A script to build wheels from existing PyPI distributions using distlib and vanilla pip. Not usable with distributions you already have installed. Builds dependent wheels by default, though you can turn that off with --no-deps.

wheeler.py

#!/usr/bin/env python
# -*- coding: utf-8 -*-
#
# Copyright (C) 2013-2016 Vinay Sajip. License: MIT
#

import logging
import optparse     # for 2.6
import os
import re
import shutil
import subprocess
import sys
import tempfile

logger = logging.getLogger('wheeler')

from distlib.compat import configparser, filter
from distlib.database import DistributionPath, Distribution, make_graph
from distlib.locators import (JSONLocator, SimpleScrapingLocator,
                              AggregatingLocator, DependencyFinder)
from distlib.manifest import Manifest
from distlib.metadata import Metadata
from distlib.util import parse_requirement, get_package_data
from distlib.wheel import Wheel

EGG_INFO_RE = re.compile(r'(-py\d\.\d)?\.egg-info', re.I)

INSTALLED_DISTS = DistributionPath(include_egg=True)


def get_requirements(data):
    lines = []
    for line in data.splitlines():
        line = line.strip()
        if not line or line[0] == '#':
            continue
        lines.append(line)
    reqts = []
    extras = {}
    result = {'install': reqts, 'extras': extras}
    for line in lines:
        if line[0] != '[':
            reqts.append(line)
        else:
            i = line.find(']', 1)
            if i < 0:
                raise ValueError('unrecognised line: %r' % line)
            extra = line[1:i]
            extras[extra] = reqts = []
    return result


def convert_egg_info(libdir, prefix, options):
    files = os.listdir(libdir)
    ei = list(filter(lambda d: d.endswith('.egg-info'), files))[0]
    olddn = os.path.join(libdir, ei)
    di = EGG_INFO_RE.sub('.dist-info', ei)
    newdn = os.path.join(libdir, di)
    os.rename(olddn, newdn)
    if options.compatible:
        renames = {}
    else:
        renames = {
            'entry_points.txt': 'EXPORTS',
        }
    excludes = set([
        'SOURCES.txt',          # of no interest in/post WHEEL
        'installed-files.txt',  # replaced by RECORD, so not needed
        'requires.txt',         # added to METADATA, so not needed
        'PKG-INFO',             # replaced by METADATA
        'not-zip-safe',         # not applicable
    ])
    files = os.listdir(newdn)
    metadata = mdname = reqts = None
    for oldfn in files:
        pn = os.path.join(newdn, oldfn)
        if oldfn in renames:
            os.rename(pn, os.path.join(newdn, renames[oldfn]))
        else:
            if oldfn == 'requires.txt':
                with open(pn, 'r') as f:
                    reqts = get_requirements(f.read())
            elif oldfn == 'PKG-INFO':
                metadata = Metadata(path=pn)
                pd = get_package_data(metadata.name, metadata.version)
                metadata = Metadata(mapping=pd['index-metadata'])
                mdname = os.path.join(newdn, 'pydist.json')
            if oldfn in excludes or not options.compatible:
                os.remove(pn)
    if metadata:
        # Use Metadata 1.2 or later
        metadata.provides += ['%s (%s)' % (metadata.name,
                                           metadata.version)]
        # Update if not set up by get_package_data
        if reqts and not metadata.run_requires:
            metadata.dependencies = reqts
        metadata.write(path=mdname)
    manifest = Manifest(os.path.dirname(libdir))
    manifest.findall()
    paths = manifest.allfiles
    dp = DistributionPath([libdir])
    dist = next(dp.get_distributions())
    dist.write_installed_files(paths, prefix)


def install_dist(distname, workdir, options):
    pfx = '--install-option='
    purelib = pfx + '--install-purelib=%s/purelib' % workdir
    platlib = pfx + '--install-platlib=%s/platlib' % workdir
    headers = pfx + '--install-headers=%s/headers' % workdir
    scripts = pfx + '--install-scripts=%s/scripts' % workdir
    data = pfx + '--install-data=%s/data' % workdir
    # Use the pip adjacent to sys.executable, if any (for virtualenvs)
    d = os.path.dirname(sys.executable)
    files = filter(lambda o: o in ('pip', 'pip.exe'), os.listdir(d))
    if not files:
        prog = 'pip'
    else:
        prog = os.path.join(d, next(files))
    cmd = [prog, 'install',
           '--no-deps', '--quiet',
           '--index-url', 'https://pypi.python.org/simple/',
           '--timeout', '3', '--default-timeout', '3',
           purelib, platlib, headers, scripts, data, distname]
    result = {
        'scripts': os.path.join(workdir, 'scripts'),
        'headers': os.path.join(workdir, 'headers'),
        'data': os.path.join(workdir, 'data'),
    }
    print('Pipping %s ...' % distname)
    p = subprocess.Popen(cmd, shell=False, stdout=sys.stdout,
                         stderr=subprocess.STDOUT)
    stdout, _ = p.communicate()
    if p.returncode:
        raise ValueError('pip failed to install %s:\n%s' % (distname, stdout))
    for dn in ('purelib', 'platlib'):
        libdir = os.path.join(workdir, dn)
        if os.path.isdir(libdir):
            result[dn] = libdir
            break
    convert_egg_info(libdir, workdir, options)
    dp = DistributionPath([libdir])
    dist = next(dp.get_distributions())
    md = dist.metadata
    result['name'] = md.name
    result['version'] = md.version
    return result


