python download Cassandra and start up in Windows

Description

This program will kill existing Cassandra before deploy new one.

Codes

import os
import shutil
import sys
import math
import urllib.request
import subprocess
import shlex
import signal
import time
import re
from datetime import date

def http_download(download_url, download_file):
    with urllib.request.urlopen(download_url) as f:
        with open(download_file,'wb') as target:
            filesize = int(f.getheader('Content-Length'))
            wrotesize = 0
            while True:
                if wrotesize == int(filesize):
                    break
                wrotesize += target.write(f.read(1024))
                download_percent = math.ceil((wrotesize/filesize)*100)
                print('\rDownload {0} to {1} ... {2}%'.format(download_url,download_file,download_percent),end='')
    print()

def find_pid_by_listen_port(port):
    if sys.platform == 'win32':
        output = subprocess.check_output('netstat -a -n -o', universal_newlines=True)
        match = re.search('.*:{0} +.* +.+ +[0-9]+'.format(port),output)
        if match:
            return shlex.split(match.group(0))[-1]
        else:
            return None
    else:
        raise Exception('not support platform ' + sys.platform)
    
    
download_url = 'http://ftp.tc.edu.tw/pub/Apache/cassandra/2.0.4/apache-cassandra-2.0.4-bin.tar.gz'
download_file = 'd:/apache-cassandra-2.0.4-bin.tar.gz'
unzip_folder = 'd:/deploy/work/{0}/apache-cassandra-2.0.4-bin'.format(date.today().isoformat())
execute_folder = unzip_folder + '/apache-cassandra-2.0.4'
execute_path = execute_folder + '/bin/cassandra.bat'
executable = 'start cmd /c ' + execute_path
executable_argv = shlex.split(executable)
pid = find_pid_by_listen_port(9160)
if pid:
    print('kill process id',pid)
    os.kill(int(pid),signal.SIGTERM)
if os.path.exists('d:/deploy'):
    print('Delete d:/deploy')
    shutil.rmtree('d:/deploy')
http_download(download_url, download_file)
os.makedirs(unzip_folder)
print('unzip {0} to {1}'.format(download_file, unzip_folder))
shutil.unpack_archive(download_file, unzip_folder)
print('Execute',execute_path)
subprocess.Popen(executable_argv,shell=True)