# copyright 2003-2014 LOGILAB S.A. (Paris, FRANCE), all rights reserved.
# contact http://www.logilab.fr/ -- mailto:[email protected]
#
# This file is part of logilab-common.
#
# logilab-common is free software: you can redistribute it and/or modify it under
# the terms of the GNU Lesser General Public License as published by the Free
# Software Foundation, either version 2.1 of the License, or (at your option) any
# later version.
#
# logilab-common is distributed in the hope that it will be useful, but WITHOUT
# ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
# FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License for more
# details.
#
# You should have received a copy of the GNU Lesser General Public License along
# with logilab-common. If not, see <http://www.gnu.org/licenses/>.
"""shell/term utilities, useful to write some python scripts instead of shell
scripts.
"""
from __future__ import print_function
__docformat__ = "restructuredtext en"
import os
import glob
import shutil
import stat
import sys
import tempfile
import time
import fnmatch
import errno
import string
import random
import subprocess
from os.path import exists, isdir, islink, basename, join
from six import string_types
from six.moves import range, input as raw_input
from logilab.common import STD_BLACKLIST, _handle_blacklist
from logilab.common.compat import str_to_bytes
from logilab.common.deprecation import deprecated
try:
from logilab.common.proc import ProcInfo, NoSuchProcess
except ImportError:
# windows platform
class NoSuchProcess(Exception): pass
def ProcInfo(pid):
raise NoSuchProcess()
class tempdir(object):
def __enter__(self):
self.path = tempfile.mkdtemp()
return self.path
def __exit__(self, exctype, value, traceback):
# rmtree in all cases
shutil.rmtree(self.path)
return traceback is None
class pushd(object):
def __init__(self, directory):
self.directory = directory
def __enter__(self):
self.cwd = os.getcwd()
os.chdir(self.directory)
return self.directory
def __exit__(self, exctype, value, traceback):
os.chdir(self.cwd)
def chown(path, login=None, group=None):
"""Same as `os.chown` function but accepting user login or group name as
argument. If login or group is omitted, it's left unchanged.
Note: you must own the file to chown it (or be root). Otherwise OSError is raised.
"""
if login is None:
uid = -1
else:
try:
uid = int(login)
except ValueError:
import pwd # Platforms: Unix
uid = pwd.getpwnam(login).pw_uid
if group is None:
gid = -1
else:
try:
gid = int(group)
except ValueError:
import grp
gid = grp.getgrnam(group).gr_gid
os.chown(path, uid, gid)
def mv(source, destination, _action=shutil.move):
"""A shell-like mv, supporting wildcards.
"""
sources = glob.glob(source)
if len(sources) > 1:
assert isdir(destination)
for filename in sources:
_action(filename, join(destination, basename(filename)))
else:
try:
source = sources[0]
except IndexError:
raise OSError('No file matching %s' % source)
if isdir(destination) and exists(destination):
destination = join(destination, basename(source))
try:
_action(source, destination)
except OSError as ex:
raise OSError('Unable to move %r to %r (%s)' % (
source, destination, ex))
def rm(*files):
"""A shell-like rm, supporting wildcards.
"""
for wfile in files:
for filename in glob.glob(wfile):
if islink(filename):
os.remove(filename)
elif isdir(filename):
shutil.rmtree(filename)
else:
os.remove(filename)
def cp(source, destination):
"""A shell-like cp, supporting wildcards.
"""
mv(source, destination, _action=shutil.copy)
def find(directory, exts, exclude=False, blacklist=STD_BLACKLIST):
"""Recursively find files ending with the given extensions from the directory.
