Class: Nokogiri::HTML::Document

Inherits:
XML::Document show all
Defined in:
lib/nokogiri/html/document.rb,
ext/nokogiri/html_document.c

Defined Under Namespace

Classes: EncodingFound, EncodingReader

Class Method Summary collapse

Instance Method Summary collapse

Constructor Details

This class inherits a constructor from Nokogiri::XML::Document

Class Method Details

.newObject

Create a new document


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# File 'ext/nokogiri/html_document.c', line 12

static VALUE
rb_html_document_s_new(int argc, VALUE *argv, VALUE klass)
{
  VALUE uri, external_id, rest, rb_doc;
  htmlDocPtr doc;

  rb_scan_args(argc, argv, "0*", &rest);
  uri = rb_ary_entry(rest, (long)0);
  external_id = rb_ary_entry(rest, (long)1);

  doc = htmlNewDoc(
          RTEST(uri) ? (const xmlChar *)StringValueCStr(uri) : NULL,
          RTEST(external_id) ? (const xmlChar *)StringValueCStr(external_id) : NULL
        );
  rb_doc = nokogiri_xml_document_wrap_with_init_args(klass, doc, argc, argv);
  return rb_doc ;
}

.parse(string_or_io, url = nil, encoding = nil, options = XML::ParseOptions::DEFAULT_HTML) {|options| ... } ⇒ Object

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.

Yields:

  • (options)

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# File 'lib/nokogiri/html/document.rb', line 166

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? or 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

.read_io(io, url, encoding, options) ⇒ Object

Read the HTML document from io with given url, encoding, and options. See Nokogiri::HTML.parse


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# File 'ext/nokogiri/html_document.c', line 37

static VALUE
rb_html_document_s_read_io(VALUE klass, VALUE rb_io, VALUE rb_url, VALUE rb_encoding, VALUE rb_options)
{
  VALUE rb_doc;
  VALUE rb_error_list = rb_ary_new();
  htmlDocPtr c_doc;
  const char *c_url = NIL_P(rb_url) ? NULL : StringValueCStr(rb_url);
  const char *c_encoding = NIL_P(rb_encoding) ? NULL : StringValueCStr(rb_encoding);
  int options = NUM2INT(rb_options);

  xmlSetStructuredErrorFunc((void *)rb_error_list, Nokogiri_error_array_pusher);

  c_doc = htmlReadIO(io_read_callback, io_close_callback, (void *)rb_io, c_url, c_encoding, options);

  xmlSetStructuredErrorFunc(NULL, NULL);

  /*
   * If EncodingFound has occurred in EncodingReader, make sure to do
   * a cleanup and propagate the error.
   */
  if (rb_respond_to(rb_io, id_encoding_found)) {
    VALUE encoding_found = rb_funcall(rb_io, id_encoding_found, 0);
    if (!NIL_P(encoding_found)) {
      xmlFreeDoc(c_doc);
      rb_exc_raise(encoding_found);
    }
  }

  if ((c_doc == NULL) || (!(options & XML_PARSE_RECOVER) && (RARRAY_LEN(rb_error_list) > 0))) {
    VALUE rb_error ;

    xmlFreeDoc(c_doc);

    rb_error = rb_ary_entry(rb_error_list, 0);
    if (rb_error == Qnil) {
      rb_raise(rb_eRuntimeError, "Could not parse document");
    } else {
      VALUE exception_message = rb_funcall(rb_error, id_to_s, 0);
      exception_message = rb_str_concat(rb_str_new2("Parser without recover option encountered error or warning: "),
                                        exception_message);
      rb_exc_raise(rb_class_new_instance(1, &exception_message, cNokogiriXmlSyntaxError));
    }

    return Qnil;
  }

  rb_doc = nokogiri_xml_document_wrap(klass, c_doc);
  rb_iv_set(rb_doc, "@errors", rb_error_list);
  return rb_doc;
}

.read_memory(string, url, encoding, options) ⇒ Object

Read the HTML document contained in string with given url, encoding, and options. See Nokogiri::HTML.parse


