Revert of Don't check bucket permissions if --no-auth.

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 92 matching lines @@
     if status_code_match:
       return (int(status_code_match.group(1)), out, err)
     if ('You are attempting to access protected data with '
           'no configured credentials.' in err):
       return (403, out, err)
     if 'No such object' in err:
       return (404, out, err)
     return (code, out, err)
 
 
-def check_bucket_permissions(base_url, gsutil):
+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 != 0:
     print >> sys.stderr, ls_err
   if code == 403:
     print >> sys.stderr, 'Got error 403 while authenticating to %s.' % base_url
     print >> sys.stderr, 'Try running "download_from_google_storage --config".'
   elif code == 404:
     print >> sys.stderr, '%s not found.' % base_url
   return (base_url, code)
 
@@ skipping 321 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)
 
-  base_url = 'gs://%s' % options.bucket
-
   # Check we have a valid bucket with valid permissions.
-  if not options.no_auth:
-    code = check_bucket_permissions(base_url, gsutil, options.no_auth)
-    if code:
-      return code
+  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, options.verbose, options.auto_platform)
 
 
 if __name__ == '__main__':
   sys.exit(main(sys.argv))