#!/usr/bin/python
#
# Copyright (C) 2012 The Android Open Source Project
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
# http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
#
"""
A parser for metadata_properties.xml can also render the resulting model
over a Mako template.
Usage:
metadata_parser_xml.py <filename.xml> <template.mako> [<output_file>]
- outputs the resulting template to output_file (stdout if none specified)
Module:
The parser is also available as a module import (MetadataParserXml) to use
in other modules.
Dependencies:
BeautifulSoup - an HTML/XML parser available to download from
http://www.crummy.com/software/BeautifulSoup/
Mako - a template engine for Python, available to download from
http://www.makotemplates.org/
"""
import sys
import os
import StringIO
from bs4 import BeautifulSoup
from bs4 import NavigableString
from mako.template import Template
from mako.lookup import TemplateLookup
from mako.runtime import Context
from metadata_model import *
import metadata_model
from metadata_validate import *
import metadata_helpers
class MetadataParserXml:
"""
A class to parse any XML file that passes validation with metadata-validate.
It builds a metadata_model.Metadata graph and then renders it over a
Mako template.
Attributes (Read-Only):
soup: an instance of BeautifulSoup corresponding to the XML contents
metadata: a constructed instance of metadata_model.Metadata
"""
def __init__(self, file_name):
"""
Construct a new MetadataParserXml, immediately try to parse it into a
metadata model.
Args:
file_name: path to an XML file that passes metadata-validate
Raises:
ValueError: if the XML file failed to pass metadata_validate.py
"""
self._soup = validate_xml(file_name)
if self._soup is None:
raise ValueError("%s has an invalid XML file" %(file_name))
self._metadata = Metadata()
self._parse()
self._metadata.construct_graph()
@property
def soup(self):
return self._soup
@property
def metadata(self):
return self._metadata
@staticmethod
def _find_direct_strings(element):
if element.string is not None:
return [element.string]
return [i for i in element.contents if isinstance(i, NavigableString)]
@staticmethod
def _strings_no_nl(element):
return "".join([i.strip() for i in MetadataParserXml._find_direct_strings(element)])
def _parse(self):
tags = self.soup.tags
if tags is not None:
for tag in tags.find_all('tag'):
self.metadata.insert_tag(tag['id'], tag.string)
# add all entries, preserving the ordering of the XML file
# this is important for future ABI compatibility when generating code
entry_filter = lambda x: x.name == 'entry' or x.name == 'clone'
for entry in self.soup.find_all(entry_filter):
if entry.name == 'entry':
d = {
'name': fully_qualified_name(entry),
'type': entry['type'],
'kind': find_kind(entry),
'type_notes': entry.attrs.get('type_notes')
}
d2 = self._parse_entry(entry)
insert = self.metadata.insert_entry
else:
d = {
'name': entry['entry'],
'kind': find_kind(entry),
'target_kind': entry['kind'],
# no type since its the same
# no type_notes since its the same
}
d2 = {}
insert = self.metadata.insert_clone
d3 = self._parse_entry_optional(entry)
entry_dict = dict(d.items() + d2.items() + d3.items())
insert(entry_dict)
self.metadata.construct_graph()
def _parse_entry(self, entry):
d = {}
#
# Enum
#
if entry.get('enum', 'false') == 'true':
enum_values = []
enum_optionals = []
enum_notes = {}
enum_ids = {}
for value in entry.enum.find_all('value'):
value_body = self._strings_no_nl(value)
enum_values.append(value_body)
if value.attrs.get('optional', 'false') == 'true':
enum_optionals.append(value_body)
notes = value.find('notes')
if notes is not None:
enum_notes[value_body] = notes.string
if value.attrs.get('id') is not None:
enum_ids[value_body] = value['id']
d['enum_values'] = enum_values
d['enum_optionals'] = enum_optionals
d['enum_notes'] = enum_notes
d['enum_ids'] = enum_ids
d['enum'] = True
#
# Container (Array/Tuple)
#
if entry.attrs.get('container') is not None:
container_name = entry['container']
array = entry.find('array')
if array is not None:
array_sizes = []
for size in array.find_all('size'):
array_sizes.append(size.string)
d['container_sizes'] = array_sizes
tupl = entry.find('tuple')
if tupl is not None:
tupl_values = []
for val in tupl.find_all('value'):
tupl_values.append(val.name)
d['tuple_values'] = tupl_values
d['container_sizes'] = len(tupl_values)
d['container'] = container_name
return d
def _parse_entry_optional(self, entry):
d = {}
optional_elements = ['description', 'range', 'units', 'notes']
for i in optional_elements:
prop = find_child_tag(entry, i)
if prop is not None:
d[i] = prop.string
tag_ids = []
for tag in entry.find_all('tag'):
tag_ids.append(tag['id'])
d['tag_ids'] = tag_ids
return d
def render(self, template, output_name=None):
"""
Render the metadata model using a Mako template as the view.
The template gets the metadata as an argument, as well as all
public attributes from the metadata_helpers module.
Args:
template: path to a Mako template file
output_name: path to the output file, or None to use stdout
"""
buf = StringIO.StringIO()
metadata_helpers._context_buf = buf
helpers = [(i, getattr(metadata_helpers, i))
for i in dir(metadata_helpers) if not i.startswith('_')]
helpers = dict(helpers)
lookup = TemplateLookup(directories=[os.getcwd()])
tpl = Template(filename=template, lookup=lookup)
ctx = Context(buf, metadata=self.metadata, **helpers)
tpl.render_context(ctx)
tpl_data = buf.getvalue()
metadata_helpers._context_buf = None
buf.close()
if output_name is None:
print tpl_data
else:
file(output_name, "w").write(tpl_data)
#####################
#####################
if __name__ == "__main__":
if len(sys.argv) <= 2:
print >> sys.stderr, \
"Usage: %s <filename.xml> <template.mako> [<output_file>]" \
% (sys.argv[0])
sys.exit(0)
file_name = sys.argv[1]
template_name = sys.argv[2]
output_name = sys.argv[3] if len(sys.argv) > 3 else None
parser = MetadataParserXml(file_name)
parser.render(template_name, output_name)
sys.exit(0)