:type directory: str
:param directory:
directory where the search should start
:type exts: basestring or list or tuple
:param exts:
extensions or lists or extensions to search
:type exclude: boolean
:param exts:
if this argument is True, returning files NOT ending with the given
extensions
:type blacklist: list or tuple
:param blacklist:
optional list of files or directory to ignore, default to the value of
`logilab.common.STD_BLACKLIST`
:rtype: list
:return:
the list of all matching files
"""
if isinstance(exts, string_types):
exts = (exts,)
if exclude:
def match(filename, exts):
for ext in exts:
if filename.endswith(ext):
return False
return True
else:
def match(filename, exts):
for ext in exts:
if filename.endswith(ext):
return True
return False
files = []
for dirpath, dirnames, filenames in os.walk(directory):
_handle_blacklist(blacklist, dirnames, filenames)
# don't append files if the directory is blacklisted
dirname = basename(dirpath)
if dirname in blacklist:
continue
files.extend([join(dirpath, f) for f in filenames if match(f, exts)])
return files
def globfind(directory, pattern, blacklist=STD_BLACKLIST):
"""Recursively finds files matching glob `pattern` under `directory`.
This is an alternative to `logilab.common.shellutils.find`.
:type directory: str
:param directory:
directory where the search should start
:type pattern: basestring
:param pattern:
the glob pattern (e.g *.py, foo*.py, etc.)
:type blacklist: list or tuple
:param blacklist:
optional list of files or directory to ignore, default to the value of
`logilab.common.STD_BLACKLIST`
:rtype: iterator
:return:
iterator over the list of all matching files
"""
for curdir, dirnames, filenames in os.walk(directory):
_handle_blacklist(blacklist, dirnames, filenames)
for fname in fnmatch.filter(filenames, pattern):
yield join(curdir, fname)
def unzip(archive, destdir):
import zipfile
if not exists(destdir):
os.mkdir(destdir)
zfobj = zipfile.ZipFile(archive)
for name in zfobj.namelist():
if name.endswith('/'):
os.mkdir(join(destdir, name))
else:
outfile = open(join(destdir, name), 'wb')
outfile.write(zfobj.read(name))
outfile.close()
class Execute:
"""This is a deadlock safe version of popen2 (no stdin), that returns
an object with errorlevel, out and err.
"""
def __init__(self, command):
cmd = subprocess.Popen(command, shell=True, stdout=subprocess.PIPE, stderr=subprocess.PIPE)
self.out, self.err = cmd.communicate()
self.status = os.WEXITSTATUS(cmd.returncode)
Execute = deprecated('Use subprocess.Popen instead')(Execute)
def acquire_lock(lock_file, max_try=10, delay=10, max_delay=3600):
"""Acquire a lock represented by a file on the file system
If the process written in lock file doesn't exist anymore, we remove the
lock file immediately
If age of the lock_file is greater than max_delay, then we raise a UserWarning
"""
count = abs(max_try)
while count:
try:
fd = os.open(lock_file, os.O_EXCL | os.O_RDWR | os.O_CREAT)
os.write(fd, str_to_bytes(str(os.getpid())) )
os.close(fd)
return True
except OSError as e:
if e.errno == errno.EEXIST:
try:
fd = open(lock_file, "r")
pid = int(fd.readline())
pi = ProcInfo(pid)
age = (time.time() - os.stat(lock_file)[stat.ST_MTIME])
if age / max_delay > 1 :
raise UserWarning("Command '%s' (pid %s) has locked the "
"file '%s' for %s minutes"
% (pi.name(), pid, lock_file, age/60))
except UserWarning:
raise
except NoSuchProcess:
os.remove(lock_file)
except Exception:
# The try block is not essential. can be skipped.
# Note: ProcInfo object is only available for linux
# process information are not accessible...
# or lock_file is no more present...
pass
else:
raise
count -= 1
time.sleep(delay)
else:
raise Exception('Unable to acquire %s' % lock_file)
def release_lock(lock_file):
"""Release a lock represented by a file on the file system."""
os.remove(lock_file)
class ProgressBar(object):
"""A simple text progression bar."""