def build_wheel(distname, options):
    result = None
    r = parse_requirement(distname)
    if not r:
        print('Invalid requirement: %r' % distname)
    else:
        dist = INSTALLED_DISTS.get_distribution(r.name)
        if dist:
            print('Can\'t build a wheel from already-installed '
                  'distribution %s' % dist.name_and_version)
        else:
            workdir = tempfile.mkdtemp()    # where the Wheel input files will live
            try:
                paths = install_dist(distname, workdir, options)
                paths['prefix'] = workdir
                wheel = Wheel()
                wheel.name = paths.pop('name')
                wheel.version = paths.pop('version')
                wheel.dirname = options.destdir
                wheel.build(paths)
                result = wheel
            finally:
                shutil.rmtree(workdir)
    return result


def main(args=None):
    parser = optparse.OptionParser(usage='%prog [options] requirement [requirement ...]')
    parser.add_option('-d', '--dest', dest='destdir', metavar='DESTDIR',
                      default=os.getcwd(), help='Where you want the wheels '
                      'to be put.')
    parser.add_option('-n', '--no-deps', dest='deps', default=True,
                      action='store_false',
                      help='Don\'t build dependent wheels.')
    options, args = parser.parse_args(args)
    options.compatible = True   # may add flag to turn off later
    if not args:
        parser.print_usage()
    else:
        # Check if pip is available; no point in continuing, otherwise
        try:
            with open(os.devnull, 'w') as f:
                p = subprocess.call(['pip', '--version'], stdout=f, stderr=subprocess.STDOUT)
        except Exception:
            p = 1
        if p:
            print('pip appears not to be available. Wheeler needs pip to '
                  'build  wheels.')
            return 1
        if options.deps:
            # collect all the requirements, including dependencies
            u = 'http://pypi.python.org/simple/'
            locator = AggregatingLocator(JSONLocator(),
                                         SimpleScrapingLocator(u, timeout=3.0),
                                         scheme='legacy')
            finder = DependencyFinder(locator)
            wanted = set()
            for arg in args:
                r = parse_requirement(arg)
                if not r.constraints:
                    dname = r.name
                else:
                    dname = '%s (%s)' % (r.name, ', '.join(r.constraints))
                print('Finding the dependencies of %s ...' % arg)
                dists, problems = finder.find(dname)
                if problems:
                    print('There were some problems resolving dependencies '
                          'for %r.' % arg)
                    for _, info in problems:
                        print('  Unsatisfied requirement %r' % info)
                wanted |= dists
            want_ordered = True     # set to False to skip ordering
            if not want_ordered:
                wanted = list(wanted)
            else:
                graph = make_graph(wanted, scheme=locator.scheme)
                slist, cycle = graph.topological_sort()
                if cycle:
                    # Now sort the remainder on dependency count.
                    cycle = sorted(cycle, reverse=True,
                                   key=lambda d: len(graph.reverse_list[d]))
                wanted = slist + cycle

                # get rid of any installed distributions from the list
                for w in list(wanted):
                    dist = INSTALLED_DISTS.get_distribution(w.name)
                    if dist or w.name in ('setuptools', 'distribute'):
                        wanted.remove(w)
                        s = w.name_and_version
                        print('Skipped already-installed distribution %s' % s)

            # converted wanted list to pip-style requirements
            args = ['%s==%s' % (dist.name, dist.version) for dist in wanted]

        # Now go build
        built = []
        for arg in args:
            wheel = build_wheel(arg, options)
            if wheel:
                built.append(wheel)
        if built:
            if options.destdir == os.getcwd():
                dest = ''
            else:
                dest = ' in %s' % options.destdir
            print('The following wheels were built%s:' % dest)
            for wheel in built:
                print('  %s' % wheel.filename)

if __name__ == '__main__':
    logging.basicConfig(format='%(levelname)-8s %(name)s %(message)s',
                        filename='wheeler.log', filemode='w')
    try:
        rc = main()
    except Exception as e:
        print('Failed - sorry! Reason: %s\nPlease check the log.' % e)
        logger.exception('Failed.')
        rc = 1
    sys.exit(rc)

Updated 04 Mar 2013 09:35 Now writes 1.2 metadata, reads requires.txt to update dependencies, prints error message on exception rather than just dying silently.

Updated 05 Mar 2013 11:38 to leave setuptools files in .dist-info unless specifically known to be inappropriate to leave in place.

Updated 05 Mar 2013 12:49 to improve requires.txt handling.

Updated 08 Mar 2013 00:13 to improve metadata written.

Updated 17 Feb 2016 18:11 to use https for PyPI and pydist.json for the name of the metadata file.