find-deps.py

import os
import subprocess

base = [f.rsplit('-', 3)[0] for f in os.listdir('..') if f.endswith('.xz')]

downloaded = {'sh'}


def clean(p):
    return p.split('>=')[0].split('=')[0]


def deps(pkg):
    if pkg == 'awk':
        pkg = 'gawk'
    out = subprocess.check_output(
        'pacman -Si "{0}"|grep "Depends On"'.format(pkg),
        shell=True,
    )
    return [clean(p) for p in
            out[len('Depends On     : '):].decode().strip().split()
            if p not in ['None', 'libncursesw.so=6-64']]


def provides(pkg):
    if pkg == 'awk':
        pkg = 'gawk'
    out = subprocess.check_output(
        'pacman -Si "{0}"|grep "Provides       :"'.format(pkg),
        shell=True,
    )
    return [clean(p) for p in out[len("Provides       : "):].decode().strip().split()
            if p not in ['None']]


def download(dep):
    link = subprocess.check_output('pacman -Sp {0}'.format(dep),
                                   shell=True).decode().strip()
    path = link.rsplit(os.sep)[-1]
    if not os.path.exists(path):
        print("downloading {0}".format(dep))
        subprocess.check_output('wget {0}'.format(link), shell=True)


def resolve(pkg):
    if pkg in downloaded:
        return

    print("resolving {0}".format(pkg))

    dependencies = deps(pkg)
    for dep in dependencies:
        resolve(dep)
        download(dep)
    downloaded.add(pkg)
    for provided in provides(pkg):
        downloaded.add(provided)

for pkg in base:
    resolve(pkg)