sync_tgz.py

#!/usr/bin/python2.4
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"""Keep a local directory in sync with a website tar file.

This module downloads a tgz, and expands it as needed.
It supports username and password with basic authentication.
"""

import os
import shutil
import tarfile
import http_download


def SyncTgz(url, target, username=None, password=None, verbose=True):
  """Download a file from a remote server.

  Args:
    url: A URL to download from.
    target: Directory to extract to and prefix to use for tgz file.
    username: Optional username for download.
    password: Optional password for download (ignored if no username).
    verbose: Flag indicating if status shut be printed.
  """
  shutil.rmtree(target, True)
  tgz_filename = target + '.tgz'

  if verbose:
    print 'Downloading %s to %s...' % (url, tgz_filename)
  http_download.HttpDownload(url, tgz_filename,
                             username=username, password=password)

  if verbose:
    print 'Extracting from %s...' % tgz_filename
  tgz = tarfile.open(tgz_filename, 'r')
  for m in tgz:
    if verbose:
      print m.name
    tgz.extract(m, target)
  tgz.close()
  os.remove(tgz_filename)

  if verbose:
    print 'Update complete.'