# coding: utf-8 # frozen_string_literal: true require "pathname" module Nokogiri module HTML4 class Document < Nokogiri::XML::Document ### # Get the meta tag encoding for this document. If there is no meta tag, # then nil is returned. def meta_encoding if (meta = at_xpath("//meta[@charset]")) meta[:charset] elsif (meta = meta_content_type) meta["content"][/charset\s*=\s*([\w-]+)/i, 1] end end ### # Set the meta tag encoding for this document. # # If an meta encoding tag is already present, its content is # replaced with the given text. # # Otherwise, this method tries to create one at an appropriate # place supplying head and/or html elements as necessary, which # is inside a head element if any, and before any text node or # content element (typically ) if any. # # The result when trying to set an encoding that is different # from the document encoding is undefined. # # Beware in CRuby, that libxml2 automatically inserts a meta tag # into a head element. def meta_encoding=(encoding) if (meta = meta_content_type) meta["content"] = format("text/html; charset=%s", encoding) encoding elsif (meta = at_xpath("//meta[@charset]")) meta["charset"] = encoding else meta = XML::Node.new("meta", self) if (dtd = internal_subset) && dtd.html5_dtd? meta["charset"] = encoding else meta["http-equiv"] = "Content-Type" meta["content"] = format("text/html; charset=%s", encoding) end if (head = at_xpath("//head")) head.prepend_child(meta) else set_metadata_element(meta) end encoding end end def meta_content_type xpath("//meta[@http-equiv and boolean(@content)]").find do |node| node["http-equiv"] =~ /\AContent-Type\z/i end end private :meta_content_type ### # Get the title string of this document. Return nil if there is # no title tag. def title (title = at_xpath("//title")) && title.inner_text end ### # Set the title string of this document. # # If a title element is already present, its content is replaced # with the given text. # # Otherwise, this method tries to create one at an appropriate # place supplying head and/or html elements as necessary, which # is inside a head element if any, right after a meta # encoding/charset tag if any, and before any text node or # content element (typically ) if any. def title=(text) tnode = XML::Text.new(text, self) if (title = at_xpath("//title")) title.children = tnode return text end title = XML::Node.new("title", self) << tnode if (head = at_xpath("//head")) head << title elsif (meta = (at_xpath("//meta[@charset]") || meta_content_type)) # better put after charset declaration meta.add_next_sibling(title) else set_metadata_element(title) end end def set_metadata_element(element) # rubocop:disable Naming/AccessorMethodName if (head = at_xpath("//head")) head << element elsif (html = at_xpath("//html")) head = html.prepend_child(XML::Node.new("head", self)) head.prepend_child(element) elsif (first = children.find do |node| case node when XML::Element, XML::Text true end end) # We reach here only if the underlying document model # allows / elements to be omitted and does not # automatically supply them. first.add_previous_sibling(element) else html = add_child(XML::Node.new("html", self)) head = html.add_child(XML::Node.new("head", self)) head.prepend_child(element) end end private :set_metadata_element #### # Serialize Node using +options+. Save options can also be set using a block. # # See also Nokogiri::XML::Node::SaveOptions and Node@Serialization+and+Generating+Output. # # These two statements are equivalent: # # node.serialize(:encoding => 'UTF-8', :save_with => FORMAT | AS_XML) # # or # # node.serialize(:encoding => 'UTF-8') do |config| # config.format.as_xml # end # def serialize(options = {}) options[:save_with] ||= XML::Node::SaveOptions::DEFAULT_HTML super end #### # Create a Nokogiri::XML::DocumentFragment from +tags+ def fragment(tags = nil) DocumentFragment.new(self, tags, root) end # :call-seq: # xpath_doctype() → Nokogiri::CSS::XPathVisitor::DoctypeConfig # # [Returns] The document type which determines CSS-to-XPath translation. # # See XPathVisitor for more information. def xpath_doctype Nokogiri::CSS::XPathVisitor::DoctypeConfig::HTML4 end class << self ### # Parse HTML. +string_or_io+ may be a String, or any object that # responds to _read_ and _close_ such as an IO, or StringIO. # +url+ is resource where this document is located. +encoding+ is the # encoding that should be used when processing the document. +options+ # is a number that sets options in the parser, such as # Nokogiri::XML::ParseOptions::RECOVER. See the constants in # Nokogiri::XML::ParseOptions. def parse(string_or_io, url = nil, encoding = nil, options = XML::ParseOptions::DEFAULT_HTML) options = Nokogiri::XML::ParseOptions.new(options) if Integer === options yield options if block_given? url ||= string_or_io.respond_to?(:path) ? string_or_io.path : nil if string_or_io.respond_to?(:encoding) unless string_or_io.encoding.name == "ASCII-8BIT" encoding ||= string_or_io.encoding.name end end if string_or_io.respond_to?(:read) if string_or_io.is_a?(Pathname) # resolve the Pathname to the file and open it as an IO object, see #2110 string_or_io = string_or_io.expand_path.open url ||= string_or_io.path end unless encoding # Libxml2's parser has poor support for encoding # detection. First, it does not recognize the HTML5 # style meta charset declaration. Secondly, even if it # successfully detects an encoding hint, it does not # re-decode or re-parse the preceding part which may be # garbled. # # EncodingReader aims to perform advanced encoding # detection beyond what Libxml2 does, and to emulate # rewinding of a stream and make Libxml2 redo parsing # from the start when an encoding hint is found. string_or_io = EncodingReader.new(string_or_io) begin return read_io(string_or_io, url, encoding, options.to_i) rescue EncodingFound => e encoding = e.found_encoding end end return read_io(string_or_io, url, encoding, options.to_i) end # read_memory pukes on empty docs if string_or_io.nil? || string_or_io.empty? return encoding ? new.tap { |i| i.encoding = encoding } : new end encoding ||= EncodingReader.detect_encoding(string_or_io) read_memory(string_or_io, url, encoding, options.to_i) end end class EncodingFound < StandardError # :nodoc: all attr_reader :found_encoding def initialize(encoding) @found_encoding = encoding super(format("encoding found: %s", encoding)) end end # :nodoc: all class EncodingReader class SAXHandler < Nokogiri::XML::SAX::Document attr_reader :encoding def initialize @encoding = nil super() end def start_element(name, attrs = []) return unless name == "meta" attr = Hash[attrs] (charset = attr["charset"]) && (@encoding = charset) (http_equiv = attr["http-equiv"]) && http_equiv.match(/\AContent-Type\z/i) && (content = attr["content"]) && (m = content.match(/;\s*charset\s*=\s*([\w-]+)/)) && (@encoding = m[1]) end end class JumpSAXHandler < SAXHandler def initialize(jumptag) @jumptag = jumptag super() end def start_element(name, attrs = []) super throw(@jumptag, @encoding) if @encoding throw(@jumptag, nil) if /\A(?:div|h1|img|p|br)\z/.match?(name) end end def self.detect_encoding(chunk) (m = chunk.match(/\A(<\?xml[ \t\r\n][^>]*>)/)) && (return Nokogiri.XML(m[1]).encoding) if Nokogiri.jruby? (m = chunk.match(/( 0 (rest = @io.read(len)) && ret << (rest) end if ret.empty? nil else ret end end end end end end