wheels.py

#! /usr/bin/env python2
import os
import subprocess
import sys

from contextlib import contextmanager
from wheel.install import WheelFile
from wheel.util import matches_requirement


@contextmanager
def pushd(new_dir):
    current = os.getcwd()
    os.chdir(new_dir)
    try:
        yield
    finally:
        os.chdir(current)


def download(requirements, wheeldir):
    wheels = [WheelFile(f) for f in os.listdir(wheeldir)]
    with open(requirements, 'r') as f:
        reqs = [
            req.strip() for req in f
            if not req.startswith('-')
            and not matches_requirement(req, wheels)]

    if not reqs:
        print("Nothing to do.")
        return

    parent_pip = os.path.join(os.path.dirname(sys.executable), 'pip')
    pip = parent_pip if os.path.exists(parent_pip) else 'pip'

    cmd = '{0} wheel --wheel-dir={1}'.format(pip, wheeldir).split() + reqs

    try:
        out = subprocess.check_output(cmd)
    except subprocess.CalledProcessError as e:
        raise SystemExit(e.output)

    for line in out.split('\n'):
        if line.strip().startswith('Skipping building wheel'):
            url = line.split()[-1]

            url = url.split('#')[0]
            filename = url.rsplit('/')[-1]
            path = os.path.join(wheeldir, filename)
            if not os.path.exists(path):
                cmd = 'wget {0}'.format(url).split()
                with pushd(wheeldir):
                    out += subprocess.check_output(cmd)
    print(out)


if __name__ == '__main__':
    if len(sys.argv) != 3:
        raise SystemExit("Usage: python wheels.py <requirements> <wheel_dir>")
    download(sys.argv[1], sys.argv[2])