diff options
| author | Sebastian Koslowski <koslowski@kit.edu> | 2015-11-20 17:28:17 +0100 |
|---|---|---|
| committer | Sebastian Koslowski <koslowski@kit.edu> | 2016-02-17 19:55:16 +0100 |
| commit | 9f5ef34ac05de070a99fae07eb1a8087ba60a653 (patch) | |
| tree | 44ab20b78404c94e85689b8511521e7456d58e3d /grc/python/base/ParseXML.py | |
| parent | 64f3b70cf135a8641a0271ee27b431e05a8df97b (diff) | |
grc-refactor: move grc.base to grc.python.base
Diffstat (limited to 'grc/python/base/ParseXML.py')
| -rw-r--r-- | grc/python/base/ParseXML.py | 155 |
1 files changed, 155 insertions, 0 deletions
diff --git a/grc/python/base/ParseXML.py b/grc/python/base/ParseXML.py new file mode 100644 index 0000000000..2d5fed0862 --- /dev/null +++ b/grc/python/base/ParseXML.py @@ -0,0 +1,155 @@ +""" +Copyright 2008 Free Software Foundation, Inc. +This file is part of GNU Radio + +GNU Radio Companion is free software; you can redistribute it and/or +modify it under the terms of the GNU General Public License +as published by the Free Software Foundation; either version 2 +of the License, or (at your option) any later version. + +GNU Radio Companion is distributed in the hope that it will be useful, +but WITHOUT ANY WARRANTY; without even the implied warranty of +MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the +GNU General Public License for more details. + +You should have received a copy of the GNU General Public License +along with this program; if not, write to the Free Software +Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA +""" + +from lxml import etree +from . import odict + +xml_failures = {} + + +class XMLSyntaxError(Exception): + def __init__(self, error_log): + self._error_log = error_log + xml_failures[error_log.last_error.filename] = error_log + + def __str__(self): + return '\n'.join(map(str, self._error_log.filter_from_errors())) + + +def validate_dtd(xml_file, dtd_file=None): + """ + Validate an xml file against its dtd. + + Args: + xml_file: the xml file + dtd_file: the optional dtd file + @throws Exception validation fails + """ + # perform parsing, use dtd validation if dtd file is not specified + parser = etree.XMLParser(dtd_validation=not dtd_file) + try: + xml = etree.parse(xml_file, parser=parser) + except etree.LxmlError: + pass + if parser.error_log: + raise XMLSyntaxError(parser.error_log) + + # perform dtd validation if the dtd file is specified + if not dtd_file: + return + try: + dtd = etree.DTD(dtd_file) + if not dtd.validate(xml.getroot()): + raise XMLSyntaxError(dtd.error_log) + except etree.LxmlError: + raise XMLSyntaxError(dtd.error_log) + + +def from_file(xml_file): + """ + Create nested data from an xml file using the from xml helper. + Also get the grc version information. + + Args: + xml_file: the xml file path + + Returns: + the nested data with grc version information + """ + xml = etree.parse(xml_file) + nested_data = _from_file(xml.getroot()) + + # Get the embedded instructions and build a dictionary item + nested_data['_instructions'] = {} + xml_instructions = xml.xpath('/processing-instruction()') + for inst in filter(lambda i: i.target == 'grc', xml_instructions): + nested_data['_instructions'] = odict(inst.attrib) + return nested_data + + +def _from_file(xml): + """ + Recursively parse the xml tree into nested data format. + + Args: + xml: the xml tree + + Returns: + the nested data + """ + tag = xml.tag + if not len(xml): + return odict({tag: xml.text or ''}) # store empty tags (text is None) as empty string + nested_data = odict() + for elem in xml: + key, value = _from_file(elem).items()[0] + if nested_data.has_key(key): nested_data[key].append(value) + else: nested_data[key] = [value] + # delistify if the length of values is 1 + for key, values in nested_data.iteritems(): + if len(values) == 1: + nested_data[key] = values[0] + + return odict({tag: nested_data}) + + +def to_file(nested_data, xml_file): + """ + Write to an xml file and insert processing instructions for versioning + + Args: + nested_data: the nested data + xml_file: the xml file path + """ + xml_data = "" + instructions = nested_data.pop('_instructions', None) + if instructions: # create the processing instruction from the array + xml_data += etree.tostring(etree.ProcessingInstruction( + 'grc', ' '.join( + "{0}='{1}'".format(*item) for item in instructions.iteritems()) + ), xml_declaration=True, pretty_print=True, encoding='utf-8') + xml_data += etree.tostring(_to_file(nested_data)[0], + pretty_print=True, encoding='utf-8') + with open(xml_file, 'w') as fp: + fp.write(xml_data) + + +def _to_file(nested_data): + """ + Recursively parse the nested data into xml tree format. + + Args: + nested_data: the nested data + + Returns: + the xml tree filled with child nodes + """ + nodes = list() + for key, values in nested_data.iteritems(): + # listify the values if not a list + if not isinstance(values, (list, set, tuple)): + values = [values] + for value in values: + node = etree.Element(key) + if isinstance(value, (str, unicode)): + node.text = unicode(value) + else: + node.extend(_to_file(value)) + nodes.append(node) + return nodes |