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# File 'ext/nokogiri/html_document.c', line 95

static VALUE
rb_html_document_s_read_memory(VALUE klass, VALUE rb_html, VALUE rb_url, VALUE rb_encoding, VALUE rb_options)
{
  VALUE rb_doc;
  VALUE rb_error_list = rb_ary_new();
  htmlDocPtr c_doc;
  const char *c_buffer = StringValuePtr(rb_html);
  const char *c_url = NIL_P(rb_url) ? NULL : StringValueCStr(rb_url);
  const char *c_encoding = NIL_P(rb_encoding) ? NULL : StringValueCStr(rb_encoding);
  int html_len = (int)RSTRING_LEN(rb_html);
  int options = NUM2INT(rb_options);

  xmlSetStructuredErrorFunc((void *)rb_error_list, Nokogiri_error_array_pusher);

  c_doc = htmlReadMemory(c_buffer, html_len, c_url, c_encoding, options);

  xmlSetStructuredErrorFunc(NULL, NULL);

  if ((c_doc == NULL) || (!(options & XML_PARSE_RECOVER) && (RARRAY_LEN(rb_error_list) > 0))) {
    VALUE rb_error ;

    xmlFreeDoc(c_doc);

    rb_error = rb_ary_entry(rb_error_list, 0);
    if (rb_error == Qnil) {
      rb_raise(rb_eRuntimeError, "Could not parse document");
    } else {
      VALUE exception_message = rb_funcall(rb_error, id_to_s, 0);
      exception_message = rb_str_concat(rb_str_new2("Parser without recover option encountered error or warning: "),
                                        exception_message);
      rb_exc_raise(rb_class_new_instance(1, &exception_message, cNokogiriXmlSyntaxError));
    }

    return Qnil;
  }

  rb_doc = nokogiri_xml_document_wrap(klass, c_doc);
  rb_iv_set(rb_doc, "@errors", rb_error_list);
  return rb_doc;
}

Instance Method Details

#fragment(tags = nil) ⇒ Object

Create a Nokogiri::XML::DocumentFragment from tags


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# File 'lib/nokogiri/html/document.rb', line 153

def fragment tags = nil
  DocumentFragment.new(self, tags, self.root)
end

#meta_encodingObject

Get the meta tag encoding for this document. If there is no meta tag, then nil is returned.


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# File 'lib/nokogiri/html/document.rb', line 11

def meta_encoding
  case
  when meta = at('//meta[@charset]')
    meta[:charset]
  when meta = meta_content_type
    meta['content'][/charset\s*=\s*([\w-]+)/i, 1]
  end
end

#meta_encoding=(encoding) ⇒ Object

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 <body>) 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.


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# File 'lib/nokogiri/html/document.rb', line 36

def meta_encoding= encoding
  case
  when meta = meta_content_type
    meta['content'] = 'text/html; charset=%s' % encoding
    encoding
  when meta = at('//meta[@charset]')
    meta['charset'] = encoding
  else
    meta = XML::Node.new('meta', self)
    if dtd = internal_subset and dtd.html5_dtd?
      meta['charset'] = encoding
    else
      meta['http-equiv'] = 'Content-Type'
      meta['content'] = 'text/html; charset=%s' % encoding
    end

    case
    when head = at('//head')
      head.prepend_child(meta)
    else
      (meta)
    end
    encoding
  end
end

#serialize(options = {}) ⇒ Object

Serialize Node using options. Save options can also be set using a block. See SaveOptions.

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

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# File 'lib/nokogiri/html/document.rb', line 146

def serialize options = {}
  options[:save_with] ||= XML::Node::SaveOptions::DEFAULT_HTML
  super
end

#titleObject

Get the title string of this document. Return nil if there is no title tag.


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# File 'lib/nokogiri/html/document.rb', line 72

def title
  title = at('//title') and title.inner_text
end

#title=(text) ⇒ Object

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 <body>) if any.


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# File 'lib/nokogiri/html/document.rb', line 87

def title=(text)
  tnode = XML::Text.new(text, self)
  if title = at('//title')
    title.children = tnode
    return text
  end

  title = XML::Node.new('title', self) << tnode
  case
  when head = at('//head')
    head << title
  when meta = at('//meta[@charset]') || meta_content_type
    # better put after charset declaration
    meta.add_next_sibling(title)
  else
    (title)
  end
  text
end

#typeObject

The type for this document


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# File 'ext/nokogiri/html_document.c', line 142

static VALUE
rb_html_document_type(VALUE self)
{
  htmlDocPtr doc;
  Data_Get_Struct(self, xmlDoc, doc);
  return INT2NUM((long)doc->type);
}