Python - ez setup.py

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ez_setup.py

https://bootstrap.pypa.io/ez_setup.py


#!/usr/bin/env python

"""
Setuptools bootstrapping installer.

Run this script to install or upgrade setuptools.
"""

import os
import shutil
import sys
import tempfile
import zipfile
import optparse
import subprocess
import platform
import textwrap
import contextlib
import warnings

from distutils import log

try:
    from urllib.request import urlopen
except ImportError:
    from urllib2 import urlopen

try:
    from site import USER_SITE
except ImportError:
    USER_SITE = None

DEFAULT_VERSION = "15.0"
DEFAULT_URL = "https://pypi.python.org/packages/source/s/setuptools/"
DEFAULT_SAVE_DIR = os.curdir


def _python_cmd(*args):
    """
    Execute a command.

    Return True if the command succeeded.
    """
    args = (sys.executable,) + args
    return subprocess.call(args) == 0


def _install(archive_filename, install_args=()):
    """Install Setuptools."""
    with archive_context(archive_filename):
        # installing
        log.warn('Installing Setuptools')
        if not _python_cmd('setup.py', 'install', *install_args):
            log.warn('Something went wrong during the installation.')
            log.warn('See the error message above.')
            # exitcode will be 2
            return 2


def _build_egg(egg, archive_filename, to_dir):
    """Build Setuptools egg."""
    with archive_context(archive_filename):
        # building an egg
        log.warn('Building a Setuptools egg in %s', to_dir)
        _python_cmd('setup.py', '-q', 'bdist_egg', '--dist-dir', to_dir)
    # returning the result
    log.warn(egg)
    if not os.path.exists(egg):
        raise IOError('Could not build the egg.')


class ContextualZipFile(zipfile.ZipFile):

    """Supplement ZipFile class to support context manager for Python 2.6."""

    def __enter__(self):
        return self

    def __exit__(self, type, value, traceback):
        self.close()

    def __new__(cls, *args, **kwargs):
        """Construct a ZipFile or ContextualZipFile as appropriate."""
        if hasattr(zipfile.ZipFile, '__exit__'):
            return zipfile.ZipFile(*args, **kwargs)
        return super(ContextualZipFile, cls).__new__(cls)


@contextlib.contextmanager
def archive_context(filename):
    """
    Unzip filename to a temporary directory, set to the cwd.

    The unzipped target is cleaned up after.
    """
    tmpdir = tempfile.mkdtemp()
    log.warn('Extracting in %s', tmpdir)
    old_wd = os.getcwd()
    try:
        os.chdir(tmpdir)
        with ContextualZipFile(filename) as archive:
            archive.extractall()

        # going in the directory
        subdir = os.path.join(tmpdir, os.listdir(tmpdir)[0])
        os.chdir(subdir)
        log.warn('Now working in %s', subdir)
        yield

    finally:
        os.chdir(old_wd)
        shutil.rmtree(tmpdir)


def _do_download(version, download_base, to_dir, download_delay):
    """Download Setuptools."""
    egg = os.path.join(to_dir, 'setuptools-%s-py%d.%d.egg'
                       % (version, sys.version_info[0], sys.version_info[1]))
    if not os.path.exists(egg):
        archive = download_setuptools(version, download_base,
                                      to_dir, download_delay)
        _build_egg(egg, archive, to_dir)
    sys.path.insert(0, egg)

    # Remove previously-imported pkg_resources if present (see
    # https://bitbucket.org/pypa/setuptools/pull-request/7/ for details).
    if 'pkg_resources' in sys.modules:
        del sys.modules['pkg_resources']

    import setuptools
    setuptools.bootstrap_install_from = egg


def use_setuptools(
        version=DEFAULT_VERSION, download_base=DEFAULT_URL,
        to_dir=DEFAULT_SAVE_DIR, download_delay=15):
    """
    Ensure that a setuptools version is installed.

