check_server.py

#!/usr/bin/env python

# Simple server cleanup script for Debian.

# Author: Jorgen Schaefer <[email protected]>
# License: GPL

# Takes a list of wanted packages (comments with # allowed), marks
# everything else as automatically installed, uses apt-get autoremove
# to clean up the packages, and then checks whether any installed
# package versions are not even available from any currently
# configured sources.

import os
import subprocess
import sys


def main():
    if len(sys.argv) != 2:
        exit("usage: checksystem <packagelist.txt>")

    print("Marking unwanted packages as automatically installed")
    mark_auto(pkg for (pkg, ver) in get_installed_packages())
    mark_manual(get_wanted_packages(sys.argv[1]))
    print("Uninstalling superfluous packages")
    subprocess.check_call(["apt-get", "autoremove"])
    print("Checking available packages")
    available = get_available_packages()

    for pkg, ver in get_installed_packages():
        if pkg not in available:
            print("{0} version {1} installed, but not available"
                  .format(pkg, ver))
        elif ver not in available[pkg]:
            print("{0} version {1} installed, but only {2} available"
                  .format(pkg, ver, ", ".join(available[pkg])))

    print("All done")


def get_wanted_packages(pkgfile):
    with open(pkgfile) as f:
        for line in f:
            line = line.strip()
            if not line or line.startswith("#"):
                continue
            yield line


def get_available_packages():
    available = {}
    for filename in os.listdir("/var/lib/apt/lists/"):
        if filename.endswith("_Packages"):
            pkg = None
            ver = None
            with open(os.path.join("/var/lib/apt/lists/", filename)) as f:
                for line in f:
                    if line.startswith("Package:"):
                        _, pkg = line.strip().split(": ")
                    elif line.startswith("Version:"):
                        _, ver = line.strip().split(": ")
                    elif line.strip() == '':
                        if pkg is not None and ver is not None:
                            available.setdefault(pkg, set())
                            available[pkg].add(ver)
    return available


def get_installed_packages():
    p = subprocess.Popen(["dpkg", "-l"], stdout=subprocess.PIPE)
    stdout, stderr = p.communicate()
    for line in stdout.split("\n"):
        if line.startswith("ii"):
            cols = line.split()
            pkg = cols[1]
            ver = cols[2]
            yield pkg, ver


def mark_auto(packages):
    with open("/dev/null", "w") as devnull:
        subprocess.check_call(["apt-get", "markauto"] + list(packages),
                              stdout=devnull)


def mark_manual(packages):
    with open("/dev/null", "w") as devnull:
        subprocess.check_call(["apt-get", "unmarkauto"] + list(packages),
                              stdout=devnull)


if __name__ == '__main__':
    main()