tools/grit/grit/format/chrome_messages_json.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.

"""Formats as a .json file that can be used to localize Google Chrome
extensions."""

from json import JSONEncoder
import re
import types

from grit import util
from grit.node import message

def Format(root, lang='en', output_dir='.'):
  """Format the messages as JSON."""
  yield '{\n'

  encoder = JSONEncoder();
  format = ('  "%s": {\n'
            '    "message": %s%s\n'
            '  }')
  placeholder_format = ('      "%i": {\n'
                        '        "content": "$%i"\n'
                        '      }')
  first = True
  for child in root.ActiveDescendants():
    if isinstance(child, message.MessageNode):
      id = child.attrs['name']
      if id.startswith('IDR_') or id.startswith('IDS_'):
        id = id[4:]

      loc_message = encoder.encode(child.ws_at_start + child.Translate(lang) +
                                   child.ws_at_end)

      # Replace $n place-holders with $n$ and add an appropriate "placeholders"
      # entry. Note that chrome.i18n.getMessage only supports 9 placeholders:
      # https://developer.chrome.com/extensions/i18n#method-getMessage
      placeholders = ''
      for i in range(1, 10):
        if loc_message.find('$%d' % i) == -1:
          break
        loc_message = loc_message.replace('$%d' % i, '$%d$' % i)
        if placeholders:
          placeholders += ',\n'
        placeholders += placeholder_format % (i, i)

      if not first:
        yield ',\n'
      first = False

      if placeholders:
        placeholders = ',\n    "placeholders": {\n%s\n    }' % placeholders
      yield format % (id, loc_message, placeholders)

  yield '\n}\n'