metadata_parser_xml.py revision 63c0fb27d923a32d9a398471ad318bfe84befbeb 
1#!/usr/bin/python
2
3#
4# Copyright (C) 2012 The Android Open Source Project
5#
6# Licensed under the Apache License, Version 2.0 (the "License");
7# you may not use this file except in compliance with the License.
8# You may obtain a copy of the License at
9#
10#      http://www.apache.org/licenses/LICENSE-2.0
11#
12# Unless required by applicable law or agreed to in writing, software
13# distributed under the License is distributed on an "AS IS" BASIS,
14# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
15# See the License for the specific language governing permissions and
16# limitations under the License.
17#
18
19"""
20A parser for metadata_properties.xml can also render the resulting model
21over a Mako template.
22
23Usage:
24  metadata_parser_xml.py <filename.xml> <template.mako> [<output_file>]
25  - outputs the resulting template to output_file (stdout if none specified)
26
27Module:
28  The parser is also available as a module import (MetadataParserXml) to use
29  in other modules.
30
31Dependencies:
32  BeautifulSoup - an HTML/XML parser available to download from
33          http://www.crummy.com/software/BeautifulSoup/
34  Mako - a template engine for Python, available to download from
35     http://www.makotemplates.org/
36"""
37
38import sys
39import os
40import StringIO
41
42from bs4 import BeautifulSoup
43from bs4 import NavigableString
44
45from mako.template import Template
46from mako.lookup import TemplateLookup
47from mako.runtime import Context
48
49from metadata_model import *
50import metadata_model
51from metadata_validate import *
52import metadata_helpers
53
54class MetadataParserXml:
55  """
56  A class to parse any XML block that passes validation with metadata-validate.
57  It builds a metadata_model.Metadata graph and then renders it over a
58  Mako template.
59
60  Attributes (Read-Only):
61    soup: an instance of BeautifulSoup corresponding to the XML contents
62    metadata: a constructed instance of metadata_model.Metadata
63  """
64  def __init__(self, xml, file_name):
65    """
66    Construct a new MetadataParserXml, immediately try to parse it into a
67    metadata model.
68
69    Args:
70      xml: The XML block to use for the metadata
71      file_name: Source of the XML block, only for debugging/errors
72
73    Raises:
74      ValueError: if the XML block failed to pass metadata_validate.py
75    """
76    self._soup = validate_xml(xml)
77
78    if self._soup is None:
79      raise ValueError("%s has an invalid XML file" % (file_name))
80
81    self._metadata = Metadata()
82    self._parse()
83    self._metadata.construct_graph()
84
85  @staticmethod
86  def create_from_file(file_name):
87    """
88    Construct a new MetadataParserXml by loading and parsing an XML file.
89
90    Args:
91      file_name: Name of the XML file to load and parse.
92
93    Raises:
94      ValueError: if the XML file failed to pass metadata_validate.py
95
96    Returns:
97      MetadataParserXml instance representing the XML file.
98    """
99    return MetadataParserXml(file(file_name).read(), file_name)
100
101  @property
102  def soup(self):
103    return self._soup
104
105  @property
106  def metadata(self):
107    return self._metadata
108
109  @staticmethod
110  def _find_direct_strings(element):
111    if element.string is not None:
112      return [element.string]
113
114    return [i for i in element.contents if isinstance(i, NavigableString)]
115
116  @staticmethod
117  def _strings_no_nl(element):
118    return "".join([i.strip() for i in MetadataParserXml._find_direct_strings(element)])
119
120  def _parse(self):
121
122    tags = self.soup.tags
123    if tags is not None:
124      for tag in tags.find_all('tag'):
125        self.metadata.insert_tag(tag['id'], tag.string)
126
127    types = self.soup.types
128    if types is not None:
129      for tp in types.find_all('typedef'):
130        languages = {}
131        for lang in tp.find_all('language'):
132          languages[lang['name']] = lang.string
133
134        self.metadata.insert_type(tp['name'], 'typedef', languages=languages)
135
136    # add all entries, preserving the ordering of the XML file
137    # this is important for future ABI compatibility when generating code
138    entry_filter = lambda x: x.name == 'entry' or x.name == 'clone'
139    for entry in self.soup.find_all(entry_filter):
140      if entry.name == 'entry':
141        d = {
142              'name': fully_qualified_name(entry),
143              'type': entry['type'],
144              'kind': find_kind(entry),
145              'type_notes': entry.attrs.get('type_notes')
146            }
147