def __init__(self, nbops, size=20, stream=sys.stdout, title=''):
if title:
self._fstr = '\r%s [%%-%ss]' % (title, int(size))
else:
self._fstr = '\r[%%-%ss]' % int(size)
self._stream = stream
self._total = nbops
self._size = size
self._current = 0
self._progress = 0
self._current_text = None
self._last_text_write_size = 0
def _get_text(self):
return self._current_text
def _set_text(self, text=None):
if text != self._current_text:
self._current_text = text
self.refresh()
def _del_text(self):
self.text = None
text = property(_get_text, _set_text, _del_text)
def update(self, offset=1, exact=False):
"""Move FORWARD to new cursor position (cursor will never go backward).
:offset: fraction of ``size``
:exact:
- False: offset relative to current cursor position if True
- True: offset as an asbsolute position
"""
if exact:
self._current = offset
else:
self._current += offset
progress = int((float(self._current)/float(self._total))*self._size)
if progress > self._progress:
self._progress = progress
self.refresh()
def refresh(self):
"""Refresh the progression bar display."""
self._stream.write(self._fstr % ('=' * min(self._progress, self._size)) )
if self._last_text_write_size or self._current_text:
template = ' %%-%is' % (self._last_text_write_size)
text = self._current_text
if text is None:
text = ''
self._stream.write(template % text)
self._last_text_write_size = len(text.rstrip())
self._stream.flush()
def finish(self):
self._stream.write('\n')
self._stream.flush()
class DummyProgressBar(object):
__slot__ = ('text',)
def refresh(self):
pass
def update(self):
pass
def finish(self):
pass
_MARKER = object()
class progress(object):
def __init__(self, nbops=_MARKER, size=_MARKER, stream=_MARKER, title=_MARKER, enabled=True):
self.nbops = nbops
self.size = size
self.stream = stream
self.title = title
self.enabled = enabled
def __enter__(self):
if self.enabled:
kwargs = {}
for attr in ('nbops', 'size', 'stream', 'title'):
value = getattr(self, attr)
if value is not _MARKER:
kwargs[attr] = value
self.pb = ProgressBar(**kwargs)
else:
self.pb = DummyProgressBar()
return self.pb
def __exit__(self, exc_type, exc_val, exc_tb):
self.pb.finish()
class RawInput(object):
def __init__(self, input=None, printer=None):
self._input = input or raw_input
self._print = printer
def ask(self, question, options, default):
assert default in options
choices = []
for option in options:
if option == default:
label = option[0].upper()
else:
label = option[0].lower()
if len(option) > 1:
label += '(%s)' % option[1:].lower()
choices.append((option, label))
prompt = "%s [%s]: " % (question,
'/'.join([opt[1] for opt in choices]))
tries = 3
while tries > 0:
answer = self._input(prompt).strip().lower()
if not answer:
return default
possible = [option for option, label in choices
if option.lower().startswith(answer)]
if len(possible) == 1:
return possible[0]
elif len(possible) == 0:
msg = '%s is not an option.' % answer
else:
msg = ('%s is an ambiguous answer, do you mean %s ?' % (
answer, ' or '.join(possible)))
if self._print:
self._print(msg)
else:
print(msg)
tries -= 1
raise Exception('unable to get a sensible answer')
def confirm(self, question, default_is_yes=True):
default = default_is_yes and 'y' or 'n'
answer = self.ask(question, ('y', 'n'), default)
return answer == 'y'
ASK = RawInput()
def getlogin():
"""avoid using os.getlogin() because of strange tty / stdin problems
(man 3 getlogin)
Another solution would be to use $LOGNAME, $USER or $USERNAME
"""
if sys.platform != 'win32':
import pwd # Platforms: Unix
return pwd.getpwuid(os.getuid())[0]
else:
return os.environ['USERNAME']
def generate_password(length=8, vocab=string.ascii_letters + string.digits):
"""dumb password generation function"""
pwd = ''
for i in range(length):
pwd += random.choice(vocab)
return pwd