[download_from_google_storage] Don't list ALL objects to check for ACLs

Currently check_bucket_permissions() in download_from_google_storage.py
performs a gsutil ls gs://bucket to determine whether the user has access
to the bucket or not.
This can be an EXTREMELY expensive operation (~minutes) if the bucket in
question has a lot of objects in the root (real case: chrome-telemetry).
It is worth noting that check_bucket_permissions() is not called just for
uploads but also for downloads, hence this is slowing down all invocations
of gclient sync on users and bots machine.
Removing the check_bucket_permissions() and let gsutil fail with an
Unauthorized error message if ACLs are not met.

BUG=458059

Review URL: https://codereview.chromium.org/923473002

git-svn-id: svn://svn.chromium.org/chrome/trunk/tools/depot_tools@294083 0039d316-1c4b-4281-b951-d872f2087c98

download_from_google_storage.py

@@ -105,18 +105,6 @@ class Gsutil(object):
     return (code, out, err)
 
 
-def check_bucket_permissions(base_url, gsutil):
-  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 code
-
-
 def check_platform(target):
   """Checks if any parent directory of target matches (win|mac|linux)."""
   assert os.path.isabs(target)
@@ -454,12 +442,6 @@ def main(args):
 
   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)
-    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,

upload_to_google_storage.py

@@ -15,7 +15,6 @@ import sys
 import threading
 import time
 
-from download_from_google_storage import check_bucket_permissions
 from download_from_google_storage import get_sha1
 from download_from_google_storage import Gsutil
 from download_from_google_storage import printer_worker
@@ -243,11 +242,6 @@ def main(args):
 
   base_url = 'gs://%s' % options.bucket
 
-  # Check we have a valid bucket with valid permissions.
-  code = check_bucket_permissions(base_url, gsutil)
-  if code:
-    return code
-
   return upload_to_google_storage(
       input_filenames, base_url, gsutil, options.force, options.use_md5,
       options.num_threads, options.skip_hashing)