# -*- coding: utf-8 -*-
# copyright 2003-2013 LOGILAB S.A. (Paris, FRANCE), all rights reserved.
# contact http://www.logilab.fr/ -- mailto:contact@logilab.fr
#
# 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 .
"""Python modules manipulation utility functions.
:type PY_SOURCE_EXTS: tuple(str)
:var PY_SOURCE_EXTS: list of possible python source file extension
:type STD_LIB_DIR: str
:var STD_LIB_DIR: directory where standard modules are located
:type BUILTIN_MODULES: dict
:var BUILTIN_MODULES: dictionary with builtin module names has key
"""
from __future__ import with_statement
__docformat__ = "restructuredtext en"
import sys
import os
from os.path import splitext, join, abspath, isdir, dirname, exists, basename
from imp import find_module, load_module, C_BUILTIN, PY_COMPILED, PKG_DIRECTORY
from distutils.sysconfig import get_config_var, get_python_lib, get_python_version
from distutils.errors import DistutilsPlatformError
try:
import zipimport
except ImportError:
zipimport = None
ZIPFILE = object()
from logilab.common import STD_BLACKLIST, _handle_blacklist
# Notes about STD_LIB_DIR
# Consider arch-specific installation for STD_LIB_DIR definition
# :mod:`distutils.sysconfig` contains to much hardcoded values to rely on
#
# :see: `Problems with /usr/lib64 builds `_
# :see: `FHS `_
if sys.platform.startswith('win'):
PY_SOURCE_EXTS = ('py', 'pyw')
PY_COMPILED_EXTS = ('dll', 'pyd')
else:
PY_SOURCE_EXTS = ('py',)
PY_COMPILED_EXTS = ('so',)
try:
STD_LIB_DIR = get_python_lib(standard_lib=1)
# get_python_lib(standard_lib=1) is not available on pypy, set STD_LIB_DIR to
# non-valid path, see https://bugs.pypy.org/issue1164
except DistutilsPlatformError:
STD_LIB_DIR = '//'
EXT_LIB_DIR = get_python_lib()
BUILTIN_MODULES = dict(zip(sys.builtin_module_names,
[1]*len(sys.builtin_module_names)))
class NoSourceFile(Exception):
"""exception raised when we are not able to get a python
source file for a precompiled file
"""
class LazyObject(object):
def __init__(self, module, obj):
self.module = module
self.obj = obj
self._imported = None
def _getobj(self):
if self._imported is None:
self._imported = getattr(load_module_from_name(self.module),
self.obj)
return self._imported
def __getattribute__(self, attr):
try:
return super(LazyObject, self).__getattribute__(attr)
except AttributeError, ex:
return getattr(self._getobj(), attr)
def __call__(self, *args, **kwargs):
return self._getobj()(*args, **kwargs)
def load_module_from_name(dotted_name, path=None, use_sys=1):
"""Load a Python module from its name.
:type dotted_name: str
:param dotted_name: python name of a module or package
:type path: list or None
:param path:
optional list of path where the module or package should be
searched (use sys.path if nothing or None is given)
:type use_sys: bool
:param use_sys:
boolean indicating whether the sys.modules dictionary should be
used or not
:raise ImportError: if the module or package is not found
:rtype: module
:return: the loaded module
"""
return load_module_from_modpath(dotted_name.split('.'), path, use_sys)
def load_module_from_modpath(parts, path=None, use_sys=1):
"""Load a python module from its splitted name.
:type parts: list(str) or tuple(str)
:param parts:
python name of a module or package splitted on '.'
:type path: list or None
:param path:
optional list of path where the module or package should be
searched (use sys.path if nothing or None is given)
:type use_sys: bool
:param use_sys:
boolean indicating whether the sys.modules dictionary should be used or not
:raise ImportError: if the module or package is not found
:rtype: module
:return: the loaded module
"""
if use_sys:
try:
return sys.modules['.'.join(parts)]
except KeyError:
pass
modpath = []
prevmodule = None
for part in parts:
modpath.append(part)
curname = '.'.join(modpath)
module = None
if len(modpath) != len(parts):
# even with use_sys=False, should try to get outer packages from sys.modules
module = sys.modules.get(curname)
elif use_sys:
# because it may have been indirectly loaded through a parent
module = sys.modules.get(curname)
if module is None:
mp_file, mp_filename, mp_desc = find_module(part, path)
module = load_module(curname, mp_file, mp_filename, mp_desc)
if prevmodule:
setattr(prevmodule, part, module)
_file = getattr(module, '__file__', '')
if not _file and len(modpath) != len(parts):
raise ImportError('no module in %s' % '.'.join(parts[len(modpath):]) )
path = [dirname( _file )]
prevmodule = module
return module
def load_module_from_file(filepath, path=None, use_sys=1, extrapath=None):
"""Load a Python module from it's path.
