| # Use of this source code is governed by the MIT license. |
| __license__ = "MIT" |
| |
| __all__ = [ |
| 'HTML5TreeBuilder', |
| ] |
| |
| import warnings |
| import re |
| from bs4.builder import ( |
| DetectsXMLParsedAsHTML, |
| PERMISSIVE, |
| HTML, |
| HTML_5, |
| HTMLTreeBuilder, |
| ) |
| from bs4.element import ( |
| NamespacedAttribute, |
| nonwhitespace_re, |
| ) |
| import html5lib |
| from html5lib.constants import ( |
| namespaces, |
| prefixes, |
| ) |
| from bs4.element import ( |
| Comment, |
| Doctype, |
| NavigableString, |
| Tag, |
| ) |
| |
| try: |
| # Pre-0.99999999 |
| from html5lib.treebuilders import _base as treebuilder_base |
| new_html5lib = False |
| except ImportError as e: |
| # 0.99999999 and up |
| from html5lib.treebuilders import base as treebuilder_base |
| new_html5lib = True |
| |
| class HTML5TreeBuilder(HTMLTreeBuilder): |
| """Use html5lib to build a tree. |
| |
| Note that this TreeBuilder does not support some features common |
| to HTML TreeBuilders. Some of these features could theoretically |
| be implemented, but at the very least it's quite difficult, |
| because html5lib moves the parse tree around as it's being built. |
| |
| * This TreeBuilder doesn't use different subclasses of NavigableString |
| based on the name of the tag in which the string was found. |
| |
| * You can't use a SoupStrainer to parse only part of a document. |
| """ |
| |
| NAME = "html5lib" |
| |
| features = [NAME, PERMISSIVE, HTML_5, HTML] |
| |
| # html5lib can tell us which line number and position in the |
| # original file is the source of an element. |
| TRACKS_LINE_NUMBERS = True |
| |
| def prepare_markup(self, markup, user_specified_encoding, |
| document_declared_encoding=None, exclude_encodings=None): |
| # Store the user-specified encoding for use later on. |
| self.user_specified_encoding = user_specified_encoding |
| |
| # document_declared_encoding and exclude_encodings aren't used |
| # ATM because the html5lib TreeBuilder doesn't use |
| # UnicodeDammit. |
| if exclude_encodings: |
| warnings.warn( |
| "You provided a value for exclude_encoding, but the html5lib tree builder doesn't support exclude_encoding.", |
| stacklevel=3 |
| ) |
| |
| # html5lib only parses HTML, so if it's given XML that's worth |
| # noting. |
| DetectsXMLParsedAsHTML.warn_if_markup_looks_like_xml( |
| markup, stacklevel=3 |
| ) |
| |
| yield (markup, None, None, False) |
| |
| # These methods are defined by Beautiful Soup. |
| def feed(self, markup): |
| if self.soup.parse_only is not None: |
| warnings.warn( |
| "You provided a value for parse_only, but the html5lib tree builder doesn't support parse_only. The entire document will be parsed.", |
| stacklevel=4 |
| ) |
| parser = html5lib.HTMLParser(tree=self.create_treebuilder) |
| self.underlying_builder.parser = parser |
| extra_kwargs = dict() |
| if not isinstance(markup, str): |
| if new_html5lib: |
| extra_kwargs['override_encoding'] = self.user_specified_encoding |
| else: |
| extra_kwargs['encoding'] = self.user_specified_encoding |
| doc = parser.parse(markup, **extra_kwargs) |
| |
| # Set the character encoding detected by the tokenizer. |
| if isinstance(markup, str): |
| # We need to special-case this because html5lib sets |
| # charEncoding to UTF-8 if it gets Unicode input. |
| doc.original_encoding = None |
| else: |
| original_encoding = parser.tokenizer.stream.charEncoding[0] |
| if not isinstance(original_encoding, str): |
| # In 0.99999999 and up, the encoding is an html5lib |
| # Encoding object. We want to use a string for compatibility |
| # with other tree builders. |
| original_encoding = original_encoding.name |
| doc.original_encoding = original_encoding |
| self.underlying_builder.parser = None |
| |
| def create_treebuilder(self, namespaceHTMLElements): |
| self.underlying_builder = TreeBuilderForHtml5lib( |
| namespaceHTMLElements, self.soup, |
| store_line_numbers=self.store_line_numbers |
| ) |
| return self.underlying_builder |
| |
| def test_fragment_to_document(self, fragment): |
| """See `TreeBuilder`.""" |
| return '<html><head></head><body>%s</body></html>' % fragment |
| |
| |
| class TreeBuilderForHtml5lib(treebuilder_base.TreeBuilder): |