    Return None. Raise SystemExit if the requested version
    or later cannot be installed.
    """
    to_dir = os.path.abspath(to_dir)

    # prior to importing, capture the module state for
    # representative modules.
    rep_modules = 'pkg_resources', 'setuptools'
    imported = set(sys.modules).intersection(rep_modules)

    try:
        import pkg_resources
        pkg_resources.require("setuptools>=" + version)
        # a suitable version is already installed
        return
    except ImportError:
        # pkg_resources not available; setuptools is not installed; download
        pass
    except pkg_resources.DistributionNotFound:
        # no version of setuptools was found; allow download
        pass
    except pkg_resources.VersionConflict as VC_err:
        if imported:
            _conflict_bail(VC_err, version)

        # otherwise, unload pkg_resources to allow the downloaded version to
        #  take precedence.
        del pkg_resources
        _unload_pkg_resources()

    return _do_download(version, download_base, to_dir, download_delay)


def _conflict_bail(VC_err, version):
    """
    Setuptools was imported prior to invocation, so it is
    unsafe to unload it. Bail out.
    """
    conflict_tmpl = textwrap.dedent("""
        The required version of setuptools (>={version}) is not available,
        and can't be installed while this script is running. Please
        install a more recent version first, using
        'easy_install -U setuptools'.

        (Currently using {VC_err.args[0]!r})
        """)
    msg = conflict_tmpl.format(**locals())
    sys.stderr.write(msg)
    sys.exit(2)


def _unload_pkg_resources():
    del_modules = [
        name for name in sys.modules
        if name.startswith('pkg_resources')
    ]
    for mod_name in del_modules:
        del sys.modules[mod_name]


def _clean_check(cmd, target):
    """
    Run the command to download target.

    If the command fails, clean up before re-raising the error.
    """
    try:
        subprocess.check_call(cmd)
    except subprocess.CalledProcessError:
        if os.access(target, os.F_OK):
            os.unlink(target)
        raise


def download_file_powershell(url, target):
    """
    Download the file at url to target using Powershell.

    Powershell will validate trust.
    Raise an exception if the command cannot complete.
    """
    target = os.path.abspath(target)
    ps_cmd = (
        "[System.Net.WebRequest]::DefaultWebProxy.Credentials = "
        "[System.Net.CredentialCache]::DefaultCredentials; "
        "(new-object System.Net.WebClient).DownloadFile(%(url)r, %(target)r)"
        % vars()
    )
    cmd = [
        'powershell',
        '-Command',
        ps_cmd,
    ]
    _clean_check(cmd, target)


def has_powershell():
    """Determine if Powershell is available."""
    if platform.system() != 'Windows':
        return False
    cmd = ['powershell', '-Command', 'echo test']
    with open(os.path.devnull, 'wb') as devnull:
        try:
            subprocess.check_call(cmd, stdout=devnull, stderr=devnull)
        except Exception:
            return False
    return True
download_file_powershell.viable = has_powershell


def download_file_curl(url, target):
    cmd = ['curl', url, '--silent', '--output', target]
    _clean_check(cmd, target)


def has_curl():
    cmd = ['curl', '--version']
    with open(os.path.devnull, 'wb') as devnull:
        try:
            subprocess.check_call(cmd, stdout=devnull, stderr=devnull)
        except Exception:
            return False
    return True
download_file_curl.viable = has_curl


def download_file_wget(url, target):
    cmd = ['wget', url, '--quiet', '--output-document', target]
    _clean_check(cmd, target)


def has_wget():
    cmd = ['wget', '--version']
    with open(os.path.devnull, 'wb') as devnull:
        try:
            subprocess.check_call(cmd, stdout=devnull, stderr=devnull)
        except Exception:
            return False
    return True
download_file_wget.viable = has_wget


def download_file_insecure(url, target):
    """Use Python to download the file, without connection authentication."""
    src = urlopen(url)
    try:
        # Read all the data in one block.
        data = src.read()
    finally:
        src.close()

    # Write all the data in one block to avoid creating a partial file.
    with open(target, "wb") as dst:
        dst.write(data)
download_file_insecure.viable = lambda: True


def get_best_downloader():
    downloaders = (
        download_file_powershell,
        download_file_curl,
        download_file_wget,
        download_file_insecure,
    )
    viable_downloaders = (dl for dl in downloaders if dl.viable())
    return next(viable_downloaders, None)


def download_setuptools(
        version=DEFAULT_VERSION, download_base=DEFAULT_URL,
        to_dir=DEFAULT_SAVE_DIR, delay=15,
        downloader_factory=get_best_downloader):
    """
    Download setuptools from a specified location and return its filename.

