##// END OF EJS Templates
release: Finish preparation for 4.18.0
release: Finish preparation for 4.18.0

File last commit:

r4141:72477738 default
r4182:f37a3126 v4.18.0 stable
Show More
1100 lines | 31.1 KiB | text/x-python | PythonLexer
# -*- coding: utf-8 -*-
# Copyright (C) 2011-2019 RhodeCode GmbH
# This program is free software: you can redistribute it and/or modify
# it under the terms of the GNU Affero General Public License, version 3
# (only), as published by the Free Software Foundation.
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# GNU General Public License for more details.
# You should have received a copy of the GNU Affero General Public License
# along with this program. If not, see <http://www.gnu.org/licenses/>.
# This program is dual-licensed. If you wish to learn more about the
# RhodeCode Enterprise Edition, including its added features, Support services,
# and proprietary license terms, please see https://rhodecode.com/licenses/
Some simple helper functions
import collections
import datetime
import dateutil.relativedelta
import hashlib
import logging
import re
import sys
import time
import urllib
import urlobject
import uuid
import getpass
from functools import update_wrapper, partial
import pygments.lexers
import sqlalchemy
import sqlalchemy.engine.url
import sqlalchemy.exc
import sqlalchemy.sql
import webob
import pyramid.threadlocal
from pyramid import compat
from pyramid.settings import asbool
import rhodecode
from rhodecode.translation import _, _pluralize
def md5(s):
return hashlib.md5(s).hexdigest()
def md5_safe(s):
return md5(safe_str(s))
def sha1(s):
return hashlib.sha1(s).hexdigest()
def sha1_safe(s):
return sha1(safe_str(s))
def __get_lem(extra_mapping=None):
Get language extension map based on what's inside pygments lexers
d = collections.defaultdict(lambda: [])
def __clean(s):
s = s.lstrip('*')
s = s.lstrip('.')
if s.find('[') != -1:
exts = []
start, stop = s.find('['), s.find(']')
for suffix in s[start + 1:stop]:
exts.append(s[:s.find('[')] + suffix)
return [e.lower() for e in exts]
return [s.lower()]
for lx, t in sorted(pygments.lexers.LEXERS.items()):
m = map(__clean, t[-2])
if m:
m = reduce(lambda x, y: x + y, m)
for ext in m:
desc = lx.replace('Lexer', '')
data = dict(d)
extra_mapping = extra_mapping or {}
if extra_mapping:
for k, v in extra_mapping.items():
if k not in data:
# register new mapping2lexer
data[k] = [v]
return data
def str2bool(_str):
returns True/False value from given string, it tries to translate the
string into boolean
:param _str: string value to translate into boolean
:rtype: boolean
:returns: boolean from given string
if _str is None:
return False
if _str in (True, False):
return _str
_str = str(_str).strip().lower()
return _str in ('t', 'true', 'y', 'yes', 'on', '1')
def aslist(obj, sep=None, strip=True):
Returns given string separated by sep as list
:param obj:
:param sep:
:param strip:
if isinstance(obj, (basestring,)):
lst = obj.split(sep)
if strip:
lst = [v.strip() for v in lst]
return lst
elif isinstance(obj, (list, tuple)):
return obj
elif obj is None:
return []
return [obj]
def convert_line_endings(line, mode):
Converts a given line "line end" accordingly to given mode
Available modes are::
0 - Unix
1 - Mac
2 - DOS
:param line: given line to convert
:param mode: mode to convert to
:rtype: str
:return: converted line according to mode
if mode == 0:
line = line.replace('\r\n', '\n')
line = line.replace('\r', '\n')
elif mode == 1:
line = line.replace('\r\n', '\r')
line = line.replace('\n', '\r')
elif mode == 2:
line = re.sub('\r(?!\n)|(?<!\r)\n', '\r\n', line)
return line
def detect_mode(line, default):
Detects line break for given line, if line break couldn't be found
given default value is returned
:param line: str line
:param default: default
:rtype: int
:return: value of line end on of 0 - Unix, 1 - Mac, 2 - DOS
if line.endswith('\r\n'):
return 2
elif line.endswith('\n'):
return 0
elif line.endswith('\r'):
return 1
return default
def safe_int(val, default=None):
Returns int() of val if val is not convertable to int use default
:param val:
:param default:
val = int(val)
except (ValueError, TypeError):
val = default
return val
def safe_unicode(str_, from_encoding=None, use_chardet=False):
safe unicode function. Does few trick to turn str_ into unicode
In case of UnicodeDecode error, we try to return it with encoding detected
