movescript.py

#! /usr/bin/env python

import sys, string

def analyze_log(path):
    logfile = open(path,"r")
    cont = logfile.readlines()
    logfile.close()
    cont = parse_log(cont)
    toinstall = {}
    while cont:
        endpos = cont.index("End")
        cut = cont[1:endpos]
        toinstall[cont[0]] = cut
        del cont[:endpos+1]
    toinstall = dict([(key, toinstall[key]) for key in toinstall if toinstall[key]])
    return toinstall
        
def parse_log(cont):
    cont_new = []
    for x in cont:
        if x[:5] == "Start":
            cont_new.append(string.strip(x))
        elif x[:3] == "End":
            cont_new.append("End")
        elif x[:7] == "Install":
            progs = string.split(x," ")
            for prog in progs:
                if prog != "Install:" and prog[0] != '(' and prog[0] not in '0123456789':
                    cont_new.append(prog)
        elif x[:7] == "Upgrade":
            pass
        elif x[:6] == "Remove" or x[:5] == "Purge":
            progs = string.split(x," ")
            for prog in progs:
                while cont_new.count(prog):
                    cont_new.remove(prog)
    return cont_new

def create_script(path,progs):
    script = open(path,"w")
    script.write("#! /bin/bash\n\n")
    script.write("# autocreated installation file with movescript.py\n")
    script.write("# comment files you don't want to install with sharp\n\n")
    for key in progs:
        script.write("# "+key+"\n")
        script.write("apt-get install "+string.join(progs[key],' ')+"\n")
    script.close()

def main(args):
    log = "/var/log/apt/history.log"
    if len(args) == 1:
        log = args[1]
        out = args[2]
    else:
        out = args[1]
    progs = analyze_log(log)
    create_script(out,progs)
    #print "Script created!"

if __name__ == "__main__":
    if len(sys.argv) == 1:
        print "run as 'python movescript.py [infile] outfile'"
    else: main(sys.argv)

Use this script on debian based systems for backuping installed programs for e. g. system reinstalling etc. This script analyzes logfile of apt and creates output script that installs same programs that are in log.

So it is similar to pacman -Qqe on Arch Linux.