Simple tool to automate decompilation of war files using Procyon

procyon-war-wrapper.py

#!/usr/bin/python3

import os
import sys
import uuid

from shutil import rmtree
from subprocess import Popen, PIPE

def usage(program):
    print("It's a simple tool to automate decompilation of war files using Procyon.")
    print(f'Usage:\n python {program} <path/procyon.jar> <path/app.war> <path/output/dir>')
    print(f'Example:\n python {program} ~/Downloads/procyon-decompiler-0.5.36.jar ~/Downloads/library-x.war ~/Downloads/output')
    exit()

def execute(command):
    decompiler = Popen(command, shell=False, stdout=PIPE, stderr=PIPE)
    o, e = decompiler.communicate()
    e = e.decode('utf8')
    o = o.decode('utf8')

    print(o)
    print(e)

def main():
    program = sys.argv[0]

    if len(sys.argv) != 4:
        usage(program)

    procyon_path = sys.argv[1]
    war_path = sys.argv[2]
    output_dir = sys.argv[3]

    if not os.path.isfile(procyon_path) or procyon_path[-4:] != '.jar':
        print(f'[-] Provided procyon path ({procyon_path}) is incorrect')
        usage(program)

    if os.path.isdir(war_path):
        print(f'[-] Provided path to a war file ({war_path}) is a directory')
        usage(program)
    elif not os.path.isfile(war_path):
        print(f'[-] Provided war file ({war_path}) does not exist')
        usage(program)

    if os.path.isfile(output_dir):
        print(f'[-] Provided path to output directory ({output_dir}) is a file')
        usage(program)
    elif not os.path.exists(output_dir):
        print(f'[*] Provided path to output directory ({output_dir}) does not exist. Creating...')
        os.mkdir(output_dir)

    classes = []

    war_dir = str(uuid.uuid4())
    print(war_dir)
    cmd = ['unzip', '-d', war_dir, war_path]
    execute(cmd)

    for (root, dirs, files) in os.walk(war_dir, topdown=True):
        for file in files:
            if file[-6:] == '.class':
                classes.append(f'{root}/{file}')

    cmd = ['java', '-jar', procyon_path, '-o', output_dir]
    cmd.extend(classes)

    execute(cmd)
    rmtree(war_dir)

if __name__ == '__main__':
    main()