    `version` should be a valid setuptools version number that is available
    as an sdist for download under the `download_base` URL (which should end
    with a '/'). `to_dir` is the directory where the egg will be downloaded.
    `delay` is the number of seconds to pause before an actual download
    attempt.

    ``downloader_factory`` should be a function taking no arguments and
    returning a function for downloading a URL to a target.
    """
    # making sure we use the absolute path
    to_dir = os.path.abspath(to_dir)
    zip_name = "setuptools-%s.zip" % version
    url = download_base + zip_name
    saveto = os.path.join(to_dir, zip_name)
    if not os.path.exists(saveto):  # Avoid repeated downloads
        log.warn("Downloading %s", url)
        downloader = downloader_factory()
        downloader(url, saveto)
    return os.path.realpath(saveto)


def _build_install_args(options):
    """
    Build the arguments to 'python setup.py install' on the setuptools package.

    Returns list of command line arguments.
    """
    return ['--user'] if options.user_install else []


def _parse_args():
    """Parse the command line for options."""
    parser = optparse.OptionParser()
    parser.add_option(
        '--user', dest='user_install', action='store_true', default=False,
        help='install in user site package (requires Python 2.6 or later)')
    parser.add_option(
        '--download-base', dest='download_base', metavar="URL",
        default=DEFAULT_URL,
        help='alternative URL from where to download the setuptools package')
    parser.add_option(
        '--insecure', dest='downloader_factory', action='store_const',
        const=lambda: download_file_insecure, default=get_best_downloader,
        help='Use internal, non-validating downloader'
    )
    parser.add_option(
        '--version', help="Specify which version to download",
        default=DEFAULT_VERSION,
    )
    parser.add_option(
    	'--to-dir',
    	help="Directory to save (and re-use) package",
    	default=DEFAULT_SAVE_DIR,
    )
    options, args = parser.parse_args()
    # positional arguments are ignored
    return options


def _download_args(options):
	"""Return args for download_setuptools function from cmdline args."""
	return dict(
		version=options.version,
		download_base=options.download_base,
		downloader_factory=options.downloader_factory,
		to_dir=options.to_dir,
	)


def main():
    """Install or upgrade setuptools and EasyInstall."""
    options = _parse_args()
    archive = download_setuptools(**_download_args(options))
    return _install(archive, _build_install_args(options))

if __name__ == '__main__':
    sys.exit(main())

Other

#!/usr/bin/env python
"""Bootstrap setuptools installation

To use setuptools in your package's setup.py, include this
file in the same directory and add this to the top of your setup.py::

    from ez_setup import use_setuptools
    use_setuptools()

To require a specific version of setuptools, set a download
mirror, or use an alternate download directory, simply supply
the appropriate options to ``use_setuptools()``.

This file can also be run as a script to install or upgrade setuptools.
"""
import os
import shutil
import sys
import tempfile
import tarfile
import optparse
import subprocess
import platform
import textwrap

from distutils import log

try:
    from site import USER_SITE
except ImportError:
    USER_SITE = None

DEFAULT_VERSION = "2.1"
DEFAULT_URL = "https://pypi.python.org/packages/source/s/setuptools/"

def _python_cmd(*args):
    args = (sys.executable,) + args
    return subprocess.call(args) == 0

def _install(tarball, install_args=()):
    # extracting the tarball
    tmpdir = tempfile.mkdtemp()
    log.warn('Extracting in %s', tmpdir)
    old_wd = os.getcwd()
    try:
        os.chdir(tmpdir)
        tar = tarfile.open(tarball)
        _extractall(tar)
        tar.close()

        # going in the directory
        subdir = os.path.join(tmpdir, os.listdir(tmpdir)[0])
        os.chdir(subdir)
        log.warn('Now working in %s', subdir)

        # installing
        log.warn('Installing Setuptools')
        if not _python_cmd('setup.py', 'install', *install_args):
            log.warn('Something went wrong during the installation.')
            log.warn('See the error message above.')
            # exitcode will be 2
            return 2
    finally:
        os.chdir(old_wd)
        shutil.rmtree(tmpdir)


def _build_egg(egg, tarball, to_dir):
    # extracting the tarball
    tmpdir = tempfile.mkdtemp()
    log.warn('Extracting in %s', tmpdir)
    old_wd = os.getcwd()
    try:
        os.chdir(tmpdir)
        tar = tarfile.open(tarball)
        _extractall(tar)
        tar.close()

