freezer/freezer/utils.py

518 lines
16 KiB
Python

"""
(c) Copyright 2014,2015 Hewlett-Packard Development Company, L.P.
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.
Freezer general utils functions
"""
import datetime
import errno
import logging
import os
import re
import subprocess
import sys
import time
from distutils import spawn as distspawn
from functools import wraps
from six.moves import configparser
class OpenstackOptions:
"""
Stores credentials for OpenStack API.
Can be created using
>> create_from_env()
or
>> create_from_dict(dict)
"""
def __init__(self, user_name, tenant_name, project_name, auth_url,
password, identity_api_version, tenant_id=None,
region_name=None, endpoint_type=None):
self.user_name = user_name
self.tenant_name = tenant_name
self.auth_url = auth_url
self.password = password
self.tenant_id = tenant_id
self.project_name = project_name
self.identity_api_version = identity_api_version
self.region_name = region_name
self.endpoint_type = endpoint_type
if not (self.password and self.user_name and self.auth_url and
(self.tenant_name or self.project_name)):
raise Exception("Please set up in your env:"
"OS_USERNAME, OS_TENANT_NAME/OS_PROJECT_NAME,"
" OS_AUTH_URL, OS_PASSWORD")
@property
def os_options(self):
"""
:return: The OpenStack options which can have tenant_id,
auth_token, service_type, endpoint_type, tenant_name,
object_storage_url, region_name
"""
return {'tenant_id': self.tenant_id,
'tenant_name': self.tenant_name,
'project_name': self.project_name,
'identity_api_version': self.identity_api_version,
'region_name': self.region_name,
'endpoint_type': self.endpoint_type}
@staticmethod
def create_from_env():
return OpenstackOptions.create_from_dict(os.environ)
@staticmethod
def create_from_dict(src_dict):
return OpenstackOptions(
user_name=src_dict.get('OS_USERNAME', None),
tenant_name=src_dict.get('OS_TENANT_NAME', None),
project_name=src_dict.get('OS_PROJECT_NAME', None),
auth_url=src_dict.get('OS_AUTH_URL', None),
identity_api_version=src_dict.get('OS_IDENTITY_API_VERSION',
'2.0'),
password=src_dict.get('OS_PASSWORD', None),
tenant_id=src_dict.get('OS_TENANT_ID', None),
region_name=src_dict.get('OS_REGION_NAME', None),
endpoint_type=src_dict.get('OS_ENDPOINT_TYPE', None)
)
def create_dir_tree(dir):
try:
os.makedirs(dir)
except OSError as exc:
if exc.errno == errno.EEXIST and os.path.isdir(dir):
pass
else:
raise exc
def create_dir(directory, do_log=True):
"""
Creates a directory if it doesn't exists and write the execution
in the logs
"""
expanded_dir_name = os.path.expanduser(directory)
try:
if not os.path.isdir(expanded_dir_name):
if do_log:
logging.warning('[*] Directory {0} does not exists,\
creating...'.format(expanded_dir_name))
os.makedirs(expanded_dir_name)
else:
if do_log:
logging.warning('[*] Directory {0} found!'.format(
expanded_dir_name))
except Exception as error:
err = '[*] Error while creating directory {0}: {1}\
'.format(expanded_dir_name, error)
raise Exception(err)
def save_config_to_file(config, f, section='freezer_default'):
parser = configparser.ConfigParser()
parser.add_section(section)
for option, option_value in config.items():
parser.set(section, option, option_value)
parser.write(f)
f.close()
class DateTime(object):
def __init__(self, value):
if isinstance(value, int):
self.date_time = datetime.datetime.fromtimestamp(value)
elif isinstance(value, datetime.datetime):
self.date_time = value
else:
fmt = '%Y-%m-%dT%H:%M:%S'
try:
self.date_time = datetime.datetime.strptime(value, fmt)
except Exception:
raise Exception('bad datetime format: "{0}'.format(value))
@property
def timestamp(self):
return int(time.mktime(self.date_time.timetuple()))
def __repr__(self):
return self.date_time.strftime('%Y-%m-%d %H:%M:%S')
def __sub__(self, other):
assert isinstance(other, DateTime)
return self.date_time - other.date_time # return timedelta
@staticmethod
def now():
return DateTime(datetime.datetime.now())
def get_vol_fs_type(vol_name):
"""
The argument need to be a full path lvm name i.e. /dev/vg0/var
or a disk partition like /dev/sda1. The returnet value is the
file system type
"""
if os.path.exists(vol_name) is False:
err = '[*] Provided volume name not found: {0} '.format(vol_name)
logging.exception(err)
raise Exception(err)
file_cmd = '{0} -0 -bLs --no-pad --no-buffer --preserve-date \
{1}'.format(find_executable("file"), vol_name)
file_process = subprocess.Popen(
file_cmd, stdin=subprocess.PIPE, stdout=subprocess.PIPE,
stderr=subprocess.PIPE, shell=True,
executable=find_executable("bash"))
(file_out, file_err) = file_process.communicate()
file_match = re.search(r'(\S+?) filesystem data', file_out, re.I)
if file_match is None:
err = '[*] File system type not guessable: {0}'.format(file_err)
logging.exception(err)
raise Exception(err)
else:
filesys_type = file_match.group(1)
logging.info('[*] File system {0} found for volume {1}'.format(
filesys_type, vol_name))
return filesys_type.lower().strip()
def path_join(*args):
"""Should work for windows and linux"""
return "/".join([str(x) for x in args])
def get_mount_from_path(path):
"""
Take a file system path as argument and return the mount point
for that file system path.
