Mark McKinnon edd20e506d GPX internal python module update
GPX internal pythong module update for open source and geoartifacthelper
2020-01-31 15:29:38 -05:00

222 lines
6.5 KiB
Python

# -*- coding: utf-8 -*-
# Copyright 2011 Tomo Krajina
#
# 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.
from __future__ import print_function
import pdb
import re as mod_re
import logging as mod_logging
import datetime as mod_datetime
import xml.dom.minidom as mod_minidom
try:
import lxml.etree as mod_etree
except:
mod_etree = None
pass # LXML not available
from . import gpx as mod_gpx
from . import utils as mod_utils
from . import gpxfield as mod_gpxfield
class XMLParser:
"""
Used when lxml is not available. Uses standard minidom.
"""
def __init__(self, xml):
self.xml = xml
self.dom = mod_minidom.parseString(xml)
def get_first_child(self, node=None, name=None):
# TODO: Remove find_first_node from utils!
if not node:
node = self.dom
children = node.childNodes
if not children:
return None
if not name:
return children[0]
for tmp_node in children:
if tmp_node.nodeName == name:
return tmp_node
return None
def get_node_name(self, node):
if not node:
return None
return node.nodeName
def get_children(self, node=None):
if not node:
node = self.dom
return list(filter(lambda node : node.nodeType == node.ELEMENT_NODE, node.childNodes))
def get_node_data(self, node):
if node is None:
return None
child_nodes = node.childNodes
if not child_nodes or len(child_nodes) == 0:
return None
return child_nodes[0].nodeValue
def get_node_attribute(self, node, attribute):
if (not hasattr(node, 'attributes')) or (not node.attributes):
return None
if attribute in node.attributes.keys():
return node.attributes[attribute].nodeValue
return None
class LXMLParser:
"""
Used when lxml is available.
"""
def __init__(self, xml):
if not mod_etree:
raise Exception('Cannot use LXMLParser without lxml installed')
if mod_utils.PYTHON_VERSION[0] == '3':
# In python 3 all strings are unicode and for some reason lxml
# don't like unicode strings with XMLs declared as UTF-8:
self.xml = xml.encode('utf-8')
else:
self.xml = xml
self.dom = mod_etree.XML(self.xml)
# get the namespace
self.ns = self.dom.nsmap.get(None)
def get_first_child(self, node=None, name=None):
if node is None:
if name:
if self.get_node_name(self.dom) == name:
return self.dom
return self.dom
children = node.getchildren()
if not children:
return None
if name:
for node in children:
if self.get_node_name(node) == name:
return node
return None
return children[0]
def get_node_name(self, node):
if callable(node.tag):
tag = str(node.tag())
else:
tag = str(node.tag)
if '}' in tag:
return tag.split('}')[1]
return tag
def get_children(self, node=None):
if node is None:
node = self.dom
return node.getchildren()
def get_node_data(self, node):
if node is None:
return None
return node.text
def get_node_attribute(self, node, attribute):
if node is None:
return None
return node.attrib.get(attribute)
class GPXParser:
def __init__(self, xml_or_file=None, parser=None):
"""
Parser may be lxml of minidom. If you set to None then lxml will be used if installed
otherwise minidom.
"""
self.init(xml_or_file)
self.gpx = mod_gpx.GPX()
self.xml_parser_type = parser
self.xml_parser = None
def init(self, xml_or_file):
text = xml_or_file.read() if hasattr(xml_or_file, 'read') else xml_or_file
self.xml = mod_utils.make_str(text)
self.gpx = mod_gpx.GPX()
def parse(self):
"""
Parses the XML file and returns a GPX object.
It will throw GPXXMLSyntaxException if the XML file is invalid or
GPXException if the XML file is valid but something is wrong with the
GPX data.
"""
try:
if self.xml_parser_type is None:
if mod_etree:
self.xml_parser = LXMLParser(self.xml)
else:
self.xml_parser = XMLParser(self.xml)
elif self.xml_parser_type == 'lxml':
self.xml_parser = LXMLParser(self.xml)
elif self.xml_parser_type == 'minidom':
self.xml_parser = XMLParser(self.xml)
else:
raise mod_gpx.GPXException('Invalid parser type: %s' % self.xml_parser_type)
self.__parse_dom()
return self.gpx
except Exception as e:
# The exception here can be a lxml or minidom exception.
mod_logging.debug('Error in:\n%s\n-----------\n' % self.xml)
mod_logging.exception(e)
# The library should work in the same way regardless of the
# underlying XML parser that's why the exception thrown
# here is GPXXMLSyntaxException (instead of simply throwing the
# original minidom or lxml exception e).
#
# But, if the user need the original exception (lxml or minidom)
# it is available with GPXXMLSyntaxException.original_exception:
raise mod_gpx.GPXXMLSyntaxException('Error parsing XML: %s' % str(e), e)
def __parse_dom(self):
node = self.xml_parser.get_first_child(name='gpx')
if node is None:
raise mod_gpx.GPXException('Document must have a `gpx` root node.')
version = self.xml_parser.get_node_attribute(node, 'version')
mod_gpxfield.gpx_fields_from_xml(self.gpx, self.xml_parser, node, version)