvalidInput( reason=( msg % {'value_name': name, 'max_value': max_value}) ) return value def spawn_n(func, *args, **kwargs): """Passthrough method for eventlet.spawn_n. This utility exists so that it can be stubbed for testing without interfering with the service spawns. """ eventlet.spawn_n(func, *args, **kwargs) def is_none_string(val): """Check if a string represents a None value. """ if not isinstance(val, six.string_types): return False return val.lower() == 'none' def convert_version_to_int(version): try: if isinstance(version, six.string_types): version = convert_version_to_tuple(version) if isinstance(version, tuple): return reduce(lambda x, y: (x * 1000) + y, version) except Exception: raise exception.NovaException(message="Hypervisor version invalid.") def convert_version_to_str(version_int): version_numbers = [] factor = 1000 while version_int != 0: version_number = version_int - (version_int // factor * factor) version_numbers.insert(0, str(version_number)) version_int = version_int / factor return reduce(lambda x, y: "%s.%s" % (x, y), version_numbers) def convert_version_to_tuple(version_str): return tuple(int(part) for part in version_str.split('.')) def is_neutron(): global _IS_NEUTRON if _IS_NEUTRON is not None: return _IS_NEUTRON try: # compatibility with Folsom/Grizzly configs cls_name = CONF.network_api_class if cls_name == 'nova.network.quantumv2.api.API': cls_name = 'nova.network.neutronv2.api.API' from nova.network.neutronv2 import api as neutron_api _IS_NEUTRON = issubclass(importutils.import_class(cls_name), neutron_api.API) except ImportError: _IS_NEUTRON = False return _IS_NEUTRON def reset_is_neutron(): global _IS_NEUTRON _IS_NEUTRON = None def is_auto_disk_config_disabled(auto_disk_config_raw): auto_disk_config_disabled = False if auto_disk_config_raw is not None: adc_lowered = auto_disk_config_raw.strip().lower() if adc_lowered == "disabled": auto_disk_config_disabled = True return auto_disk_config_disabled def get_auto_disk_config_from_instance(instance=None, sys_meta=None): if sys_meta is None: sys_meta = instance_sys_meta(instance) return sys_meta.get("image_auto_disk_config") def get_auto_disk_config_from_image_props(image_properties): return image_properties.get("auto_disk_config") def get_system_metadata_from_image(image_meta, flavor=None): system_meta = {} prefix_format = SM_IMAGE_PROP_PREFIX + '%s' for key, value in image_meta.get('properties', {}).iteritems(): new_value = unicode(value)[:255] system_meta[prefix_format % key] = new_value for key in SM_INHERITABLE_KEYS: value = image_meta.get(key) if key == 'min_disk' and flavor: if image_meta.get('disk_format') == 'vhd': value = flavor['root_gb'] else: value = max(value, flavor['root_gb']) if value is None: continue system_meta[prefix_format % key] = value return system_meta def get_image_from_system_metadata(system_meta): image_meta = {} properties = {} if not isinstance(system_meta, dict): system_meta = metadata_to_dict(system_meta) for key, value in system_meta.iteritems(): if value is None: continue # NOTE(xqueralt): Not sure this has to inherit all the properties or # just the ones we need. Leaving it for now to keep the old behaviour. if key.startswith(SM_IMAGE_PROP_PREFIX): key = key[len(SM_IMAGE_PROP_PREFIX):] if key in SM_INHERITABLE_KEYS: image_meta[key] = value else: # Skip properties that are non-inheritable if key in CONF.non_inheritable_image_properties: continue properties[key] = value if properties: image_meta['properties'] = properties return image_meta def get_hash_str(base_str): """returns string that represents hash of base_str (in hex format).""" return hashlib.md5(base_str).hexdigest() def cpu_count(): try: return multiprocessing.cpu_count() except NotImplementedError: return 1
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