summaryrefslogtreecommitdiff
path: root/bs4/builder/_lxml.py
blob: 7219e495b394ea693c4570695a51698adb3d2585 (plain)
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
__all__ = [
    'LXMLTreeBuilderForXML',
    'LXMLTreeBuilder',
    ]

import collections
from lxml import etree
from bs4.element import Comment, Doctype
from bs4.builder import (
    FAST,
    HTML,
    HTMLTreeBuilder,
    PERMISSIVE,
    TreeBuilder,
    XML)
from bs4.dammit import UnicodeDammit

LXML = 'lxml'

class LXMLTreeBuilderForXML(TreeBuilder):
    DEFAULT_PARSER_CLASS = etree.XMLParser

    is_xml = True

    # Well, it's permissive by XML parser standards.
    features = [LXML, XML, FAST, PERMISSIVE]

    @property
    def default_parser(self):
        # This can either return a parser object or a class, which
        # will be instantiated with default arguments.
        return etree.XMLParser(target=self, strip_cdata=False, recover=True)

    def __init__(self, parser=None, empty_element_tags=None):
        if empty_element_tags is not None:
            self.empty_element_tags = set(empty_element_tags)
        if parser is None:
            # Use the default parser.
            parser = self.default_parser
        if isinstance(parser, collections.Callable):
            # Instantiate the parser with default arguments
            parser = parser(target=self, strip_cdata=False)
        self.parser = parser
        self.soup = None

    def prepare_markup(self, markup, user_specified_encoding=None,
                       document_declared_encoding=None):
        """
        :return: A 3-tuple (markup, original encoding, encoding
        declared within markup).
        """
        if isinstance(markup, unicode):
            return markup, None, None

        try_encodings = [user_specified_encoding, document_declared_encoding]
        dammit = UnicodeDammit(markup, try_encodings, is_html=True)
        return (dammit.markup, dammit.original_encoding,
                dammit.declared_html_encoding)

    def feed(self, markup):
        self.parser.feed(markup)
        self.parser.close()

    def close(self):
        pass

    def start(self, name, attrs):
        self.soup.handle_starttag(name, attrs)

    def end(self, name):
        self.soup.endData()
        completed_tag = self.soup.tagStack[-1]
        self.soup.handle_endtag(name)

    def pi(self, target, data):
        pass

    def data(self, content):
        self.soup.handle_data(content)

    def doctype(self, name, pubid, system):
        self.soup.endData()
        doctype = Doctype.for_name_and_ids(name, pubid, system)
        self.soup.object_was_parsed(doctype)

    def comment(self, content):
        "Handle comments as Comment objects."
        self.soup.endData()
        self.soup.handle_data(content)
        self.soup.endData(Comment)

    def test_fragment_to_document(self, fragment):
        """See `TreeBuilder`."""
        return u'<?xml version="1.0" encoding="utf-8">\n%s' % fragment


class LXMLTreeBuilder(HTMLTreeBuilder, LXMLTreeBuilderForXML):

    features = [LXML, HTML, FAST, PERMISSIVE]
    is_xml = False

    @property
    def default_parser(self):
        return etree.HTMLParser

    def test_fragment_to_document(self, fragment):
        """See `TreeBuilder`."""
        return u'<html><body>%s</body></html>' % fragment