1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
|
# -*- coding: utf-8 -*-
#
# Copyright (c) 2020 Martin Owens <doctormo@gmail.com>
# Sergei Izmailov <sergei.a.izmailov@gmail.com>
# Thomas Holder <thomas.holder@schrodinger.com>
#
# This program 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.
#
# This program 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.
#
"""Utilities for parsing SVG documents.
.. versionadded:: 1.2
Separated out from :py:mod:`inkex.elements._base`"""
from collections import defaultdict
from typing import DefaultDict, List, Any, Type
from lxml import etree
from ..interfaces.IElement import IBaseElement
from ._utils import splitNS
from ..utils import errormsg
from ..localization import inkex_gettext as _
class NodeBasedLookup(etree.PythonElementClassLookup):
"""
We choose what kind of Elements we should return for each element, providing useful
SVG based API to our extensions system.
"""
default: Type[IBaseElement]
# (ns,tag) -> list(cls) ; ascending priority
lookup_table = defaultdict(list) # type: DefaultDict[str, List[Any]]
@classmethod
def register_class(cls, klass):
"""Register the given class using it's attached tag name"""
cls.lookup_table[splitNS(klass.tag_name)].append(klass)
@classmethod
def find_class(cls, xpath):
"""Find the class for this type of element defined by an xpath
.. versionadded:: 1.1"""
if isinstance(xpath, type):
return xpath
for kls in cls.lookup_table[splitNS(xpath.split("/")[-1])]:
# TODO: We could create a apply the xpath attrs to the test element
# to narrow the search, but this does everything we need right now.
test_element = kls()
if kls.is_class_element(test_element):
return kls
raise KeyError(f"Could not find svg tag for '{xpath}'")
def lookup(self, doc, element): # pylint: disable=unused-argument
"""Lookup called by lxml when assigning elements their object class"""
try:
for kls in reversed(self.lookup_table[splitNS(element.tag)]):
if kls.is_class_element(element): # pylint: disable=protected-access
return kls
except TypeError:
# Handle non-element proxies case
# The documentation implies that it's not possible
# Didn't found a reliable way to check whether proxy corresponds to element
# or not
# Look like lxml issue to me.
# The troubling element is "<!--Comment-->"
return None
return NodeBasedLookup.default
SVG_PARSER = etree.XMLParser(huge_tree=True, strip_cdata=False, recover=True)
SVG_PARSER.set_element_class_lookup(NodeBasedLookup())
def load_svg(stream):
"""Load SVG file using the SVG_PARSER"""
if (isinstance(stream, str) and stream.lstrip().startswith("<")) or (
isinstance(stream, bytes) and stream.lstrip().startswith(b"<")
):
parsed = etree.ElementTree(etree.fromstring(stream, parser=SVG_PARSER))
else:
parsed = etree.parse(stream, parser=SVG_PARSER)
if len(SVG_PARSER.error_log) > 0:
errormsg(
_(
"A parsing error occured, which means you are likely working with "
"a non-conformant SVG file. The following errors were found:\n"
)
)
for __, element in enumerate(SVG_PARSER.error_log):
errormsg(
_("{}. Line {}, column {}").format(
element.message, element.line, element.column
)
)
errormsg(
_(
"\nProcessing will continue; however we encourage you to fix your"
" file manually."
)
)
return parsed
|
