Adds --config option to download_from_google_storage.py

download_from_google_storage.py

 #!/usr/bin/env python
 # Copyright (c) 2012 The Chromium Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
 """Download files from Google Storage based on SHA1 sums."""
 
 
 import hashlib
 import optparse
@@ skipping 64 matching lines @@
 
 def check_bucket_permissions(bucket, gsutil):
   if not bucket:
     print >> sys.stderr, 'Missing bucket %s.'
     return (None, 1)
   base_url = 'gs://%s' % bucket
 
   code, _, ls_err = gsutil.check_call('ls', base_url)
   if code == 403:
     print >> sys.stderr, 'Got error 403 while authenticating to %s.' % base_url
-    print >> sys.stderr, 'Try running "gsutil config".'
+    print >> sys.stderr, 'Try running "download_from_google_storage --config".'
   elif code == 404:
     print >> sys.stderr, '%s not found.' % base_url
   elif code != 0:
     print >> sys.stderr, ls_err
   return (base_url, code)
 
 
 def get_sha1(filename):
   sha1 = hashlib.sha1()
   with open(filename, 'rb') as f:
@@ skipping 169 matching lines @@
                     help='Scan folders recursively for .sha1 files. '
                          'Must be used with -d/--directory')
   parser.add_option('-t', '--num_threads', default=1, type='int',
                     help='Number of downloader threads to run.')
   parser.add_option('-d', '--directory', action='store_true',
                     help='The target is a directory.  '
                          'Cannot be used with -s/--sha1_file.')
   parser.add_option('-s', '--sha1_file', action='store_true',
                     help='The target is a file containing a sha1 sum.  '
                          'Cannot be used with -d/--directory.')
+  parser.add_option('-g', '--config', action='store_true',
+                    help='Alias for "gsutil config".  Run this if you want '
+                         'to initialize your saved Google Storage '
+                         'credentials.')
 
   (options, args) = parser.parse_args()
+  # First, make sure we can find a working instance of gsutil.
+  if os.path.exists(GSUTIL_DEFAULT_PATH):
+    gsutil = Gsutil(GSUTIL_DEFAULT_PATH, boto_path=options.boto)
+  else:
+    gsutil = None
+    for path in os.environ["PATH"].split(os.pathsep):
+      if os.path.exists(path) and 'gsutil' in os.listdir(path):
+        gsutil = Gsutil(os.path.join(path, 'gsutil'), boto_path=options.boto)

[M-A Ruel, 2013/07/09 15:20:19]

Add a "break" statement after, no need to continue searching.

You could also use for/else instead, removing the need for line 285. E.g.
for path in os.environ["PATH"].split(os.pathsep):
  if os.path.exists(path) and 'gsutil' in os.listdir(path):
    gsutil = Gsutil(os.path.join(path, 'gsutil'), boto_path=options.boto)
    break
else:
  parser.error(...)

+    if not gsutil:
+      parser.error('gsutil not found in %s, bad depot_tools checkout?' %
+                  GSUTIL_DEFAULT_PATH)
+
+  # Passing in -g/--config will run our copy of GSUtil, then quit.
+  if options.config:
+    return gsutil.call('config')
+
   if not args:
     parser.error('Missing target.')
   if len(args) > 1:
     parser.error('Too many targets.')
   if not options.bucket:
     parser.error('Missing bucket.  Specify bucket with --bucket.')
   if options.sha1_file and options.directory:
     parser.error('Both --directory and --sha1_file are specified, '
                  'can only specify one.')
   if options.recursive and not options.directory:
@@ skipping 17 matching lines @@
       options.output = input_filename[:-5]
     else:
       parser.error('Unreachable state.')
 
   # Check if output file already exists.
   if not options.directory and not options.force and not options.no_resume:
     if os.path.exists(options.output):
       parser.error('Output file %s exists and --no_resume is specified.'
                    % options.output)
 
-  # Make sure we can find a working instance of gsutil.
-  if os.path.exists(GSUTIL_DEFAULT_PATH):
-    gsutil = Gsutil(GSUTIL_DEFAULT_PATH, boto_path=options.boto)
-  else:
-    gsutil = None
-    for path in os.environ["PATH"].split(os.pathsep):
-      if os.path.exists(path) and 'gsutil' in os.listdir(path):
-        gsutil = Gsutil(os.path.join(path, 'gsutil'), boto_path=options.boto)
-    if not gsutil:
-      parser.error('gsutil not found in %s, bad depot_tools checkout?' %
-                   GSUTIL_DEFAULT_PATH)
-
   # Check we have a valid bucket with valid permissions.
   base_url, code = check_bucket_permissions(options.bucket, gsutil)
   if code:
     return code
 
   return download_from_google_storage(
       input_filename, base_url, gsutil, options.num_threads, options.directory,
       options.recursive, options.force, options.output, options.ignore_errors,
       options.sha1_file)
 
 
 if __name__ == '__main__':
   sys.exit(main(sys.argv))