# vim: tabstop=4 shiftwidth=4 softtabstop=4 # Copyright 2011 Nicira Networks, Inc # 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. """ System-level utilities and helper functions. """ import datetime import inspect import logging import os import random import subprocess import socket import sys import ConfigParser import exceptions as exception import flags from exceptions import ProcessExecutionError TIME_FORMAT = "%Y-%m-%dT%H:%M:%SZ" FLAGS = flags.FLAGS def int_from_bool_as_string(subject): """ Interpret a string as a boolean and return either 1 or 0. Any string value in: ('True', 'true', 'On', 'on', '1') is interpreted as a boolean True. Useful for JSON-decoded stuff and config file parsing """ return bool_from_string(subject) and 1 or 0 def bool_from_string(subject): """ Interpret a string as a boolean. Any string value in: ('True', 'true', 'On', 'on', '1') is interpreted as a boolean True. Useful for JSON-decoded stuff and config file parsing """ if type(subject) == type(bool): return subject if hasattr(subject, 'startswith'): # str or unicode... if subject.strip().lower() in ('true', 'on', '1'): return True return False def import_class(import_str): """Returns a class from a string including module and class""" mod_str, _sep, class_str = import_str.rpartition('.') try: #mod_str = os.path.join(FLAGS.state_path, mod_str) __import__(mod_str) return getattr(sys.modules[mod_str], class_str) except (ImportError, ValueError, AttributeError) as e: print e raise exception.NotFound('Class %s cannot be found' % class_str) def import_object(import_str): """Returns an object including a module or module and class""" try: __import__(import_str) return sys.modules[import_str] except ImportError: cls = import_class(import_str) return cls() def fetchfile(url, target): logging.debug("Fetching %s" % url) # c = pycurl.Curl() # fp = open(target, "wb") # c.setopt(c.URL, url) # c.setopt(c.WRITEDATA, fp) # c.perform() # c.close() # fp.close() execute("curl --fail %s -o %s" % (url, target)) def execute(cmd, process_input=None, addl_env=None, check_exit_code=True): logging.debug("Running cmd: %s", cmd) env = os.environ.copy() if addl_env: env.update(addl_env) obj = subprocess.Popen(cmd, shell=True, stdin=subprocess.PIPE, stdout=subprocess.PIPE, stderr=subprocess.PIPE, env=env) result = None if process_input != None: result = obj.communicate(process_input) else: result = obj.communicate() obj.stdin.close() if obj.returncode: logging.debug("Result was %s" % (obj.returncode)) if check_exit_code and obj.returncode != 0: (stdout, stderr) = result raise ProcessExecutionError(exit_code=obj.returncode, stdout=stdout, stderr=stderr, cmd=cmd) return result def abspath(s): return os.path.join(os.path.dirname(__file__), s) # TODO(sirp): when/if utils is extracted to common library, we should remove # the argument's default. #def default_flagfile(filename='nova.conf'): def default_flagfile(filename='quantum.conf'): for arg in sys.argv: if arg.find('flagfile') != -1: break else: if not os.path.isabs(filename): # turn relative filename into an absolute path script_dir = os.path.dirname(inspect.stack()[-1][1]) filename = os.path.abspath(os.path.join(script_dir, filename)) if os.path.exists(filename): sys.argv = \ sys.argv[:1] + ['--flagfile=%s' % filename] + sys.argv[1:] def debug(arg): logging.debug('debug in callback: %s', arg) return arg def runthis(prompt, cmd, check_exit_code=True): logging.debug("Running %s" % (cmd)) exit_code = subprocess.call(cmd.split(" ")) logging.debug(prompt % (exit_code)) if check_exit_code and exit_code != 0: raise ProcessExecutionError(exit_code=exit_code, stdout=None, stderr=None, cmd=cmd) def generate_uid(topic, size=8): return '%s-%s' % (topic, ''.join( [random.choice('01234567890abcdefghijklmnopqrstuvwxyz') for x in xrange(size)])) def generate_mac(): mac = [0x02, 0x16, 0x3e, random.randint(0x00, 0x7f), random.randint(0x00, 0xff), random.randint(0x00, 0xff)] return ':'.join(map(lambda x: "%02x" % x, mac)) def last_octet(address): return int(address.split(".")[-1]) def isotime(at=None): if not at: at = datetime.datetime.utcnow() return at.strftime(TIME_FORMAT) def parse_isotime(timestr): return datetime.datetime.strptime(timestr, TIME_FORMAT) def getPluginFromConfig(file="config.ini"): Config = ConfigParser.ConfigParser() Config.read(file) return Config.get("PLUGIN", "provider") class LazyPluggable(object): """A pluggable backend loaded lazily based on some value.""" def __init__(self, pivot, **backends): self.__backends = backends self.__pivot = pivot self.__backend = None def __get_backend(self): if not self.__backend: backend_name = self.__pivot.value if backend_name not in self.__backends: raise exception.Error('Invalid backend: %s' % backend_name) backend = self.__backends[backend_name] if type(backend) == type(tuple()): name = backend[0] fromlist = backend[1] else: name = backend fromlist = backend self.__backend = __import__(name, None, None, fromlist) logging.info('backend %s', self.__backend) return self.__backend def __getattr__(self, key): backend = self.__get_backend() return getattr(backend, key)