metadata_parser_xml.py revision ca25627fc63255d147286ef9a9624059825eb548 
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    # Synthetic ?
179    #
180    d['synthetic'] = entry.get('synthetic') == 'true'
181
182    #
183    # Hardware Level (one of limited, legacy, full)
184    #
185    d['hwlevel'] = entry.get('hwlevel')
186
187    #
188    # Deprecated ?
189    #
190    d['deprecated'] = entry.get('deprecated') == 'true'
191
192    #
193    # Optional for non-full hardware level devices
194    #
195    d['optional'] = entry.get('optional') == 'true'
196
197    #
198    # Typedef
199    #
200    d['type_name'] = entry.get('typedef')
201
202    #
203    # Enum
204    #
205    if entry.get('enum', 'false') == 'true':
206
207      enum_values = []
208      enum_optionals = []
209      enum_hiddens = []
210      enum_notes = {}
211      enum_ids = {}
212      for value in entry.enum.find_all('value'):
213
214        value_body = self._strings_no_nl(value)
215        enum_values.append(value_body)
216
217        if value.attrs.get('optional', 'false') == 'true':
218          enum_optionals.append(value_body)
219
220        if value.attrs.get('hidden', 'false') == 'true':
221          enum_hiddens.append(value_body)
222
223        notes = value.find('notes')
224        if notes is not None:
225          enum_notes[value_body] = notes.string
226
227        if value.attrs.get('id') is not None:
228          enum_ids[value_body] = value['id']
229
230      d['enum_values'] = enum_values
231      d['enum_optionals'] = enum_optionals
232      d['enum_hiddens'] = enum_hiddens
233      d['enum_notes'] = enum_notes
234      d['enum_ids'] = enum_ids
235      d['enum'] = True
236
237    #
238    # Container (Array/Tuple)
239    #
240    if entry.attrs.get('container') is not None:
241      container_name = entry['container']
242
243      array = entry.find('array')
244      if array is not None:
245        array_sizes = []
246        for size in array.find_all('size'):
247          array_sizes.append(size.string)
248        d['container_sizes'] = array_sizes
249
250      tupl = entry.find('tuple')
251      if tupl is not None:
252        tupl_values = []
253        for val in tupl.find_all('value'):
254          tupl_values.append(val.name)
255        d['tuple_values'] = tupl_values
256        d['container_sizes'] = len(tupl_values)
257
258      d['container'] = container_name
259
260    return d
261
262  def _parse_entry_optional(self, entry):
263    d = {}
264
265    optional_elements = ['description', 'range', 'units', 'details', 'hal_details']
266    for i in optional_elements:
267      prop = find_child_tag(entry, i)
268
269      if prop is not None:
270        d[i] = prop.string
271
272    tag_ids = []
273    for tag in entry.find_all('tag'):
274      tag_ids.append(tag['id'])
275
276    d['tag_ids'] = tag_ids
277
278    return d
279
280  def render(self, template, output_name=None):
281    """
282    Render the metadata model using a Mako template as the view.
283
284    The template gets the metadata as an argument, as well as all
285    public attributes from the metadata_helpers module.
286
287    The output file is encoded with UTF-8.
288
289    Args:
290      template: path to a Mako template file
291      output_name: path to the output file, or None to use stdout
292    """
293    buf = StringIO.StringIO()
294    metadata_helpers._context_buf = buf
295
296    helpers = [(i, getattr(metadata_helpers, i))
297                for i in dir(metadata_helpers) if not i.startswith('_')]
298    helpers = dict(helpers)
299
300    lookup = TemplateLookup(directories=[os.getcwd()])
301    tpl = Template(filename=template, lookup=lookup)
302
303    ctx = Context(buf, metadata=self.metadata, **helpers)
304    tpl.render_context(ctx)
305
306    tpl_data = buf.getvalue()
307    metadata_helpers._context_buf = None
308    buf.close()
309
310    if output_name is None:
311      print tpl_data
312    else:
313      file(output_name, "w").write(tpl_data.encode('utf-8'))
314
315#####################
316#####################
317
318if __name__ == "__main__":
319  if len(sys.argv) <= 2:
320    print >> sys.stderr,                                                       \
321           "Usage: %s <filename.xml> <template.mako> [<output_file>]"          \
322           % (sys.argv[0])
323    sys.exit(0)
324
325  file_name = sys.argv[1]
326  template_name = sys.argv[2]
327  output_name = sys.argv[3] if len(sys.argv) > 3 else None
328  parser = MetadataParserXml.create_from_file(file_name)
329  parser.render(template_name, output_name)
330
331  sys.exit(0)
332