build/android/gyp/generate_v14_compatible_resources.py

   1 #!/usr/bin/env python
   2 #
   3 # Copyright 2013 The Chromium Authors. All rights reserved.
   4 # Use of this source code is governed by a BSD-style license that can be
   5 # found in the LICENSE file.
   6
   7 """Convert Android xml resources to API 14 compatible.
   8
   9 There are two reasons that we cannot just use API 17 attributes,
  10 so we are generating another set of resources by this script.
  11
  12 1. paddingStart attribute can cause a crash on Galaxy Tab 2.
  13 2. There is a bug that paddingStart does not override paddingLeft on
  14    JB-MR1. This is fixed on JB-MR2. b/8654490
  15
  16 Therefore, this resource generation script can be removed when
  17 we drop the support for JB-MR1.
  18
  19 Please refer to http://crbug.com/235118 for the details.
  20 """
  21
  22 import codecs
  23 import optparse
  24 import os
  25 import re
  26 import shutil
  27 import sys
  28 import xml.dom.minidom as minidom
  29
  30 from util import build_utils
  31
  32 # Note that we are assuming 'android:' is an alias of
  33 # the namespace 'http://schemas.android.com/apk/res/android'.
  34
  35 GRAVITY_ATTRIBUTES = ('android:gravity', 'android:layout_gravity')
  36
  37 # Almost all the attributes that has "Start" or "End" in
  38 # its name should be mapped.
  39 ATTRIBUTES_TO_MAP = {'paddingStart' : 'paddingLeft',
  40                      'drawableStart' : 'drawableLeft',
  41                      'layout_alignStart' : 'layout_alignLeft',
  42                      'layout_marginStart' : 'layout_marginLeft',
  43                      'layout_alignParentStart' : 'layout_alignParentLeft',
  44                      'layout_toStartOf' : 'layout_toLeftOf',
  45                      'paddingEnd' : 'paddingRight',
  46                      'drawableEnd' : 'drawableRight',
  47                      'layout_alignEnd' : 'layout_alignRight',
  48                      'layout_marginEnd' : 'layout_marginRight',
  49                      'layout_alignParentEnd' : 'layout_alignParentRight',
  50                      'layout_toEndOf' : 'layout_toRightOf'}
  51
  52 ATTRIBUTES_TO_MAP = dict(['android:' + k, 'android:' + v] for k, v
  53                          in ATTRIBUTES_TO_MAP.iteritems())
  54
  55 ATTRIBUTES_TO_MAP_REVERSED = dict([v, k] for k, v
  56                                   in ATTRIBUTES_TO_MAP.iteritems())
  57
  58
  59 def IterateXmlElements(node):
  60   """minidom helper function that iterates all the element nodes.
  61   Iteration order is pre-order depth-first."""
  62   if node.nodeType == node.ELEMENT_NODE:
  63     yield node
  64   for child_node in node.childNodes:
  65     for child_node_element in IterateXmlElements(child_node):
  66       yield child_node_element
  67
  68
  69 def ParseAndReportErrors(filename):
  70   try:
  71     return minidom.parse(filename)
  72   except Exception: # pylint: disable=broad-except
  73     import traceback
  74     traceback.print_exc()
  75     sys.stderr.write('Failed to parse XML file: %s\n' % filename)
  76     sys.exit(1)
  77
  78
  79 def AssertNotDeprecatedAttribute(name, value, filename):
  80   """Raises an exception if the given attribute is deprecated."""
  81   msg = None
  82   if name in ATTRIBUTES_TO_MAP_REVERSED:
  83     msg = '{0} should use {1} instead of {2}'.format(filename,
  84         ATTRIBUTES_TO_MAP_REVERSED[name], name)
  85   elif name in GRAVITY_ATTRIBUTES and ('left' in value or 'right' in value):
  86     msg = '{0} should use start/end instead of left/right for {1}'.format(
  87         filename, name)
  88
  89   if msg:
  90     msg += ('\nFor background, see: http://android-developers.blogspot.com/'
  91             '2013/03/native-rtl-support-in-android-42.html\n'
  92             'If you have a legitimate need for this attribute, discuss with '
  93             'kkimlabs@chromium.org or newt@chromium.org')
  94     raise Exception(msg)
  95
  96
  97 def WriteDomToFile(dom, filename):
  98   """Write the given dom to filename."""
  99   build_utils.MakeDirectory(os.path.dirname(filename))
 100   with codecs.open(filename, 'w', 'utf-8') as f:
 101     dom.writexml(f, '', '  ', '\n', encoding='utf-8')
 102
 103
 104 def HasStyleResource(dom):
 105   """Return True if the dom is a style resource, False otherwise."""