by chardet library if it fails fallback to unicode with errors replaced
:param str_: string to decode
:rtype: unicode
:returns: unicode object
if isinstance(str_, unicode):
return str_
if not from_encoding:
DEFAULT_ENCODINGS = aslist(rhodecode.CONFIG.get('default_encoding',
'utf8'), sep=',')
from_encoding = DEFAULT_ENCODINGS
if not isinstance(from_encoding, (list, tuple)):
from_encoding = [from_encoding]
return unicode(str_)
except UnicodeDecodeError:
for enc in from_encoding:
return unicode(str_, enc)
except UnicodeDecodeError:
if use_chardet:
import chardet
encoding = chardet.detect(str_)['encoding']
if encoding is None:
raise Exception()
return str_.decode(encoding)
except (ImportError, UnicodeDecodeError, Exception):
return unicode(str_, from_encoding[0], 'replace')
return unicode(str_, from_encoding[0], 'replace')
def safe_str(unicode_, to_encoding=None, use_chardet=False):
safe str function. Does few trick to turn unicode_ into string
In case of UnicodeEncodeError, we try to return it with encoding detected
by chardet library if it fails fallback to string with errors replaced
:param unicode_: unicode to encode
:rtype: str
:returns: str object
# if it's not basestr cast to str
if not isinstance(unicode_, compat.string_types):
return str(unicode_)
if isinstance(unicode_, str):
return unicode_
if not to_encoding:
DEFAULT_ENCODINGS = aslist(rhodecode.CONFIG.get('default_encoding',
'utf8'), sep=',')
if not isinstance(to_encoding, (list, tuple)):
to_encoding = [to_encoding]
for enc in to_encoding:
return unicode_.encode(enc)
except UnicodeEncodeError:
if use_chardet:
import chardet
encoding = chardet.detect(unicode_)['encoding']
if encoding is None:
raise UnicodeEncodeError()
return unicode_.encode(encoding)
except (ImportError, UnicodeEncodeError):
return unicode_.encode(to_encoding[0], 'replace')
return unicode_.encode(to_encoding[0], 'replace')
def remove_suffix(s, suffix):
if s.endswith(suffix):
s = s[:-1 * len(suffix)]
return s
def remove_prefix(s, prefix):
if s.startswith(prefix):
s = s[len(prefix):]
return s
def find_calling_context(ignore_modules=None):
Look through the calling stack and return the frame which called
this function and is part of core module ( ie. rhodecode.* )
:param ignore_modules: list of modules to ignore eg. ['rhodecode.lib']
ignore_modules = ignore_modules or []
f = sys._getframe(2)
while f.f_back is not None:
name = f.f_globals.get('__name__')
if name and name.startswith(__name__.split('.')[0]):
if name not in ignore_modules:
return f
f = f.f_back
return None
def ping_connection(connection, branch):
if branch:
# "branch" refers to a sub-connection of a connection,
# we don't want to bother pinging on these.
# turn off "close with result". This flag is only used with
# "connectionless" execution, otherwise will be False in any case
save_should_close_with_result = connection.should_close_with_result
connection.should_close_with_result = False
# run a SELECT 1. use a core select() so that
# the SELECT of a scalar value without a table is
# appropriately formatted for the backend
except sqlalchemy.exc.DBAPIError as err:
# catch SQLAlchemy's DBAPIError, which is a wrapper
# for the DBAPI's exception. It includes a .connection_invalidated
# attribute which specifies if this connection is a "disconnect"
# condition, which is based on inspection of the original exception
# by the dialect in use.
if err.connection_invalidated:
# run the same SELECT again - the connection will re-validate
# itself and establish a new connection. The disconnect detection
# here also causes the whole connection pool to be invalidated
# so that all stale connections are discarded.
# restore "close with result"
connection.should_close_with_result = save_should_close_with_result
def engine_from_config(configuration, prefix='sqlalchemy.', **kwargs):
"""Custom engine_from_config functions."""
log = logging.getLogger('sqlalchemy.engine')
use_ping_connection = asbool(configuration.pop('sqlalchemy.db1.ping_connection', None))
debug = asbool(configuration.pop('sqlalchemy.db1.debug_query', None))
engine = sqlalchemy.engine_from_config(configuration, prefix, **kwargs)
def color_sql(sql):
color_seq = '\033[1;33m' # This is yellow: code 33
normal = '\x1b[0m'
return ''.join([color_seq, sql, normal])
if use_ping_connection:
log.debug('Adding ping_connection on the engine config.')
