bootstrap.py

##############################################################################
#
# Copyright (c) 2006 Zope Foundation and Contributors.
# All Rights Reserved.
#
# This software is subject to the provisions of the Zope Public License,
# Version 2.1 (ZPL).  A copy of the ZPL should accompany this distribution.
# THIS SOFTWARE IS PROVIDED "AS IS" AND ANY AND ALL EXPRESS OR IMPLIED
# WARRANTIES ARE DISCLAIMED, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
# WARRANTIES OF TITLE, MERCHANTABILITY, AGAINST INFRINGEMENT, AND FITNESS
# FOR A PARTICULAR PURPOSE.
#
##############################################################################
"""Bootstrap a buildout-based project

Simply run this script in a directory containing a buildout.cfg.
The script accepts buildout command-line options, so you can
use the -c option to specify an alternate configuration file.

$Id$
"""

import os
import shutil
import sys
import tempfile
import textwrap
import urllib
import urllib2

from optparse import OptionParser

if sys.platform == 'win32':

    def quote(c):
        if ' ' in c:
            return '"%s"' % c  # work around spawn lamosity on windows
        else:
            return c
else:
    quote = str

# In order to be more robust in the face of system Pythons, we want to
# run without site-packages loaded.  This is somewhat tricky, in
# particular because Python 2.6's distutils imports site, so starting
# with the -S flag is not sufficient.  However, we'll start with that:
if 'site' in sys.modules:
    # We will restart with python -S.
    args = sys.argv[:]
    args[0:0] = [sys.executable, '-S']
    args = map(quote, args)
    os.execv(sys.executable, args)
# Now we are running with -S.  We'll get the clean sys.path, import site
# because distutils will do it later, and then reset the path and clean
# out any namespace packages from site-packages that might have been
# loaded by .pth files.
clean_path = sys.path[:]
import site
sys.path[:] = clean_path
for k, v in sys.modules.items():
    if (hasattr(v, '__path__') and
        len(v.__path__) == 1 and
        not os.path.exists(os.path.join(v.__path__[0], '__init__.py'))):
        # This is a namespace package.  Remove it.
        sys.modules.pop(k)

is_jython = sys.platform.startswith('java')

setuptools_source = 'http://peak.telecommunity.com/dist/ez_setup.py'
distribute_source = 'http://python-distribute.org/distribute_setup.py'


# parsing arguments
def normalize_to_url(option, opt_str, value, parser):
    if value:
        if '://' not in value:  # It doesn't smell like a URL.
            value = 'file://%s' % (
                urllib.pathname2url(
                    os.path.abspath(os.path.expanduser(value))),)
        if opt_str == '--download-base' and not value.endswith('/'):
            # Download base needs a trailing slash to make the world happy.
            value += '/'
    else:
        value = None
    name = opt_str[2:].replace('-', '_')
    setattr(parser.values, name, value)

usage = '''\
[DESIRED PYTHON FOR BUILDOUT] bootstrap.py [options]

Bootstraps a buildout-based project.

Simply run this script in a directory containing a buildout.cfg, using the
Python that you want bin/buildout to use.

Note that by using --setup-source and --download-base to point to
local resources, you can keep this script from going over the network.
'''

parser = OptionParser(usage=usage)
parser.add_option("-v", "--version", dest="version",
                          help="use a specific zc.buildout version")
parser.add_option("-d", "--distribute",
                   action="store_true", dest="use_distribute", default=False,
                   help="Use Distribute rather than Setuptools.")
parser.add_option("--setup-source", action="callback", dest="setup_source",
                  callback=normalize_to_url, nargs=1, type="string",
                  help=("Specify a URL or file location for the setup file. "
                        "If you use Setuptools, this will default to " +
                        setuptools_source + "; if you use Distribute, this "
                        "will default to " + distribute_source + "."))
parser.add_option("--download-base", action="callback", dest="download_base",
                  callback=normalize_to_url, nargs=1, type="string",
                  help=("Specify a URL or directory for downloading "
                        "zc.buildout and either Setuptools or Distribute. "
                        "Defaults to PyPI."))
parser.add_option("--eggs",
                  help=("Specify a directory for storing eggs.  Defaults to "
                        "a temporary directory that is deleted when the "
                        "bootstrap script completes."))
parser.add_option("-c", None, action="store", dest="config_file",
                   help=("Specify the path to the buildout configuration "
                         "file to be used."))

options, args = parser.parse_args()

# if -c was provided, we push it back into args for buildout's main function
if options.config_file is not None:
    args += ['-c', options.config_file]

if options.eggs:
    eggs_dir = os.path.abspath(os.path.expanduser(options.eggs))
else:
    eggs_dir = tempfile.mkdtemp()

if options.setup_source is None:
    if options.use_distribute:
        options.setup_source = distribute_source
    else:
        options.setup_source = setuptools_source

args = args + ['bootstrap']


try:
    to_reload = False
    import pkg_resources
    to_reload = True
    if not hasattr(pkg_resources, '_distribute'):
        raise ImportError
    import setuptools  # A flag.  Sometimes pkg_resources is installed alone.
except ImportError:
    ez_code = urllib2.urlopen(
        options.setup_source).read().replace('\r\n', '\n')
    ez = {}
    exec ez_code in ez
    setup_args = dict(to_dir=eggs_dir, download_delay=0)
    if options.download_base:
        setup_args['download_base'] = options.download_base
    if options.use_distribute:
        setup_args['no_fake'] = True
    ez['use_setuptools'](**setup_args)
    if to_reload:
        reload(pkg_resources)
    else:
        import pkg_resources
    # This does not (always?) update the default working set.  We will
    # do it.
    for path in sys.path:
        if path not in pkg_resources.working_set.entries:
            pkg_resources.working_set.add_entry(path)

cmd = [quote(sys.executable),
       '-c',
       quote('from setuptools.command.easy_install import main; main()'),
       '-mqNxd',
       quote(eggs_dir)]

if options.download_base:
    cmd.extend(['-f', quote(options.download_base)])

requirement = 'zc.buildout'
if options.version:
    requirement = '=='.join((requirement, options.version))
cmd.append(requirement)

if options.use_distribute:
    setup_requirement = 'distribute'
else:
    setup_requirement = 'setuptools'
ws = pkg_resources.working_set
env = dict(
    os.environ,
    PYTHONPATH=ws.find(
        pkg_resources.Requirement.parse(setup_requirement)).location)

if is_jython:
    import subprocess
    exitcode = subprocess.Popen(cmd, env=env).wait()
else:  # Windows prefers this, apparently; otherwise we would prefer subprocess
    exitcode = os.spawnle(*([os.P_WAIT, sys.executable] + cmd + [env]))
if exitcode != 0:
    sys.stdout.flush()
    sys.stderr.flush()
    print ("An error occured when trying to install zc.buildout. "
           "Look above this message for any errors that "
           "were output by easy_install.")
    sys.exit(exitcode)

ws.add_entry(eggs_dir)
ws.require(requirement)
import zc.buildout.buildout
zc.buildout.buildout.main(args)
if not options.eggs:  # clean up temporary egg directory
    shutil.rmtree(eggs_dir)