[Android] Auto-generate API 14 resources from the existing API 17 resources.

build/android/gyp/generate_v14_resources.py

Index: build/android/gyp/generate_v14_resources.py
diff --git a/build/android/gyp/generate_v14_resources.py b/build/android/gyp/generate_v14_resources.py
new file mode 100755
index 0000000000000000000000000000000000000000..d20d34aabd6c7241934447b52ab690fe87402b23
--- /dev/null
+++ b/build/android/gyp/generate_v14_resources.py
@@ -0,0 +1,171 @@
+#!/usr/bin/env python
+#
+# Copyright 2013 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.
+
+import optparse
+import os
+import re
+import sys
+import xml.etree.cElementTree as ET
+import xml.dom.minidom as minidom
+
+from util import build_utils
+
+
+ATTRIBUTE_NAMESPACE = u'http://schemas.android.com/apk/res/android'
+
+# The list of the attributes were taken from go/android-rtl
+ATTRIBUTES_TO_MAP = {'paddingStart' : 'paddingLeft',
+                     'drawableStart' : 'drawableLeft',
+                     'layout_alignStart' : 'layout_alignLeft',
+                     'layout_marginStart' : 'layout_marginLeft',
+                     'layout_alignParentStart' : 'layout_alignParentLeft',
+                     'layout_toStartOf' : 'layout_toLeftOf',
+                     'paddingEnd' : 'paddingRight',
+                     'drawableEnd' : 'drawableRight',
+                     'layout_alignEnd' : 'layout_alignRight',
+                     'layout_marginEnd' : 'layout_marginRight',
+                     'layout_alignParentEnd' : 'layout_alignParentRight',
+                     'layout_toEndOf' : 'layout_toRightOf'}
+
+ATTRIBUTES_TO_MAP = {(ATTRIBUTE_NAMESPACE,  k) : (ATTRIBUTE_NAMESPACE , v)
+                    for k, v in ATTRIBUTES_TO_MAP.items()}
+
+GRAVITY_ATTRIBUTES = ('gravity', 'layout_gravity')
+
+GRAVITY_ATTRIBUTES = [(ATTRIBUTE_NAMESPACE, i) for i in GRAVITY_ATTRIBUTES]
+
+
+def iterate_xml_elements(node):
+  """minidom helper function that iterates all the element nodes. Depth-first.
+  """
+  if node.nodeType == node.ELEMENT_NODE:
+    yield node
+  for child_node in node.childNodes:
+    for child_node_element in iterate_xml_elements(child_node):
+      yield child_node_element
+
+
+def generate_pre_v17_resource(input_filename, output_filename):
+  """Convert resource to API 14 compatible resource.
+
+  It's mostly a simple replacement, s/Start/Left s/End/Right,
+  on the attribute names.
+  """
+  dom = minidom.parse(input_filename)
+
+  for element in iterate_xml_elements(dom):
+    all_names = element.attributes.keysNS()
+
+    # Iterate all the attributes to find attributes to convert.
+    # Note that name variable is actually a tuple that has namespace and name.
+    # For example,
+    # name == ('http://schemas.android.com/apk/res/android', 'paddingStart')
+    for name, value in list(element.attributes.itemsNS()):
+      # For gravity attributes, replace start/end to left/right.
+      # For example, gravity="start" to gravity="end"
+      # This is actually not necessary because start/end is backward-compatible.
+      if name in GRAVITY_ATTRIBUTES:
+        replaced_value = re.sub('start|end',
+            lambda x: 'left' if x.group(0) == 'start' else 'right', value)
+        element.setAttributeNS(name[0], name[1], replaced_value)
+      # Convert any other API 17 Start/End attributes to Left/Right attributes.
+      # For example, from paddingStart="10dp" to paddingLeft="10dp"
+      elif name in ATTRIBUTES_TO_MAP.keys():
+        mapped_name = ATTRIBUTES_TO_MAP[name]
+
+        # If, for example, paddingLeft and paddingStart are used
+        # but have different values, then it is definitely not right.
+        if mapped_name in all_names:
+          if value != element.getAttributeNS(*mapped_name):
+            error_message = '[ERROR]' + input_filename + '\n'
+            error_message += ('These Attributes are defined'
+                             'but the values are different.\n')
+            error_message += name[1] + ' = '
+            error_message += element.getAttributeNS(*name) + '\n'
+            error_message += mapped_name[1] + ' = '
+            error_message += element.getAttributeNS(*mapped_name) + '\n'
+            print >> sys.stderr, error_message
+            sys.exit(1)
+
+        # Add the new mapped attribute and remove the original attribute.
+        # For example, add paddingLeft and remove paddingStart.
+        element.setAttributeNS(mapped_name[0], mapped_name[1], value)
+        del element.attributes[name]
+
+  build_utils.MakeDirectory(os.path.dirname(output_filename))
+  dom.writexml(open(output_filename,"w"), '  ', '\n')
+
+
+def generate_v14_resources_in_dir(input_dir, output_dir):
+  """Convert resources to API 14 compatible resources in the directory
+  recursively.
+  """
+  for root, dirs, files in os.walk(input_dir, followlinks=True):
+    relative_dir = os.path.relpath(root, input_dir)
+    for file_name in files:
+      if file_name.lower().endswith('.xml'):
+        input_filename = os.path.join(input_dir, relative_dir, file_name)
+        output_filename = os.path.join(output_dir, relative_dir, file_name)
+        generate_pre_v17_resource(input_filename, output_filename)
+
+
+def ParseArgs():
+  """Parses command line options.
+
+  Returns:
+    An options object as from optparse.OptionsParser.parse_args()
+  """
+  parser = optparse.OptionParser()
+  parser.add_option('--res-dir',
+                    help='directory containing v17 resources '
+                         'be used to generate v14 resources')
+  parser.add_option('--res-v14-dir',
+                    help='directory containing v14 resources to be generated')
+
+  (options, args) = parser.parse_args()
+
+  if args:
+    parser.error('No positional arguments should be given.')
+
+  # Check that required options have been provided.
+  required_options = ('res_dir', 'res_v14_dir')
+  build_utils.CheckOptions(options, parser, required=required_options)
+  return options
+
+
+def main(argv):
+  """Convert Android xml resources to API 14 compatible.

[cjhopman, 2013/04/26 20:57:31]

I'd prefer file-level docstring

[Kibeom Kim (inactive), 2013/04/27 00:05:07]

Done.

+
+  """
+
+  options = ParseArgs()
+
+  res_sub_dir_names = os.walk(options.res_dir).next()[1]
+  build_utils.MakeDirectory(options.res_v14_dir)
+
+  for res_sub_dir_name in res_sub_dir_names:
+    dir_pieces = res_sub_dir_name.split('-')
+    resource_type = dir_pieces[0]
+    qualifiers = dir_pieces[1:]
+
+    # We only convert resources under layout*/ and xml*/.
+    if resource_type not in ('layout', 'xml'):
+      continue
+
+    # Android pre-v17 API doesn't support RTL. Skip.
+    if 'ldrtl' in qualifiers:
+      continue
+
+    # Convert all the resource files.
+    generate_v14_resources_in_dir(os.path.join(options.res_dir,
+                                               res_sub_dir_name),
+                                  os.path.join(options.res_v14_dir,
+                                               res_sub_dir_name))
+
+
+if __name__ == '__main__':
+  sys.exit(main(sys.argv))
+