sqlalchemy.event.listen(engine, "engine_connect", ping_connection)
if debug:
# attach events only for debug configuration
def before_cursor_execute(conn, cursor, statement,
parameters, context, executemany):
setattr(conn, 'query_start_time', time.time())
log.info(color_sql(">>>>> STARTING QUERY >>>>>"))
calling_context = find_calling_context(ignore_modules=[
if calling_context:
log.info(color_sql('call context %s:%s' % (
def after_cursor_execute(conn, cursor, statement,
parameters, context, executemany):
delattr(conn, 'query_start_time')
sqlalchemy.event.listen(engine, "before_cursor_execute", before_cursor_execute)
sqlalchemy.event.listen(engine, "after_cursor_execute", after_cursor_execute)
return engine
def get_encryption_key(config):
secret = config.get('rhodecode.encrypted_values.secret')
default = config['beaker.session.secret']
return secret or default
def age(prevdate, now=None, show_short_version=False, show_suffix=True,
Turns a datetime into an age string.
If show_short_version is True, this generates a shorter string with
an approximate age; ex. '1 day ago', rather than '1 day and 23 hours ago'.
Code of this function is written in special way so it's easier to
backport it to javascript. If you mean to update it, please also update
`jquery.timeago-extension.js` file
:param prevdate: datetime object
:param now: get current time, if not define we use
:param show_short_version: if it should approximate the date and
return a shorter string
:param show_suffix:
:param short_format: show short format, eg 2D instead of 2 days
:rtype: unicode
:returns: unicode words describing age
def _get_relative_delta(now, prevdate):
base = dateutil.relativedelta.relativedelta(now, prevdate)
return {
'year': base.years,
'month': base.months,
'day': base.days,
'hour': base.hours,
'minute': base.minutes,
'second': base.seconds,
def _is_leap_year(year):
return year % 4 == 0 and (year % 100 != 0 or year % 400 == 0)
def get_month(prevdate):
return prevdate.month
def get_year(prevdate):
return prevdate.year
now = now or datetime.datetime.now()
order = ['year', 'month', 'day', 'hour', 'minute', 'second']
deltas = {}
future = False
if prevdate > now:
now_old = now
now = prevdate
prevdate = now_old
future = True
if future:
prevdate = prevdate.replace(microsecond=0)
# Get date parts deltas
for part in order:
rel_delta = _get_relative_delta(now, prevdate)
deltas[part] = rel_delta[part]
# Fix negative offsets (there is 1 second between 10:59:59 and 11:00:00,
# not 1 hour, -59 minutes and -59 seconds)
offsets = [[5, 60], [4, 60], [3, 24]]
for element in offsets: # seconds, minutes, hours
num = element[0]
length = element[1]
part = order[num]
carry_part = order[num - 1]
if deltas[part] < 0:
deltas[part] += length
deltas[carry_part] -= 1
# Same thing for days except that the increment depends on the (variable)
# number of days in the month
month_lengths = [31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31]
if deltas['day'] < 0:
if get_month(prevdate) == 2 and _is_leap_year(get_year(prevdate)):
deltas['day'] += 29
deltas['day'] += month_lengths[get_month(prevdate) - 1]
deltas['month'] -= 1
if deltas['month'] < 0:
deltas['month'] += 12
deltas['year'] -= 1
# Format the result
if short_format:
fmt_funcs = {
'year': lambda d: u'%dy' % d,
'month': lambda d: u'%dm' % d,
'day': lambda d: u'%dd' % d,
'hour': lambda d: u'%dh' % d,
'minute': lambda d: u'%dmin' % d,
'second': lambda d: u'%dsec' % d,
fmt_funcs = {
'year': lambda d: _pluralize(u'${num} year', u'${num} years', d, mapping={'num': d}).interpolate(),
'month': lambda d: _pluralize(u'${num} month', u'${num} months', d, mapping={'num': d}).interpolate(),
'day': lambda d: _pluralize(u'${num} day', u'${num} days', d, mapping={'num': d}).interpolate(),
'hour': lambda d: _pluralize(u'${num} hour', u'${num} hours', d, mapping={'num': d}).interpolate(),
'minute': lambda d: _pluralize(u'${num} minute', u'${num} minutes', d, mapping={'num': d}).interpolate(),
'second': lambda d: _pluralize(u'${num} second', u'${num} seconds', d, mapping={'num': d}).interpolate(),
i = 0
for part in order:
value = deltas[part]
if value != 0:
if i < 5:
sub_part = order[i + 1]
sub_value = deltas[sub_part]
sub_value = 0