| |
| def __init__(self, namespaceHTMLElements, soup=None, |
| store_line_numbers=True, **kwargs): |
| if soup: |
| self.soup = soup |
| else: |
| from bs4 import BeautifulSoup |
| # TODO: Why is the parser 'html.parser' here? To avoid an |
| # infinite loop? |
| self.soup = BeautifulSoup( |
| "", "html.parser", store_line_numbers=store_line_numbers, |
| **kwargs |
| ) |
| # TODO: What are **kwargs exactly? Should they be passed in |
| # here in addition to/instead of being passed to the BeautifulSoup |
| # constructor? |
| super(TreeBuilderForHtml5lib, self).__init__(namespaceHTMLElements) |
| |
| # This will be set later to an html5lib.html5parser.HTMLParser |
| # object, which we can use to track the current line number. |
| self.parser = None |
| self.store_line_numbers = store_line_numbers |
| |
| def documentClass(self): |
| self.soup.reset() |
| return Element(self.soup, self.soup, None) |
| |
| def insertDoctype(self, token): |
| name = token["name"] |
| publicId = token["publicId"] |
| systemId = token["systemId"] |
| |
| doctype = Doctype.for_name_and_ids(name, publicId, systemId) |
| self.soup.object_was_parsed(doctype) |
| |
| def elementClass(self, name, namespace): |
| kwargs = {} |
| if self.parser and self.store_line_numbers: |
| # This represents the point immediately after the end of the |
| # tag. We don't know when the tag started, but we do know |
| # where it ended -- the character just before this one. |
| sourceline, sourcepos = self.parser.tokenizer.stream.position() |
| kwargs['sourceline'] = sourceline |
| kwargs['sourcepos'] = sourcepos-1 |
| tag = self.soup.new_tag(name, namespace, **kwargs) |
| |
| return Element(tag, self.soup, namespace) |
| |
| def commentClass(self, data): |
| return TextNode(Comment(data), self.soup) |
| |
| def fragmentClass(self): |
| from bs4 import BeautifulSoup |
| # TODO: Why is the parser 'html.parser' here? To avoid an |
| # infinite loop? |
| self.soup = BeautifulSoup("", "html.parser") |
| self.soup.name = "[document_fragment]" |
| return Element(self.soup, self.soup, None) |
| |
| def appendChild(self, node): |
| # XXX This code is not covered by the BS4 tests. |
| self.soup.append(node.element) |
| |
| def getDocument(self): |
| return self.soup |
| |
| def getFragment(self): |
| return treebuilder_base.TreeBuilder.getFragment(self).element |
| |
| def testSerializer(self, element): |
| from bs4 import BeautifulSoup |
| rv = [] |
| doctype_re = re.compile(r'^(.*?)(?: PUBLIC "(.*?)"(?: "(.*?)")?| SYSTEM "(.*?)")?$') |
| |
| def serializeElement(element, indent=0): |
| if isinstance(element, BeautifulSoup): |
| pass |
| if isinstance(element, Doctype): |
| m = doctype_re.match(element) |
| if m: |
| name = m.group(1) |
| if m.lastindex > 1: |
| publicId = m.group(2) or "" |
| systemId = m.group(3) or m.group(4) or "" |
| rv.append("""|%s<!DOCTYPE %s "%s" "%s">""" % |
| (' ' * indent, name, publicId, systemId)) |
| else: |
| rv.append("|%s<!DOCTYPE %s>" % (' ' * indent, name)) |
| else: |
| rv.append("|%s<!DOCTYPE >" % (' ' * indent,)) |
| elif isinstance(element, Comment): |
| rv.append("|%s<!-- %s -->" % (' ' * indent, element)) |
| elif isinstance(element, NavigableString): |
| rv.append("|%s\"%s\"" % (' ' * indent, element)) |
| else: |
| if element.namespace: |
| name = "%s %s" % (prefixes[element.namespace], |
| element.name) |
| else: |
| name = element.name |
| rv.append("|%s<%s>" % (' ' * indent, name)) |
| if element.attrs: |
| attributes = [] |
| for name, value in list(element.attrs.items()): |
| if isinstance(name, NamespacedAttribute): |
| name = "%s %s" % (prefixes[name.namespace], name.name) |
| if isinstance(value, list): |
| value = " ".join(value) |
| attributes.append((name, value)) |
| |
| for name, value in sorted(attributes): |
| rv.append('|%s%s="%s"' % (' ' * (indent + 2), name, value)) |
| indent += 2 |
| for child in element.children: |
| serializeElement(child, indent) |
| serializeElement(element, 0) |
| |
| return "\n".join(rv) |
| |
| class AttrList(object): |
| def __init__(self, element): |
| self.element = element |
| self.attrs = dict(self.element.attrs) |
| def __iter__(self): |
| return list(self.attrs.items()).__iter__() |