:param path: file system path
:returns: mount point of path, rest of the path
"""
if not os.path.exists(path):
logging.critical('[*] Error: provided path does not exist: {0}'
.format(path))
raise IOError
mount_point_path = os.path.abspath(path)
while not os.path.ismount(mount_point_path):
mount_point_path = os.path.dirname(mount_point_path)
return mount_point_path, os.path.relpath(path, mount_point_path)
# see: http://goo.gl/kTQMs
HUMAN_2_SYMBOLS = {
'customary': ('B', 'K', 'M', 'G', 'T', 'P', 'E', 'Z', 'Y'),
'customary_ext': ('byte', 'kilo', 'mega', 'giga', 'tera', 'peta', 'exa',
'zetta', 'iotta'),
'iec': ('Bi', 'Ki', 'Mi', 'Gi', 'Ti', 'Pi', 'Ei', 'Zi', 'Yi'),
'iec_ext': ('byte', 'kibi', 'mebi', 'gibi', 'tebi', 'pebi', 'exbi',
'zebi', 'yobi'),
}
def human2bytes(s):
"""
Attempts to guess the string format based on default symbols
set and return the corresponding bytes as an integer.
When unable to recognize the format ValueError is raised.
"""
if s.isdigit():
return int(s)
if s in (False, None, '-1'):
return -1
init = s
num = ""
while s and s[0:1].isdigit() or s[0:1] == '.':
num += s[0]
s = s[1:]
num = float(num)
letter = s.strip()
for name, sset in HUMAN_2_SYMBOLS.items():
if letter in sset:
break
else:
if letter == 'k':
# treat 'k' as an alias for 'K' as per: http://goo.gl/kTQMs
sset = HUMAN_2_SYMBOLS['customary']
letter = letter.upper()
else:
raise ValueError("can't interpret %r" % init)
prefix = {sset[0]: 1}
for i, s in enumerate(sset[1:]):
prefix[s] = 1 << (i + 1) * 10
return int(num * prefix[letter])
def create_subprocess(cmd):
"""
Create a new subprocess in the OS
:param cmd: command to execute in the subprocess
:return: the output and errors of the subprocess
"""
process = subprocess.Popen(cmd,
stdin=subprocess.PIPE,
stdout=subprocess.PIPE,
stderr=subprocess.PIPE)
return process.communicate()
def date_to_timestamp(date):
fmt = '%Y-%m-%dT%H:%M:%S'
opt_backup_date = datetime.datetime.strptime(date, fmt)
return int(time.mktime(opt_backup_date.timetuple()))
class Bunch:
def __init__(self, **kwds):
self.__dict__.update(kwds)
def __getattr__(self, item):
return self.__dict__.get(item)
class ReSizeStream:
"""
Iterator/File-like object for changing size of chunk in stream
"""
def __init__(self, stream, length, chunk_size):
self.stream = stream
self.length = length
self.chunk_size = chunk_size
self.reminder = ""
self.transmitted = 0
def __len__(self):
return self.length
def __iter__(self):
return self
def next(self):
logging.info("Transmitted {0} of {1}".format(self.transmitted,
self.length))
chunk_size = self.chunk_size
if len(self.reminder) > chunk_size:
result = self.reminder[:chunk_size]
self.reminder = self.reminder[chunk_size:]
self.transmitted += len(result)
return result
else:
stop = False
while not stop and len(self.reminder) < chunk_size:
try:
self.reminder += next(self.stream)
except StopIteration:
stop = True
if stop:
result = self.reminder
if len(self.reminder) == 0:
raise StopIteration()
self.reminder = []
self.transmitted += len(result)
return result
else:
result = self.reminder[:chunk_size]
self.reminder = self.reminder[chunk_size:]
self.transmitted += len(result)
return result
def read(self, chunk_size):
self.chunk_size = chunk_size
return self.next()
def dequote(s):
"""
If a string has single or double quotes around it, remove them.