if sub_value == 0 or show_short_version:
_val = fmt_funcs[part](value)
if future:
if show_suffix:
return _(u'in ${ago}', mapping={'ago': _val})
return _(_val)
if show_suffix:
return _(u'${ago} ago', mapping={'ago': _val})
return _(_val)
val = fmt_funcs[part](value)
val_detail = fmt_funcs[sub_part](sub_value)
mapping = {'val': val, 'detail': val_detail}
if short_format:
datetime_tmpl = _(u'${val}, ${detail}', mapping=mapping)
if show_suffix:
datetime_tmpl = _(u'${val}, ${detail} ago', mapping=mapping)
if future:
datetime_tmpl = _(u'in ${val}, ${detail}', mapping=mapping)
datetime_tmpl = _(u'${val} and ${detail}', mapping=mapping)
if show_suffix:
datetime_tmpl = _(u'${val} and ${detail} ago', mapping=mapping)
if future:
datetime_tmpl = _(u'in ${val} and ${detail}', mapping=mapping)
return datetime_tmpl
i += 1
return _(u'just now')
def age_from_seconds(seconds):
seconds = safe_int(seconds) or 0
prevdate = time_to_datetime(time.time() + seconds)
return age(prevdate, show_suffix=False, show_short_version=True)
def cleaned_uri(uri):
Quotes '[' and ']' from uri if there is only one of them.
according to RFC3986 we cannot use such chars in uri
:param uri:
:return: uri without this chars
return urllib.quote(uri, safe='@$:/')
def uri_filter(uri):
Removes user:password from given url string
:param uri:
:rtype: unicode
:returns: filtered list of strings
if not uri:
return ''
proto = ''
for pat in ('https://', 'http://'):
if uri.startswith(pat):
uri = uri[len(pat):]
proto = pat
# remove passwords and username
uri = uri[uri.find('@') + 1:]
# get the port
cred_pos = uri.find(':')
if cred_pos == -1:
host, port = uri, None
host, port = uri[:cred_pos], uri[cred_pos + 1:]
return filter(None, [proto, host, port])
def credentials_filter(uri):
Returns a url with removed credentials
:param uri:
uri = uri_filter(uri)
# check if we have port
if len(uri) > 2 and uri[2]:
uri[2] = ':' + uri[2]
return ''.join(uri)
def get_host_info(request):
Generate host info, to obtain full url e.g https://server.com
use this
if not request:
return {}
qualified_home_url = request.route_url('home')
parsed_url = urlobject.URLObject(qualified_home_url)
decoded_path = safe_unicode(urllib.unquote(parsed_url.path.rstrip('/')))
return {
'scheme': parsed_url.scheme,
'netloc': parsed_url.netloc+decoded_path,
'hostname': parsed_url.hostname,
def get_clone_url(request, uri_tmpl, repo_name, repo_id, repo_type, **override):
qualified_home_url = request.route_url('home')
parsed_url = urlobject.URLObject(qualified_home_url)
decoded_path = safe_unicode(urllib.unquote(parsed_url.path.rstrip('/')))
args = {
'scheme': parsed_url.scheme,
'user': '',
'sys_user': getpass.getuser(),
# path if we use proxy-prefix
'netloc': parsed_url.netloc+decoded_path,
'hostname': parsed_url.hostname,
'prefix': decoded_path,
'repo': repo_name,
'repoid': str(repo_id),
'repo_type': repo_type
args['user'] = urllib.quote(safe_str(args['user']))
for k, v in args.items():
uri_tmpl = uri_tmpl.replace('{%s}' % k, v)
# special case for SVN clone url
if repo_type == 'svn':
uri_tmpl = uri_tmpl.replace('ssh://', 'svn+ssh://')
# remove leading @ sign if it's present. Case of empty user
url_obj = urlobject.URLObject(uri_tmpl)
url = url_obj.with_netloc(url_obj.netloc.lstrip('@'))
return safe_unicode(url)
def get_commit_safe(repo, commit_id=None, commit_idx=None, pre_load=None):
Safe version of get_commit if this commit doesn't exists for a
repository it returns a Dummy one instead
:param repo: repository instance
:param commit_id: commit id as str
:param pre_load: optional list of commit attributes to load
# TODO(skreft): remove these circular imports
from rhodecode.lib.vcs.backends.base import BaseRepository, EmptyCommit
from rhodecode.lib.vcs.exceptions import RepositoryError
if not isinstance(repo, BaseRepository):
raise Exception('You must pass an Repository '
'object as first argument got %s', type(repo))
commit = repo.get_commit(
commit_id=commit_id, commit_idx=commit_idx, pre_load=pre_load)
except (RepositoryError, LookupError):
commit = EmptyCommit()
return commit
def datetime_to_time(dt):
if dt:
return time.mktime(dt.timetuple())
def time_to_datetime(tm):
if tm:
if isinstance(tm, compat.string_types):
tm = float(tm)
