FileTypePolicies class to load types from proto.

chrome/browser/resources/safe_browsing/gen_file_type_proto.py

 #!/usr/bin/python
 # Copyright 2016 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.
 
 """
  Convert the ASCII download_file_types.asciipb proto into a binary resource.
 """
 
 import optparse
 import sys
 
 
 def ConvertProto(opts):
   # Find the proto code
   for path in opts.path:
     # Put the path to our proto libraries in front, so that we don't use system
     # protobuf.
     sys.path.insert(1, path)
 
   import download_file_types_pb2 as config_pb2
   import google.protobuf.text_format as text_format
 
   # Read the ASCII
-  ifile = open(opts.infile, 'r')
+  ifile = open(opts.infile, 'rb')

[Jialiu Lin, 2016/04/22 21:36:41]

should it be 'r', since you're not reading a binary proto?

[Nathan Parker, 2016/04/25 22:39:19]

Done.

   ascii_pb_str = ifile.read()
   ifile.close()
 
   # Parse it into a structure PB
   pb = config_pb2.DownloadFileTypeConfig()
   text_format.Merge(ascii_pb_str, pb)
 
   # Serialize it
   binary_pb_str = pb.SerializeToString()
 
   # Write it to disk
-  open(opts.outfile, 'w').write(binary_pb_str)
+  open(opts.outfile, 'wb').write(binary_pb_str)
 
 
 def main():
   parser = optparse.OptionParser()
   parser.add_option('-i', '--infile',
                     help='The ASCII DownloadFileType-proto file to read.')
   parser.add_option('-o', '--outfile',
                     help='The binary file to write.')
   parser.add_option('-p', '--path', action="append",
                     help='Repeat this as needed.  Directory(s) containing ' +
                     'the download_file_types_pb2.py and ' +
                     'google.protobuf.text_format modules')
   (opts, args) = parser.parse_args()
   if opts.infile is None or opts.outfile is None:
     parser.print_help()
     return 1
 
   try:
     ConvertProto(opts)
   except Exception as e:
     print "ERROR: %s failed to parse ASCII proto\n%s: %s\n" % (
         sys.argv, opts.infile, str(e))
     return 1
 
 if __name__ == '__main__':
   sys.exit(main())