| def __setitem__(self, name, value): |
| # If this attribute is a multi-valued attribute for this element, |
| # turn its value into a list. |
| list_attr = self.element.cdata_list_attributes or {} |
| if (name in list_attr.get('*', []) |
| or (self.element.name in list_attr |
| and name in list_attr.get(self.element.name, []))): |
| # A node that is being cloned may have already undergone |
| # this procedure. |
| if not isinstance(value, list): |
| value = nonwhitespace_re.findall(value) |
| self.element[name] = value |
| def items(self): |
| return list(self.attrs.items()) |
| def keys(self): |
| return list(self.attrs.keys()) |
| def __len__(self): |
| return len(self.attrs) |
| def __getitem__(self, name): |
| return self.attrs[name] |
| def __contains__(self, name): |
| return name in list(self.attrs.keys()) |
| |
| |
| class Element(treebuilder_base.Node): |
| def __init__(self, element, soup, namespace): |
| treebuilder_base.Node.__init__(self, element.name) |
| self.element = element |
| self.soup = soup |
| self.namespace = namespace |
| |
| def appendChild(self, node): |
| string_child = child = None |
| if isinstance(node, str): |
| # Some other piece of code decided to pass in a string |
| # instead of creating a TextElement object to contain the |
| # string. |
| string_child = child = node |
| elif isinstance(node, Tag): |
| # Some other piece of code decided to pass in a Tag |
| # instead of creating an Element object to contain the |
| # Tag. |
| child = node |
| elif node.element.__class__ == NavigableString: |
| string_child = child = node.element |
| node.parent = self |
| else: |
| child = node.element |
| node.parent = self |
| |
| if not isinstance(child, str) and child.parent is not None: |
| node.element.extract() |
| |
| if (string_child is not None and self.element.contents |
| and self.element.contents[-1].__class__ == NavigableString): |
| # We are appending a string onto another string. |
| # TODO This has O(n^2) performance, for input like |
| # "a</a>a</a>a</a>..." |
| old_element = self.element.contents[-1] |
| new_element = self.soup.new_string(old_element + string_child) |
| old_element.replace_with(new_element) |
| self.soup._most_recent_element = new_element |
| else: |
| if isinstance(node, str): |
| # Create a brand new NavigableString from this string. |
| child = self.soup.new_string(node) |
| |
| # Tell Beautiful Soup to act as if it parsed this element |
| # immediately after the parent's last descendant. (Or |
| # immediately after the parent, if it has no children.) |
| if self.element.contents: |
| most_recent_element = self.element._last_descendant(False) |
| elif self.element.next_element is not None: |
| # Something from further ahead in the parse tree is |
| # being inserted into this earlier element. This is |
| # very annoying because it means an expensive search |
| # for the last element in the tree. |
| most_recent_element = self.soup._last_descendant() |
| else: |
| most_recent_element = self.element |
| |
| self.soup.object_was_parsed( |
| child, parent=self.element, |
| most_recent_element=most_recent_element) |
| |
| def getAttributes(self): |
| if isinstance(self.element, Comment): |
| return {} |
| return AttrList(self.element) |
| |
| def setAttributes(self, attributes): |
| if attributes is not None and len(attributes) > 0: |
| converted_attributes = [] |
| for name, value in list(attributes.items()): |
| if isinstance(name, tuple): |
| new_name = NamespacedAttribute(*name) |
| del attributes[name] |
| attributes[new_name] = value |
| |
| self.soup.builder._replace_cdata_list_attribute_values( |
| self.name, attributes) |
| for name, value in list(attributes.items()): |
| self.element[name] = value |
| |
| # The attributes may contain variables that need substitution. |
| # Call set_up_substitutions manually. |
| # |
| # The Tag constructor called this method when the Tag was created, |
| # but we just set/changed the attributes, so call it again. |
| self.soup.builder.set_up_substitutions(self.element) |
| attributes = property(getAttributes, setAttributes) |
| |
| def insertText(self, data, insertBefore=None): |
| text = TextNode(self.soup.new_string(data), self.soup) |