except ValueError:
return datetime.datetime.fromtimestamp(tm)
def time_to_utcdatetime(tm):
if tm:
if isinstance(tm, compat.string_types):
tm = float(tm)
except ValueError:
return datetime.datetime.utcfromtimestamp(tm)
MENTIONS_REGEX = re.compile(
# ^@ or @ without any special chars in front
# main body starts with letter, then can be . - _
def extract_mentioned_users(s):
Returns unique usernames from given string s that have @mention
:param s: string to get mentions
usrs = set()
for username in MENTIONS_REGEX.findall(s):
return sorted(list(usrs), key=lambda k: k.lower())
class AttributeDictBase(dict):
def __getstate__(self):
odict = self.__dict__ # get attribute dictionary
return odict
def __setstate__(self, dict):
self.__dict__ = dict
__setattr__ = dict.__setitem__
__delattr__ = dict.__delitem__
class StrictAttributeDict(AttributeDictBase):
Strict Version of Attribute dict which raises an Attribute error when
requested attribute is not set
def __getattr__(self, attr):
return self[attr]
except KeyError:
raise AttributeError('%s object has no attribute %s' % (
self.__class__, attr))
class AttributeDict(AttributeDictBase):
def __getattr__(self, attr):
return self.get(attr, None)
class OrderedDefaultDict(collections.OrderedDict, collections.defaultdict):
def __init__(self, default_factory=None, *args, **kwargs):
# in python3 you can omit the args to super
super(OrderedDefaultDict, self).__init__(*args, **kwargs)
self.default_factory = default_factory
def fix_PATH(os_=None):
Get current active python path, and append it to PATH variable to fix
issues of subprocess calls and different python versions
if os_ is None:
import os
os = os_
cur_path = os.path.split(sys.executable)[0]
if not os.environ['PATH'].startswith(cur_path):
os.environ['PATH'] = '%s:%s' % (cur_path, os.environ['PATH'])
def obfuscate_url_pw(engine):
_url = engine or ''
_url = sqlalchemy.engine.url.make_url(engine)
if _url.password:
_url.password = 'XXXXX'
except Exception:
return unicode(_url)
def get_server_url(environ):
req = webob.Request(environ)
return req.host_url + req.script_name
def unique_id(hexlen=32):
alphabet = "23456789ABCDEFGHJKLMNPQRSTUVWXYZabcdefghjklmnpqrstuvwxyz"
return suuid(truncate_to=hexlen, alphabet=alphabet)
def suuid(url=None, truncate_to=22, alphabet=None):
Generate and return a short URL safe UUID.
If the url parameter is provided, set the namespace to the provided
URL and generate a UUID.
:param url to get the uuid for
:truncate_to: truncate the basic 22 UUID to shorter version
The IDs won't be universally unique any longer, but the probability of
a collision will still be very low.
# Define our alphabet.
# If no URL is given, generate a random UUID.
if url is None:
unique_id = uuid.uuid4().int
unique_id = uuid.uuid3(uuid.NAMESPACE_URL, url).int
alphabet_length = len(_ALPHABET)
output = []
while unique_id > 0:
digit = unique_id % alphabet_length
unique_id = int(unique_id / alphabet_length)
return "".join(output)[:truncate_to]
def get_current_rhodecode_user(request=None):
Gets rhodecode user from request
pyramid_request = request or pyramid.threadlocal.get_current_request()
# web case
if pyramid_request and hasattr(pyramid_request, 'user'):
return pyramid_request.user
# api case
if pyramid_request and hasattr(pyramid_request, 'rpc_user'):
return pyramid_request.rpc_user
return None
def action_logger_generic(action, namespace=''):
A generic logger for actions useful to the system overview, tries to find
an acting user for the context of the call otherwise reports unknown user
:param action: logging message eg 'comment 5 deleted'
:param type: string
:param namespace: namespace of the logging message eg. 'repo.comments'
:param type: string
logger_name = 'rhodecode.actions'
if namespace:
logger_name += '.' + namespace
log = logging.getLogger(logger_name)
# get a user if we can
user = get_current_rhodecode_user()
logfunc = log.info
if not user:
user = '<unknown user>'
logfunc = log.warning
logfunc('Logging action by {}: {}'.format(user, action))
def escape_split(text, sep=',', maxsplit=-1):
Allows for escaping of the separator: e.g. arg='foo\, bar'
It should be noted that the way bash et. al. do command line parsing, those
single quotes are required.