        # going in the directory
        subdir = os.path.join(tmpdir, os.listdir(tmpdir)[0])
        os.chdir(subdir)
        log.warn('Now working in %s', subdir)

        # building an egg
        log.warn('Building a Setuptools egg in %s', to_dir)
        _python_cmd('setup.py', '-q', 'bdist_egg', '--dist-dir', to_dir)

    finally:
        os.chdir(old_wd)
        shutil.rmtree(tmpdir)
    # returning the result
    log.warn(egg)
    if not os.path.exists(egg):
        raise IOError('Could not build the egg.')


def _do_download(version, download_base, to_dir, download_delay):
    egg = os.path.join(to_dir, 'setuptools-%s-py%d.%d.egg'
                       % (version, sys.version_info[0], sys.version_info[1]))
    if not os.path.exists(egg):
        tarball = download_setuptools(version, download_base,
                                      to_dir, download_delay)
        _build_egg(egg, tarball, to_dir)
    sys.path.insert(0, egg)

    # Remove previously-imported pkg_resources if present (see
    # https://bitbucket.org/pypa/setuptools/pull-request/7/ for details).
    if 'pkg_resources' in sys.modules:
        del sys.modules['pkg_resources']

    import setuptools
    setuptools.bootstrap_install_from = egg


def use_setuptools(version=DEFAULT_VERSION, download_base=DEFAULT_URL,
                   to_dir=os.curdir, download_delay=15):
    to_dir = os.path.abspath(to_dir)
    rep_modules = 'pkg_resources', 'setuptools'
    imported = set(sys.modules).intersection(rep_modules)
    try:
        import pkg_resources
    except ImportError:
        return _do_download(version, download_base, to_dir, download_delay)
    try:
        pkg_resources.require("setuptools>=" + version)
        return
    except pkg_resources.DistributionNotFound:
        return _do_download(version, download_base, to_dir, download_delay)
    except pkg_resources.VersionConflict as VC_err:
        if imported:
            msg = textwrap.dedent("""
                The required version of setuptools (>={version}) is not available,
                and can't be installed while this script is running. Please
                install a more recent version first, using
                'easy_install -U setuptools'.

                (Currently using {VC_err.args[0]!r})
                """).format(VC_err=VC_err, version=version)
            sys.stderr.write(msg)
            sys.exit(2)

        # otherwise, reload ok
        del pkg_resources, sys.modules['pkg_resources']
        return _do_download(version, download_base, to_dir, download_delay)

def _clean_check(cmd, target):
    """
    Run the command to download target. If the command fails, clean up before
    re-raising the error.
    """
    try:
        subprocess.check_call(cmd)
    except subprocess.CalledProcessError:
        if os.access(target, os.F_OK):
            os.unlink(target)
        raise

def download_file_powershell(url, target):
    """
    Download the file at url to target using Powershell (which will validate
    trust). Raise an exception if the command cannot complete.
    """
    target = os.path.abspath(target)
    cmd = [
        'powershell',
        '-Command',
        "(new-object System.Net.WebClient).DownloadFile(%(url)r, %(target)r)" % vars(),
    ]
    _clean_check(cmd, target)

def has_powershell():
    if platform.system() != 'Windows':
        return False
    cmd = ['powershell', '-Command', 'echo test']
    devnull = open(os.path.devnull, 'wb')
    try:
        try:
            subprocess.check_call(cmd, stdout=devnull, stderr=devnull)
        except:
            return False
    finally:
        devnull.close()
    return True

download_file_powershell.viable = has_powershell

def download_file_curl(url, target):
    cmd = ['curl', url, '--silent', '--output', target]
    _clean_check(cmd, target)

def has_curl():
    cmd = ['curl', '--version']
    devnull = open(os.path.devnull, 'wb')
    try:
        try:
            subprocess.check_call(cmd, stdout=devnull, stderr=devnull)
        except:
            return False
    finally:
        devnull.close()
    return True

download_file_curl.viable = has_curl

def download_file_wget(url, target):
    cmd = ['wget', url, '--quiet', '--output-document', target]
    _clean_check(cmd, target)

def has_wget():
    cmd = ['wget', '--version']
    devnull = open(os.path.devnull, 'wb')
    try:
        try:
            subprocess.check_call(cmd, stdout=devnull, stderr=devnull)
        except:
            return False
    finally:
        devnull.close()
    return True

