Download all available versions of aws 'opsworks-agent-installer.tgz' for examination

opsworks-agent-downloader.py

#!/usr/bin/env python

import os, time, urllib2, shutil, urlparse

def main():
    for version in range(450):
        try:
            url = 'https://opsworks-instance-agent.s3.amazonaws.com:443/%d/opsworks-agent-installer.tgz' % version
            filename = 'opsworks-agent-installer-%03d.tgz' % version
            download(url, filename)
            print('version %d successfully downloaded' % version)
        except urllib2.HTTPError, e:
            print('version %d does not exist' % version)

def download(url, fileName=None):
    def getFileName(url,openUrl):
        filename = None
        if 'Content-Disposition' in openUrl.info():
            cd = dict(map(
                lambda x: x.strip().split('=') if '=' in x else (x.strip(),''),
                openUrl.info()['Content-Disposition'].split(';')))
            if 'filename' in cd:
                filename = cd['filename'].strip("\"'")
        return filename or os.path.basename(urlparse.urlsplit(openUrl.url)[2])

    def getLastModified(url,openUrl):
        mTime = None
        if 'Last-Modified' in openUrl.info():
            lmStr = openUrl.info()['Last-Modified']
            mTime = time.mktime(time.strptime(lmStr, "%a, %d %b %Y %H:%M:%S GMT"))
        return mTime or time.time()

    r = urllib2.urlopen(urllib2.Request(url))
    try:
        fileName = fileName or getFileName(url,r)
        lastModified = getLastModified(url,r)
        with open(fileName, 'wb') as f:
            shutil.copyfileobj(r,f)
        os.utime(fileName, (lastModified, lastModified))
    finally:
        r.close()

if __name__ == "__main__":
    try:
        main()
    except KeyboardInterrupt:
        print "\nOpteration Aborted\n"