 106   root_node = IterateXmlElements(dom).next()
 107   return bool(root_node.nodeName == 'resources' and
 108               list(root_node.getElementsByTagName('style')))
 109
 110
 111 def ErrorIfStyleResourceExistsInDir(input_dir):
 112   """If a style resource is in input_dir, raises an exception."""
 113   for input_filename in build_utils.FindInDirectory(input_dir, '*.xml'):
 114     dom = ParseAndReportErrors(input_filename)
 115     if HasStyleResource(dom):
 116       # Allow style file in third_party to exist in non-v17 directories so long
 117       # as they do not contain deprecated attributes.
 118       if not 'third_party' in input_dir or (
 119           GenerateV14StyleResourceDom(dom, input_filename)):
 120         raise Exception('error: style file ' + input_filename +
 121                         ' should be under ' + input_dir +
 122                         '-v17 directory. Please refer to '
 123                         'http://crbug.com/243952 for the details.')
 124
 125
 126 def GenerateV14LayoutResourceDom(dom, filename, assert_not_deprecated=True):
 127   """Convert layout resource to API 14 compatible layout resource.
 128
 129   Args:
 130     dom: Parsed minidom object to be modified.
 131     filename: Filename that the DOM was parsed from.
 132     assert_not_deprecated: Whether deprecated attributes (e.g. paddingLeft) will
 133                            cause an exception to be thrown.
 134
 135   Returns:
 136     True if dom is modified, False otherwise.
 137   """
 138   is_modified = False
 139
 140   # Iterate all the elements' attributes to find attributes to convert.
 141   for element in IterateXmlElements(dom):
 142     for name, value in list(element.attributes.items()):
 143       # Convert any API 17 Start/End attributes to Left/Right attributes.
 144       # For example, from paddingStart="10dp" to paddingLeft="10dp"
 145       # Note: gravity attributes are not necessary to convert because
 146       # start/end values are backward-compatible. Explained at
 147       # https://plus.sandbox.google.com/+RomanNurik/posts/huuJd8iVVXY?e=Showroom
 148       if name in ATTRIBUTES_TO_MAP:
 149         element.setAttribute(ATTRIBUTES_TO_MAP[name], value)
 150         del element.attributes[name]
 151         is_modified = True
 152       elif assert_not_deprecated:
 153         AssertNotDeprecatedAttribute(name, value, filename)
 154
 155   return is_modified
 156
 157
 158 def GenerateV14StyleResourceDom(dom, filename, assert_not_deprecated=True):
 159   """Convert style resource to API 14 compatible style resource.
 160
 161   Args:
 162     dom: Parsed minidom object to be modified.
 163     filename: Filename that the DOM was parsed from.
 164     assert_not_deprecated: Whether deprecated attributes (e.g. paddingLeft) will
 165                            cause an exception to be thrown.
 166
 167   Returns:
 168     True if dom is modified, False otherwise.
 169   """
 170   is_modified = False
 171
 172   for style_element in dom.getElementsByTagName('style'):
 173     for item_element in style_element.getElementsByTagName('item'):
 174       name = item_element.attributes['name'].value
 175       value = item_element.childNodes[0].nodeValue
 176       if name in ATTRIBUTES_TO_MAP:
 177         item_element.attributes['name'].value = ATTRIBUTES_TO_MAP[name]
 178         is_modified = True
 179       elif assert_not_deprecated:
 180         AssertNotDeprecatedAttribute(name, value, filename)
 181
 182   return is_modified
 183
 184
 185 def GenerateV14LayoutResource(input_filename, output_v14_filename,
 186                               output_v17_filename):
 187   """Convert API 17 layout resource to API 14 compatible layout resource.
 188
 189   It's mostly a simple replacement, s/Start/Left s/End/Right,
 190   on the attribute names.
 191   If the generated resource is identical to the original resource,
 192   don't do anything. If not, write the generated resource to
 193   output_v14_filename, and copy the original resource to output_v17_filename.
 194   """
 195   dom = ParseAndReportErrors(input_filename)
 196   is_modified = GenerateV14LayoutResourceDom(dom, input_filename)
 197
 198   if is_modified:
 199     # Write the generated resource.
 200     WriteDomToFile(dom, output_v14_filename)
 201
 202     # Copy the original resource.
 203     build_utils.MakeDirectory(os.path.dirname(output_v17_filename))
 204     shutil.copy2(input_filename, output_v17_filename)
 205
 206
 207 def GenerateV14StyleResource(input_filename, output_v14_filename):
 208   """Convert API 17 style resources to API 14 compatible style resource.
 209
 210   Write the generated style resource to output_v14_filename.
 211   It's mostly a simple replacement, s/Start/Left s/End/Right,
 212   on the attribute names.