:type filepath: str
:param filepath: path to the python module or package
:type path: list or None
:param path:
optional list of path where the module or package should be
searched (use sys.path if nothing or None is given)
:type use_sys: bool
:param use_sys:
boolean indicating whether the sys.modules dictionary should be
used or not
:raise ImportError: if the module or package is not found
:rtype: module
:return: the loaded module
"""
modpath = modpath_from_file(filepath, extrapath)
return load_module_from_modpath(modpath, path, use_sys)
def _check_init(path, mod_path):
"""check there are some __init__.py all along the way"""
for part in mod_path:
path = join(path, part)
if not _has_init(path):
return False
return True
def modpath_from_file(filename, extrapath=None):
"""given a file path return the corresponding splitted module's name
(i.e name of a module or package splitted on '.')
:type filename: str
:param filename: file's path for which we want the module's name
:type extrapath: dict
:param extrapath:
optional extra search path, with path as key and package name for the path
as value. This is usually useful to handle package splitted in multiple
directories using __path__ trick.
:raise ImportError:
if the corresponding module's name has not been found
:rtype: list(str)
:return: the corresponding splitted module's name
"""
base = splitext(abspath(filename))[0]
if extrapath is not None:
for path_ in extrapath:
path = abspath(path_)
if path and base[:len(path)] == path:
submodpath = [pkg for pkg in base[len(path):].split(os.sep)
if pkg]
if _check_init(path, submodpath[:-1]):
return extrapath[path_].split('.') + submodpath
for path in sys.path:
path = abspath(path)
if path and base.startswith(path):
modpath = [pkg for pkg in base[len(path):].split(os.sep) if pkg]
if _check_init(path, modpath[:-1]):
return modpath
raise ImportError('Unable to find module for %s in %s' % (
filename, ', \n'.join(sys.path)))
def file_from_modpath(modpath, path=None, context_file=None):
"""given a mod path (i.e. splitted module / package name), return the
corresponding file, giving priority to source file over precompiled
file if it exists
:type modpath: list or tuple
:param modpath:
splitted module's name (i.e name of a module or package splitted
on '.')
(this means explicit relative imports that start with dots have
empty strings in this list!)
:type path: list or None
:param path:
optional list of path where the module or package should be
searched (use sys.path if nothing or None is given)
:type context_file: str or None
:param context_file:
context file to consider, necessary if the identifier has been
introduced using a relative import unresolvable in the actual
context (i.e. modutils)
:raise ImportError: if there is no such module in the directory
:rtype: str or None
:return:
the path to the module's file or None if it's an integrated
builtin module such as 'sys'
"""
if context_file is not None:
context = dirname(context_file)
else:
context = context_file
if modpath[0] == 'xml':
# handle _xmlplus
try:
return _file_from_modpath(['_xmlplus'] + modpath[1:], path, context)
except ImportError:
return _file_from_modpath(modpath, path, context)
elif modpath == ['os', 'path']:
# FIXME: currently ignoring search_path...
return os.path.__file__
return _file_from_modpath(modpath, path, context)
def get_module_part(dotted_name, context_file=None):
"""given a dotted name return the module part of the name :
>>> get_module_part('logilab.common.modutils.get_module_part')
'logilab.common.modutils'
:type dotted_name: str
:param dotted_name: full name of the identifier we are interested in
:type context_file: str or None
:param context_file:
context file to consider, necessary if the identifier has been
introduced using a relative import unresolvable in the actual
context (i.e. modutils)
:raise ImportError: if there is no such module in the directory
:rtype: str or None
:return:
the module part of the name or None if we have not been able at
all to import the given name
XXX: deprecated, since it doesn't handle package precedence over module
(see #10066)
"""
# os.path trick
if dotted_name.startswith('os.path'):
return 'os.path'
parts = dotted_name.split('.')
if context_file is not None:
# first check for builtin module which won't be considered latter
# in that case (path != None)
if parts[0] in BUILTIN_MODULES:
if len(parts) > 2:
raise ImportError(dotted_name)
return parts[0]
# don't use += or insert, we want a new list to be created !
path = None
starti = 0
if parts[0] == '':
assert context_file is not None, \
'explicit relative import, but no context_file?'