escaped_sep = r'\%s' % sep
if escaped_sep not in text:
return text.split(sep, maxsplit)
before, _mid, after = text.partition(escaped_sep)
startlist = before.split(sep, maxsplit) # a regular split is fine here
unfinished = startlist[-1]
startlist = startlist[:-1]
# recurse because there may be more escaped separators
endlist = escape_split(after, sep, maxsplit)
# finish building the escaped value. we use endlist[0] becaue the first
# part of the string sent in recursion is the rest of the escaped value.
unfinished += sep + endlist[0]
return startlist + [unfinished] + endlist[1:] # put together all the parts
class OptionalAttr(object):
Special Optional Option that defines other attribute. Example::
def test(apiuser, userid=Optional(OAttr('apiuser')):
user = Optional.extract(userid)
# calls
def __init__(self, attr_name):
self.attr_name = attr_name
def __repr__(self):
return '<OptionalAttr:%s>' % self.attr_name
def __call__(self):
return self
# alias
OAttr = OptionalAttr
class Optional(object):
Defines an optional parameter::
param = param.getval() if isinstance(param, Optional) else param
param = param() if isinstance(param, Optional) else param
is equivalent of::
param = Optional.extract(param)
def __init__(self, type_):
self.type_ = type_
def __repr__(self):
return '<Optional:%s>' % self.type_.__repr__()
def __call__(self):
return self.getval()
def getval(self):
returns value from this Optional instance
if isinstance(self.type_, OAttr):
# use params name
return self.type_.attr_name
return self.type_
def extract(cls, val):
Extracts value from Optional() instance
:param val:
:return: original value if it's not Optional instance else
value of instance
if isinstance(val, cls):
return val.getval()
return val
def glob2re(pat):
Translate a shell PATTERN to a regular expression.
There is no way to quote meta-characters.
i, n = 0, len(pat)
res = ''
while i < n:
c = pat[i]
i = i+1
if c == '*':
#res = res + '.*'
res = res + '[^/]*'
elif c == '?':
#res = res + '.'
res = res + '[^/]'
elif c == '[':
j = i
if j < n and pat[j] == '!':
j = j+1
if j < n and pat[j] == ']':
j = j+1
while j < n and pat[j] != ']':
j = j+1
if j >= n:
res = res + '\\['
stuff = pat[i:j].replace('\\','\\\\')
i = j+1
if stuff[0] == '!':
stuff = '^' + stuff[1:]
elif stuff[0] == '^':
stuff = '\\' + stuff
res = '%s[%s]' % (res, stuff)
res = res + re.escape(c)
return res + '\Z(?ms)'
def parse_byte_string(size_str):
match = re.match(r'(\d+)(MB|KB)', size_str, re.IGNORECASE)
if not match:
raise ValueError('Given size:%s is invalid, please make sure '
'to use format of <num>(MB|KB)' % size_str)
_parts = match.groups()
num, type_ = _parts
return long(num) * {'mb': 1024*1024, 'kb': 1024}[type_.lower()]
class CachedProperty(object):
Lazy Attributes. With option to invalidate the cache by running a method
class Foo():
def heavy_func():
return 'super-calculation'
foo = Foo()
foo.heavy_func() # first computions
foo.heavy_func() # fetch from cache
# at this point calling foo.heavy_func() will be re-computed
def __init__(self, func, func_name=None):
if func_name is None:
func_name = func.__name__
self.data = (func, func_name)
update_wrapper(self, func)
def __get__(self, inst, class_):
if inst is None:
return self
func, func_name = self.data
value = func(inst)
inst.__dict__[func_name] = value
if '_invalidate_prop_cache' not in inst.__dict__:
inst.__dict__['_invalidate_prop_cache'] = partial(
self._invalidate_prop_cache, inst)
return value
def _invalidate_prop_cache(self, inst, name):
inst.__dict__.pop(name, None)