Make sure the pair of quotes match.
If a matching pair of quotes is not found, return the string unchanged.
"""
s = s.rstrip('\n')
if (s[0] == s[-1]) and s.startswith(("'", '"')):
return s[1:-1]
return s
def find_executable(name):
return distspawn.find_executable(name)
def openssl_path():
from freezer import winutils
if winutils.is_windows():
return 'openssl'
else:
return find_executable('openssl')
def tar_path():
"""This function returns tar binary path"""
from freezer import winutils
if winutils.is_windows():
path_to_binaries = os.path.dirname(os.path.abspath(__file__))
return '{0}\\bin\\tar.exe'.format(path_to_binaries)
tar = (get_executable_path('gnutar') or get_executable_path('gtar')
or get_executable_path('tar'))
if not tar:
raise Exception('Please install gnu tar (gtar) as it is a '
'mandatory requirement to use freezer.')
return tar
def get_executable_path(binary):
"""
This function returns the executable path of a given binary
if it is found in the system.
:param binary:
:type binary: str
:rtype: str
:return: Absoulte Path to the executable file
"""
from freezer import winutils
if winutils.is_windows():
path_to_binaries = os.path.dirname(os.path.abspath(__file__))
return '{0}\\bin\\{1}.exe'.format(path_to_binaries, binary)
elif is_bsd():
return (distspawn.find_executable(binary) or
distspawn.find_executable(binary, path=':'.join(sys.path)))
else:
return distspawn.find_executable(binary)
def alter_proxy(proxy):
"""
Read proxy option from dictionary and alter the HTTP_PROXY and/or
HTTPS_PROXY system variables
"""
# Default case where 'proxy' key is not set -- do nothing
proxy_value = proxy.lower()
# python-swift client takes into account both
# upper and lower case proxies so clear them all
os.environ.pop("http_proxy", None)
os.environ.pop("https_proxy", None)
os.environ.pop("HTTP_PROXY", None)
os.environ.pop("HTTPS_PROXY", None)
if proxy_value.startswith('http://') or \
proxy_value.startswith('https://'):
logging.info('[*] Using proxy {0}'.format(proxy_value))
os.environ['HTTP_PROXY'] = str(proxy_value)
os.environ['HTTPS_PROXY'] = str(proxy_value)
else:
raise Exception('Proxy has unknown scheme')
def is_bsd():
return 'darwin' in sys.platform or 'bsd' in sys.platform
def shield(func):
"""Remove try except boilerplate code from functions"""
@wraps(func)
def wrapper(*args, **kwargs):
try:
return func(*args, **kwargs)
except Exception as error:
logging.error(error)
return wrapper
def delete_file(path_to_file):
"""Delete a file from the file system
"""
try:
os.remove(path_to_file)
except Exception:
logging.warning("Error deleting file {0}".format(path_to_file))
class Namespace(dict):
"""A dict subclass that exposes its items as attributes.
Warning: Namespace instances do not have direct access to the
dict methods.
"""
def __init__(self, obj={}):
super(Namespace, self).__init__(obj)
def __dir__(self):
return tuple(self)
def __repr__(self):
return "%s(%s)" % (type(self).__name__,
super(Namespace, self).__repr__())
def __getattribute__(self, name):
try:
return self[name]
except KeyError:
# Return None in case the value doesn't exists
# this is not an issue for the apiclient because it skips
# None values
return None
def __setattr__(self, name, value):
self[name] = value
def __delattr__(self, name):
del self[name]
@classmethod
def from_object(cls, obj, names=None):
if names is None:
names = dir(obj)
ns = {name:getattr(obj, name) for name in names}
return cls(ns)
@classmethod
def from_mapping(cls, ns, names=None):
if names:
ns = {name: ns[name] for name in names}
return cls(ns)
@classmethod
def from_sequence(cls, seq, names=None):
if names:
seq = {name: val for name, val in seq if name in names}
return cls(seq)
@staticmethod
def hasattr(ns, name):
try:
object.__getattribute__(ns, name)
except AttributeError:
return False
return True
@staticmethod
def getattr(ns, name):
return object.__getattribute__(ns, name)
@staticmethod
def setattr(ns, name, value):
return object.__setattr__(ns, name, value)
@staticmethod
def delattr(ns, name):
return object.__delattr__(ns, name)