__all__ = [ 'HTML5TreeBuilder', ] import warnings from bs4.builder import ( PERMISSIVE, HTML, HTML_5, HTMLTreeBuilder, ) from bs4.element import NamespacedAttribute import html5lib from html5lib.constants import namespaces from bs4.element import ( Comment, Doctype, NavigableString, Tag, ) class HTML5TreeBuilder(HTMLTreeBuilder): """Use html5lib to build a tree.""" features = ['html5lib', PERMISSIVE, HTML_5, HTML] def prepare_markup(self, markup, user_specified_encoding): # Store the user-specified encoding for use later on. self.user_specified_encoding = user_specified_encoding return 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.") parser = html5lib.HTMLParser(tree=self.create_treebuilder) doc = parser.parse(markup, encoding=self.user_specified_encoding) # Set the character encoding detected by the tokenizer. if isinstance(markup, unicode): # We need to special-case this because html5lib sets # charEncoding to UTF-8 if it gets Unicode input. doc.original_encoding = None else: doc.original_encoding = parser.tokenizer.stream.charEncoding[0] def create_treebuilder(self, namespaceHTMLElements): self.underlying_builder = TreeBuilderForHtml5lib( self.soup, namespaceHTMLElements) return self.underlying_builder def test_fragment_to_document(self, fragment): """See `TreeBuilder`.""" return u'%s' % fragment class TreeBuilderForHtml5lib(html5lib.treebuilders._base.TreeBuilder): def __init__(self, soup, namespaceHTMLElements): self.soup = soup super(TreeBuilderForHtml5lib, self).__init__(namespaceHTMLElements) 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): tag = self.soup.new_tag(name, namespace) return Element(tag, self.soup, namespace) def commentClass(self, data): return TextNode(Comment(data), self.soup) def fragmentClass(self): self.soup = BeautifulSoup("") 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 html5lib.treebuilders._base.TreeBuilder.getFragment(self).element 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): "set attr", name, 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(html5lib.treebuilders._base.Node): def __init__(self, element, soup, namespace): html5lib.treebuilders._base.Node.__init__(self, element.name) self.element = element self.soup = soup self.namespace = namespace def appendChild(self, node): if (node.element.__class__ == NavigableString and self.element.contents and self.element.contents[-1].__class__ == NavigableString): # Concatenate new text onto old text node # XXX This has O(n^2) performance, for input like # "aaa..." old_element = self.element.contents[-1] new_element = self.soup.new_string(old_element + node.element) old_element.replace_with(new_element) else: self.soup.object_was_parsed(node.element, parent=self.element) def getAttributes(self): 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 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, newParent): while self.element.contents: child = self.element.contents[0] child.extract() if isinstance(child, Tag): newParent.appendChild( Element(child, self.soup, namespaces["html"])) else: newParent.appendChild( TextNode(child, self.soup)) 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): html5lib.treebuilders._base.Node.__init__(self, None) self.element = element self.soup = soup def cloneNode(self): raise NotImplementedError