 213   """
 214   dom = ParseAndReportErrors(input_filename)
 215   GenerateV14StyleResourceDom(dom, input_filename)
 216
 217   # Write the generated resource.
 218   WriteDomToFile(dom, output_v14_filename)
 219
 220
 221 def GenerateV14LayoutResourcesInDir(input_dir, output_v14_dir, output_v17_dir):
 222   """Convert layout resources to API 14 compatible resources in input_dir."""
 223   for input_filename in build_utils.FindInDirectory(input_dir, '*.xml'):
 224     rel_filename = os.path.relpath(input_filename, input_dir)
 225     output_v14_filename = os.path.join(output_v14_dir, rel_filename)
 226     output_v17_filename = os.path.join(output_v17_dir, rel_filename)
 227     GenerateV14LayoutResource(input_filename, output_v14_filename,
 228                               output_v17_filename)
 229
 230
 231 def GenerateV14StyleResourcesInDir(input_dir, output_v14_dir):
 232   """Convert style resources to API 14 compatible resources in input_dir."""
 233   for input_filename in build_utils.FindInDirectory(input_dir, '*.xml'):
 234     rel_filename = os.path.relpath(input_filename, input_dir)
 235     output_v14_filename = os.path.join(output_v14_dir, rel_filename)
 236     GenerateV14StyleResource(input_filename, output_v14_filename)
 237
 238
 239 def ParseArgs():
 240   """Parses command line options.
 241
 242   Returns:
 243     An options object as from optparse.OptionsParser.parse_args()
 244   """
 245   parser = optparse.OptionParser()
 246   parser.add_option('--res-dir',
 247                     help='directory containing resources '
 248                          'used to generate v14 compatible resources')
 249   parser.add_option('--res-v14-compatibility-dir',
 250                     help='output directory into which '
 251                          'v14 compatible resources will be generated')
 252   parser.add_option('--stamp', help='File to touch on success')
 253
 254   options, args = parser.parse_args()
 255
 256   if args:
 257     parser.error('No positional arguments should be given.')
 258
 259   # Check that required options have been provided.
 260   required_options = ('res_dir', 'res_v14_compatibility_dir')
 261   build_utils.CheckOptions(options, parser, required=required_options)
 262   return options
 263
 264 def GenerateV14Resources(res_dir, res_v14_dir):
 265   for name in os.listdir(res_dir):
 266     if not os.path.isdir(os.path.join(res_dir, name)):
 267       continue
 268
 269     dir_pieces = name.split('-')
 270     resource_type = dir_pieces[0]
 271     qualifiers = dir_pieces[1:]
 272
 273     api_level_qualifier_index = -1
 274     api_level_qualifier = ''
 275     for index, qualifier in enumerate(qualifiers):
 276       if re.match('v[0-9]+$', qualifier):
 277         api_level_qualifier_index = index
 278         api_level_qualifier = qualifier
 279         break
 280
 281     # Android pre-v17 API doesn't support RTL. Skip.
 282     if 'ldrtl' in qualifiers:
 283       continue
 284
 285     input_dir = os.path.abspath(os.path.join(res_dir, name))
 286
 287     # We also need to copy the original v17 resource to *-v17 directory
 288     # because the generated v14 resource will hide the original resource.
 289     output_v14_dir = os.path.join(res_v14_dir, name)
 290     output_v17_dir = os.path.join(res_v14_dir, name + '-v17')
 291
 292     # We only convert layout resources under layout*/, xml*/,
 293     # and style resources under values*/.
 294     if resource_type in ('layout', 'xml'):
 295       if not api_level_qualifier:
 296         GenerateV14LayoutResourcesInDir(input_dir, output_v14_dir,
 297                                         output_v17_dir)
 298     elif resource_type == 'values':
 299       if api_level_qualifier == 'v17':
 300         output_qualifiers = qualifiers[:]
 301         del output_qualifiers[api_level_qualifier_index]
 302         output_v14_dir = os.path.join(res_v14_dir,
 303                                       '-'.join([resource_type] +
 304                                                output_qualifiers))
 305         GenerateV14StyleResourcesInDir(input_dir, output_v14_dir)
 306       elif not api_level_qualifier:
 307         ErrorIfStyleResourceExistsInDir(input_dir)
 308
 309 def main():
 310   options = ParseArgs()
 311
 312   res_v14_dir = options.res_v14_compatibility_dir
 313
 314   build_utils.DeleteDirectory(res_v14_dir)
 315   build_utils.MakeDirectory(res_v14_dir)
 316
 317   GenerateV14Resources(options.res_dir, res_v14_dir)
 318
 319   if options.stamp:
 320     build_utils.Touch(options.stamp)
 321
 322 if __name__ == '__main__':
 323   sys.exit(main())
 324