148        d2 = self._parse_entry(entry)
149        insert = self.metadata.insert_entry
150      else:
151        d = {
152           'name': entry['entry'],
153           'kind': find_kind(entry),
154           'target_kind': entry['kind'],
155          # no type since its the same
156          # no type_notes since its the same
157        }
158        d2 = {}
159
160        insert = self.metadata.insert_clone
161
162      d3 = self._parse_entry_optional(entry)
163
164      entry_dict = dict(d.items() + d2.items() + d3.items())
165      insert(entry_dict)
166
167    self.metadata.construct_graph()
168
169  def _parse_entry(self, entry):
170    d = {}
171
172    #
173    # Visibility
174    #
175    d['visibility'] = entry.get('visibility')
176
177    #
178    # Optional for non-full hardware level devices
179    #
180    d['optional'] = entry.get('optional') == 'true'
181
182    #
183    # Typedef
184    #
185    d['type_name'] = entry.get('typedef')
186
187    #
188    # Enum
189    #
190    if entry.get('enum', 'false') == 'true':
191
192      enum_values = []
193      enum_optionals = []
194      enum_notes = {}
195      enum_ids = {}
196      for value in entry.enum.find_all('value'):
197
198        value_body = self._strings_no_nl(value)
199        enum_values.append(value_body)
200
201        if value.attrs.get('optional', 'false') == 'true':
202          enum_optionals.append(value_body)
203
204        notes = value.find('notes')
205        if notes is not None:
206          enum_notes[value_body] = notes.string
207
208        if value.attrs.get('id') is not None:
209          enum_ids[value_body] = value['id']
210
211      d['enum_values'] = enum_values
212      d['enum_optionals'] = enum_optionals
213      d['enum_notes'] = enum_notes
214      d['enum_ids'] = enum_ids
215      d['enum'] = True
216
217    #
218    # Container (Array/Tuple)
219    #
220    if entry.attrs.get('container') is not None:
221      container_name = entry['container']
222
223      array = entry.find('array')
224      if array is not None:
225        array_sizes = []
226        for size in array.find_all('size'):
227          array_sizes.append(size.string)
228        d['container_sizes'] = array_sizes
229
230      tupl = entry.find('tuple')
231      if tupl is not None:
232        tupl_values = []
233        for val in tupl.find_all('value'):
234          tupl_values.append(val.name)
235        d['tuple_values'] = tupl_values
236        d['container_sizes'] = len(tupl_values)
237
238      d['container'] = container_name
239
240    return d
241
242  def _parse_entry_optional(self, entry):
243    d = {}
244
245    optional_elements = ['description', 'range', 'units', 'details', 'hal_details']
246    for i in optional_elements:
247      prop = find_child_tag(entry, i)
248
249      if prop is not None:
250        d[i] = prop.string
251
252    tag_ids = []
253    for tag in entry.find_all('tag'):
254      tag_ids.append(tag['id'])
255
256    d['tag_ids'] = tag_ids
257
258    return d
259
260  def render(self, template, output_name=None):
261    """
262    Render the metadata model using a Mako template as the view.
263
264    The template gets the metadata as an argument, as well as all
265    public attributes from the metadata_helpers module.
266
267    The output file is encoded with UTF-8.
268
269    Args:
270      template: path to a Mako template file
271      output_name: path to the output file, or None to use stdout
272    """
273    buf = StringIO.StringIO()
274    metadata_helpers._context_buf = buf
275
276    helpers = [(i, getattr(metadata_helpers, i))
277                for i in dir(metadata_helpers) if not i.startswith('_')]
278    helpers = dict(helpers)
279
280    lookup = TemplateLookup(directories=[os.getcwd()])
281    tpl = Template(filename=template, lookup=lookup)
282
283    ctx = Context(buf, metadata=self.metadata, **helpers)
284    tpl.render_context(ctx)
285
286    tpl_data = buf.getvalue()
287    metadata_helpers._context_buf = None
288    buf.close()
289
290    if output_name is None:
291      print tpl_data
292    else:
293      file(output_name, "w").write(tpl_data.encode('utf-8'))
294
295#####################
296#####################
297
298if __name__ == "__main__":
299  if len(sys.argv) <= 2:
300    print >> sys.stderr,                                                       \
301           "Usage: %s <filename.xml> <template.mako> [<output_file>]"          \
302           % (sys.argv[0])
303    sys.exit(0)
304
305  file_name = sys.argv[1]
306  template_name = sys.argv[2]
307  output_name = sys.argv[3] if len(sys.argv) > 3 else None
308  parser = MetadataParserXml.create_from_file(file_name)
309  parser.render(template_name, output_name)
310
311  sys.exit(0)
312