| if insertBefore: |
| self.insertBefore(text, insertBefore) |
| else: |
| self.appendChild(text) |
| |
| def insertBefore(self, node, refNode): |
| index = self.element.index(refNode.element) |
| if (node.element.__class__ == NavigableString and self.element.contents |
| and self.element.contents[index-1].__class__ == NavigableString): |
| # (See comments in appendChild) |
| old_node = self.element.contents[index-1] |
| new_str = self.soup.new_string(old_node + node.element) |
| old_node.replace_with(new_str) |
| else: |
| self.element.insert(index, node.element) |
| node.parent = self |
| |
| def removeChild(self, node): |
| node.element.extract() |
| |
| def reparentChildren(self, new_parent): |
| """Move all of this tag's children into another tag.""" |
| # print("MOVE", self.element.contents) |
| # print("FROM", self.element) |
| # print("TO", new_parent.element) |
| |
| element = self.element |
| new_parent_element = new_parent.element |
| # Determine what this tag's next_element will be once all the children |
| # are removed. |
| final_next_element = element.next_sibling |
| |
| new_parents_last_descendant = new_parent_element._last_descendant(False, False) |
| if len(new_parent_element.contents) > 0: |
| # The new parent already contains children. We will be |
| # appending this tag's children to the end. |
| new_parents_last_child = new_parent_element.contents[-1] |
| new_parents_last_descendant_next_element = new_parents_last_descendant.next_element |
| else: |
| # The new parent contains no children. |
| new_parents_last_child = None |
| new_parents_last_descendant_next_element = new_parent_element.next_element |
| |
| to_append = element.contents |
| if len(to_append) > 0: |
| # Set the first child's previous_element and previous_sibling |
| # to elements within the new parent |
| first_child = to_append[0] |
| if new_parents_last_descendant is not None: |
| first_child.previous_element = new_parents_last_descendant |
| else: |
| first_child.previous_element = new_parent_element |
| first_child.previous_sibling = new_parents_last_child |
| if new_parents_last_descendant is not None: |
| new_parents_last_descendant.next_element = first_child |
| else: |
| new_parent_element.next_element = first_child |
| if new_parents_last_child is not None: |
| new_parents_last_child.next_sibling = first_child |
| |
| # Find the very last element being moved. It is now the |
| # parent's last descendant. It has no .next_sibling and |
| # its .next_element is whatever the previous last |
| # descendant had. |
| last_childs_last_descendant = to_append[-1]._last_descendant(False, True) |
| |
| last_childs_last_descendant.next_element = new_parents_last_descendant_next_element |
| if new_parents_last_descendant_next_element is not None: |
| # TODO: This code has no test coverage and I'm not sure |
| # how to get html5lib to go through this path, but it's |
| # just the other side of the previous line. |
| new_parents_last_descendant_next_element.previous_element = last_childs_last_descendant |
| last_childs_last_descendant.next_sibling = None |
| |
| for child in to_append: |
| child.parent = new_parent_element |
| new_parent_element.contents.append(child) |
| |
| # Now that this element has no children, change its .next_element. |
| element.contents = [] |
| element.next_element = final_next_element |
| |
| # print("DONE WITH MOVE") |
| # print("FROM", self.element) |
| # print("TO", new_parent_element) |
| |
| def cloneNode(self): |
| tag = self.soup.new_tag(self.element.name, self.namespace) |
| node = Element(tag, self.soup, self.namespace) |
| for key,value in self.attributes: |
| node.attributes[key] = value |
| return node |
| |
| def hasContent(self): |
| return self.element.contents |
| |
| def getNameTuple(self): |
| if self.namespace == None: |
| return namespaces["html"], self.name |
| else: |
| return self.namespace, self.name |
| |
| nameTuple = property(getNameTuple) |
| |
| class TextNode(Element): |
| def __init__(self, element, soup): |
| treebuilder_base.Node.__init__(self, None) |
| self.element = element |
| self.soup = soup |
| |
| def cloneNode(self): |
| raise NotImplementedError |