download_file_wget.viable = has_wget

def download_file_insecure(url, target):
    """
    Use Python to download the file, even though it cannot authenticate the
    connection.
    """
    try:
        from urllib.request import urlopen
    except ImportError:
        from urllib2 import urlopen
    src = dst = None
    try:
        src = urlopen(url)
        # Read/write all in one block, so we don't create a corrupt file
        # if the download is interrupted.
        data = src.read()
        dst = open(target, "wb")
        dst.write(data)
    finally:
        if src:
            src.close()
        if dst:
            dst.close()

download_file_insecure.viable = lambda: True

def get_best_downloader():
    downloaders = [
        download_file_powershell,
        download_file_curl,
        download_file_wget,
        download_file_insecure,
    ]

    for dl in downloaders:
        if dl.viable():
            return dl

def download_setuptools(version=DEFAULT_VERSION, download_base=DEFAULT_URL,
                        to_dir=os.curdir, delay=15,
                        downloader_factory=get_best_downloader):
    """Download setuptools from a specified location and return its filename

    `version` should be a valid setuptools version number that is available
    as an egg for download under the `download_base` URL (which should end
    with a '/'). `to_dir` is the directory where the egg will be downloaded.
    `delay` is the number of seconds to pause before an actual download
    attempt.

    ``downloader_factory`` should be a function taking no arguments and
    returning a function for downloading a URL to a target.
    """
    # making sure we use the absolute path
    to_dir = os.path.abspath(to_dir)
    tgz_name = "setuptools-%s.tar.gz" % version
    url = download_base + tgz_name
    saveto = os.path.join(to_dir, tgz_name)
    if not os.path.exists(saveto):  # Avoid repeated downloads
        log.warn("Downloading %s", url)
        downloader = downloader_factory()
        downloader(url, saveto)
    return os.path.realpath(saveto)


def _extractall(self, path=".", members=None):
    """Extract all members from the archive to the current working
       directory and set owner, modification time and permissions on
       directories afterwards. `path' specifies a different directory
       to extract to. `members' is optional and must be a subset of the
       list returned by getmembers().
    """
    import copy
    import operator
    from tarfile import ExtractError
    directories = []

    if members is None:
        members = self

    for tarinfo in members:
        if tarinfo.isdir():
            # Extract directories with a safe mode.
            directories.append(tarinfo)
            tarinfo = copy.copy(tarinfo)
            tarinfo.mode = 448  # decimal for oct 0700
        self.extract(tarinfo, path)

    # Reverse sort directories.
    directories.sort(key=operator.attrgetter('name'), reverse=True)

    # Set correct owner, mtime and filemode on directories.
    for tarinfo in directories:
        dirpath = os.path.join(path, tarinfo.name)
        try:
            self.chown(tarinfo, dirpath)
            self.utime(tarinfo, dirpath)
            self.chmod(tarinfo, dirpath)
        except ExtractError as e:
            if self.errorlevel > 1:
                raise
            else:
                self._dbg(1, "tarfile: %s" % e)


def _build_install_args(options):
    """
    Build the arguments to 'python setup.py install' on the setuptools package
    """
    return ['--user'] if options.user_install else []

def _parse_args():
    """
    Parse the command line for options
    """
    parser = optparse.OptionParser()
    parser.add_option(
        '--user', dest='user_install', action='store_true', default=False,
        help='install in user site package (requires Python 2.6 or later)')
    parser.add_option(
        '--download-base', dest='download_base', metavar="URL",
        default=DEFAULT_URL,
        help='alternative URL from where to download the setuptools package')
    parser.add_option(
        '--insecure', dest='downloader_factory', action='store_const',
        const=lambda: download_file_insecure, default=get_best_downloader,
        help='Use internal, non-validating downloader'
    )
    options, args = parser.parse_args()
    # positional arguments are ignored
    return options

def main(version=DEFAULT_VERSION):
    """Install or upgrade setuptools and EasyInstall"""
    options = _parse_args()
    tarball = download_setuptools(download_base=options.download_base,
        downloader_factory=options.downloader_factory)
    return _install(tarball, _build_install_args(options))

if __name__ == '__main__':
    sys.exit(main())