Move helper functions into a common module.

script/lib/util.py

@@ -0,0 +1,53 @@
+import atexit
+import shutil
+import tarfile
+import tempfile
+import urllib2
+
+
+def download(text, url, filename):
+  directory = tempfile.mkdtemp(prefix='atom-shell-')
+  atexit.register(shutil.rmtree, directory)
+
+  web_file = urllib2.urlopen(url)
+  file_size = int(web_file.info().getheaders("Content-Length")[0])
+  downloaded_size = 0
+  block_size = 128
+
+  with open(os.path.join(directory, filename), 'w+') as local_file:
+    while True:
+      buf = web_file.read(block_size)
+      if not buf:
+        break
+
+      downloaded_size += len(buf)
+      local_file.write(buf)
+
+      percent = downloaded_size * 100. / file_size
+      status = "\r%s  %10d  [%3.1f%%]" % (text, downloaded_size, percent)
+      print status,
+
+    print
+
+  return directory
+
+
+def extract_tarball(tarball_path, member, path):
+  with tarfile.open(tarball_path) as tarball:
+    tarball.extract(member, path)
+
+
+def safe_unlink(path):
+  try:
+    os.unlink(path)
+  except OSError as e:
+    if e.errno != errno.ENOENT:
+      raise
+
+
+def safe_mkdir(path):
+  try:
+    os.makedirs(path)
+  except OSError as e:
+    if e.errno != errno.EEXIST:
+      raise