path = [] # prevent resolving the import non-relatively
starti = 1
while parts[starti] == '': # for all further dots: change context
starti += 1
context_file = dirname(context_file)
for i in range(starti, len(parts)):
try:
file_from_modpath(parts[starti:i+1],
path=path, context_file=context_file)
except ImportError:
if not i >= max(1, len(parts) - 2):
raise
return '.'.join(parts[:i])
return dotted_name
def get_modules(package, src_directory, blacklist=STD_BLACKLIST):
"""given a package directory return a list of all available python
modules in the package and its subpackages
:type package: str
:param package: the python name for the package
:type src_directory: str
:param src_directory:
path of the directory corresponding to the package
: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 available python modules in the package and its
subpackages
"""
modules = []
for directory, dirnames, filenames in os.walk(src_directory):
_handle_blacklist(blacklist, dirnames, filenames)
# check for __init__.py
if not '__init__.py' in filenames:
dirnames[:] = ()
continue
if directory != src_directory:
dir_package = directory[len(src_directory):].replace(os.sep, '.')
modules.append(package + dir_package)
for filename in filenames:
if _is_python_file(filename) and filename != '__init__.py':
src = join(directory, filename)
module = package + src[len(src_directory):-3]
modules.append(module.replace(os.sep, '.'))
return modules
def get_module_files(src_directory, blacklist=STD_BLACKLIST):
"""given a package directory return a list of all available python
module's files in the package and its subpackages
:type src_directory: str
:param src_directory:
path of the directory corresponding to the package
: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 available python module's files in the package and
its subpackages
"""
files = []
for directory, dirnames, filenames in os.walk(src_directory):
_handle_blacklist(blacklist, dirnames, filenames)
# check for __init__.py
if not '__init__.py' in filenames:
dirnames[:] = ()
continue
for filename in filenames:
if _is_python_file(filename):
src = join(directory, filename)
files.append(src)
return files
def get_source_file(filename, include_no_ext=False):
"""given a python module's file name return the matching source file
name (the filename will be returned identically if it's a already an
absolute path to a python source file...)
:type filename: str
:param filename: python module's file name
:raise NoSourceFile: if no source file exists on the file system
:rtype: str
:return: the absolute path of the source file if it exists
"""
base, orig_ext = splitext(abspath(filename))
for ext in PY_SOURCE_EXTS:
source_path = '%s.%s' % (base, ext)
if exists(source_path):
return source_path
if include_no_ext and not orig_ext and exists(base):
return base
raise NoSourceFile(filename)
def cleanup_sys_modules(directories):
"""remove submodules of `directories` from `sys.modules`"""
cleaned = []
for modname, module in sys.modules.items():
modfile = getattr(module, '__file__', None)
if modfile:
for directory in directories:
if modfile.startswith(directory):
cleaned.append(modname)
del sys.modules[modname]
break
return cleaned
def is_python_source(filename):
"""
rtype: bool
return: True if the filename is a python source file
"""
return splitext(filename)[1][1:] in PY_SOURCE_EXTS
def is_standard_module(modname, std_path=(STD_LIB_DIR,)):
"""try to guess if a module is a standard python module (by default,
see `std_path` parameter's description)
:type modname: str
:param modname: name of the module we are interested in
:type std_path: list(str) or tuple(str)
:param std_path: list of path considered has standard
:rtype: bool
:return:
true if the module:
- is located on the path listed in one of the directory in `std_path`
- is a built-in module
"""
modname = modname.split('.')[0]
try:
filename = file_from_modpath([modname])
except ImportError, ex:
# import failed, i'm probably not so wrong by supposing it's
# not standard...
return 0
# modules which are not living in a file are considered standard
# (sys and __builtin__ for instance)
if filename is None:
return 1
filename = abspath(filename)
if filename.startswith(EXT_LIB_DIR):
return 0
for path in std_path:
if filename.startswith(abspath(path)):
return 1
return False
def is_relative(modname, from_file):
"""return true if the given module name is relative to the given
file name
:type modname: str
:param modname: name of the module we are interested in
:type from_file: str
:param from_file:
path of the module from which modname has been imported
:rtype: bool
:return:
true if the module has been imported relatively to `from_file`
"""
if not isdir(from_file):
from_file = dirname(from_file)
if from_file in sys.path:
return False
try:
find_module(modname.split('.')[0], [from_file])
return True
except ImportError:
return False
# internal only functions #####################################################
def _file_from_modpath(modpath, path=None, context=None):
"""given a mod path (i.e. splitted module / package name), return the
corresponding file
this function is used internally, see `file_from_modpath`'s
documentation for more information
"""
assert len(modpath) > 0
if context is not None:
try:
mtype, mp_filename = _module_file(modpath, [context])
except ImportError:
mtype, mp_filename = _module_file(modpath, path)
else:
mtype, mp_filename = _module_file(modpath, path)
if mtype == PY_COMPILED:
try:
return get_source_file(mp_filename)
except NoSourceFile:
return mp_filename
elif mtype == C_BUILTIN:
# integrated builtin module
return None
elif mtype == PKG_DIRECTORY:
mp_filename = _has_init(mp_filename)
return mp_filename
def _search_zip(modpath, pic):
for filepath, importer in pic.items():
if importer is not None:
if importer.find_module(modpath[0]):
if not importer.find_module('/'.join(modpath)):
raise ImportError('No module named %s in %s/%s' % (
'.'.join(modpath[1:]), filepath, modpath))
return ZIPFILE, abspath(filepath) + '/' + '/'.join(modpath), filepath
raise ImportError('No module named %s' % '.'.join(modpath))
try:
import pkg_resources
except ImportError:
pkg_resources = None
def _module_file(modpath, path=None):
"""get a module type / file path
:type modpath: list or tuple
:param modpath:
splitted module's name (i.e name of a module or package splitted
on '.'), with leading empty strings for explicit relative import
:type path: list or None
:param path:
optional list of path where the module or package should be
searched (use sys.path if nothing or None is given)
:rtype: tuple(int, str)
:return: the module type flag and the file path for a module
"""
# egg support compat
try:
pic = sys.path_importer_cache
_path = (path is None and sys.path or path)
for __path in _path:
if not __path in pic:
try:
pic[__path] = zipimport.zipimporter(__path)
except zipimport.ZipImportError:
pic[__path] = None
checkeggs = True
except AttributeError:
checkeggs = False
# pkg_resources support (aka setuptools namespace packages)
if pkg_resources is not None and modpath[0] in pkg_resources._namespace_packages and len(modpath) > 1:
# setuptools has added into sys.modules a module object with proper
# __path__, get back information from there
module = sys.modules[modpath.pop(0)]
path = module.__path__
imported = []
while modpath:
modname = modpath[0]
# take care to changes in find_module implementation wrt builtin modules
#
# Python 2.6.6 (r266:84292, Sep 11 2012, 08:34:23)
# >>> imp.find_module('posix')
# (None, 'posix', ('', '', 6))
#
# Python 3.3.1 (default, Apr 26 2013, 12:08:46)
# >>> imp.find_module('posix')
# (None, None, ('', '', 6))
try:
_, mp_filename, mp_desc = find_module(modname, path)
except ImportError:
if checkeggs:
return _search_zip(modpath, pic)[:2]
raise
else:
if checkeggs and mp_filename:
fullabspath = [abspath(x) for x in _path]
try:
pathindex = fullabspath.index(dirname(abspath(mp_filename)))
emtype, emp_filename, zippath = _search_zip(modpath, pic)
if pathindex > _path.index(zippath):
# an egg takes priority
return emtype, emp_filename
except ValueError:
# XXX not in _path
pass
except ImportError:
pass
checkeggs = False
imported.append(modpath.pop(0))
mtype = mp_desc[2]
if modpath:
if mtype != PKG_DIRECTORY:
raise ImportError('No module %s in %s' % ('.'.join(modpath),
'.'.join(imported)))
# XXX guess if package is using pkgutil.extend_path by looking for
# those keywords in the first four Kbytes
try:
with open(join(mp_filename, '__init__.py')) as stream:
data = stream.read(4096)
except IOError:
path = [mp_filename]
else:
if 'pkgutil' in data and 'extend_path' in data:
# extend_path is called, search sys.path for module/packages
# of this name see pkgutil.extend_path documentation
path = [join(p, *imported) for p in sys.path
if isdir(join(p, *imported))]
else:
path = [mp_filename]
return mtype, mp_filename
def _is_python_file(filename):
"""return true if the given filename should be considered as a python file
.pyc and .pyo are ignored
"""
for ext in ('.py', '.so', '.pyd', '.pyw'):
if filename.endswith(ext):
return True
return False
def _has_init(directory):
"""if the given directory has a valid __init__ file, return its path,
else return None
"""
mod_or_pack = join(directory, '__init__')
for ext in PY_SOURCE_EXTS + ('pyc', 'pyo'):
if exists(mod_or_pack + '.' + ext):
return mod_or_pack + '.' + ext
return None