REXML::Parsers::BaseParser

Class

Using the Pull Parser

This API is experimental, and subject to change.

parser = PullParser.new( "<a>text<b att='val'/>txet</a>" )
while parser.has_next?
  res = parser.next
  puts res[1]['att'] if res.start_tag? and res[0] == 'b'
end

See the PullEvent class for information on the content of the results. The data is identical to the arguments passed for the various events to the StreamListener API.

Notice that:

parser = PullParser.new( "<a>BAD DOCUMENT" )
while parser.has_next?
  res = parser.next
  raise res[1] if res.error?
end

Nat Price gave me some good ideas for the API.

Constants

MISSING_ATTRIBUTE_QUOTES

These are patterns to identify common markup errors, to make the error messages more informative.

Attributes

source

Read

No documentation available

Class Methods

new( source )

lib/rexml/parsers/baseparser.rb View on GitHub

          
            # File tmp/rubies/ruby-2.4.10/lib/rexml/parsers/baseparser.rb, line 117
def initialize( source )
  self.stream = source
  @listeners = []
end

No documentation available

Instance Methods

has_next?

lib/rexml/parsers/baseparser.rb View on GitHub

          
            # File tmp/rubies/ruby-2.4.10/lib/rexml/parsers/baseparser.rb, line 153
def has_next?
  return !(@source.empty? and @stack.empty?)
end

Returns true if there are more events. Synonymous with !empty?

need_source_encoding_update?(xml_declaration_encoding)

lib/rexml/parsers/baseparser.rb View on GitHub

          
            # File tmp/rubies/ruby-2.4.10/lib/rexml/parsers/baseparser.rb, line 506
def need_source_encoding_update?(xml_declaration_encoding)
  return false if xml_declaration_encoding.nil?
  return false if /\AUTF-16\z/i =~ xml_declaration_encoding
  true
end

No documentation available

normalize( input, entities=nil, entity_filter=nil )

lib/rexml/parsers/baseparser.rb View on GitHub

          
            # File tmp/rubies/ruby-2.4.10/lib/rexml/parsers/baseparser.rb, line 460
def normalize( input, entities=nil, entity_filter=nil )
  copy = input.clone
  # Doing it like this rather than in a loop improves the speed
  copy.gsub!( EREFERENCE, '&amp;' )
  entities.each do |key, value|
    copy.gsub!( value, "&#{key};" ) unless entity_filter and
                                entity_filter.include?(entity)
  end if entities
  copy.gsub!( EREFERENCE, '&amp;' )
  DEFAULT_ENTITIES.each do |key, value|
    copy.gsub!( value[3], value[1] )
  end
  copy
end

Escapes all possible entities

peek(depth=0)

lib/rexml/parsers/baseparser.rb View on GitHub

          
            # File tmp/rubies/ruby-2.4.10/lib/rexml/parsers/baseparser.rb, line 169
def peek depth=0
  raise %Q[Illegal argument "#{depth}"] if depth < -1
  temp = []
  if depth == -1
    temp.push(pull()) until empty?
  else
    while @stack.size+temp.size < depth+1
      temp.push(pull())
    end
  end
  @stack += temp if temp.size > 0
  @stack[depth]
end

Peek at the depth event in the stack. The first element on the stack is at depth 0. If depth is -1, will parse to the end of the input stream and return the last event, which is always :end_document. Be aware that this causes the stream to be parsed up to the depth event, so you can effectively pre-parse the entire document (pull the entire thing into memory) using this method.

position

lib/rexml/parsers/baseparser.rb View on GitHub

          
            # File tmp/rubies/ruby-2.4.10/lib/rexml/parsers/baseparser.rb, line 138
def position
  if @source.respond_to? :position
    @source.position
  else
    # FIXME
    0
  end
end

No documentation available

pull

lib/rexml/parsers/baseparser.rb View on GitHub

          
            # File tmp/rubies/ruby-2.4.10/lib/rexml/parsers/baseparser.rb, line 184
def pull
  pull_event.tap do |event|
    @listeners.each do |listener|
      listener.receive event
    end
  end
end

Returns the next event. This is a PullEvent object.

pull_event

lib/rexml/parsers/baseparser.rb View on GitHub

          
            # File tmp/rubies/ruby-2.4.10/lib/rexml/parsers/baseparser.rb, line 192
def pull_event
  if @closed
    x, @closed = @closed, nil
    return [ :end_element, x ]
  end
  return [ :end_document ] if empty?
  return @stack.shift if @stack.size > 0
  #STDERR.puts @source.encoding
  @source.read if @source.buffer.size<2
  #STDERR.puts "BUFFER = #{@source.buffer.inspect}"
  if @document_status == nil
    #@source.consume( /^\s*/um )
    word = @source.match( /^((?:\s+)|(?:<[^>]*>))/um )
    word = word[1] unless word.nil?
    #STDERR.puts "WORD = #{word.inspect}"
    case word
    when COMMENT_START
      return [ :comment, @source.match( COMMENT_PATTERN, true )[1] ]
    when XMLDECL_START
      #STDERR.puts "XMLDECL"
      results = @source.match( XMLDECL_PATTERN, true )[1]
      version = VERSION.match( results )
      version = version[1] unless version.nil?
      encoding = ENCODING.match(results)
      encoding = encoding[1] unless encoding.nil?
      if need_source_encoding_update?(encoding)
        @source.encoding = encoding
      end
      if encoding.nil? and /\AUTF-16(?:BE|LE)\z/i =~ @source.encoding
        encoding = "UTF-16"
      end
      standalone = STANDALONE.match(results)
      standalone = standalone[1] unless standalone.nil?
      return [ :xmldecl, version, encoding, standalone ]
    when INSTRUCTION_START
      return [ :processing_instruction, *@source.match(INSTRUCTION_PATTERN, true)[1,2] ]
    when DOCTYPE_START
      md = @source.match( DOCTYPE_PATTERN, true )
      @nsstack.unshift(curr_ns=Set.new)
      identity = md[1]
      close = md[2]
      identity =~ IDENTITY
      name = $1
      raise REXML::ParseException.new("DOCTYPE is missing a name") if name.nil?
      pub_sys = $2.nil? ? nil : $2.strip
      long_name = $4.nil? ? nil : $4.strip
      uri = $6.nil? ? nil : $6.strip
      args = [ :start_doctype, name, pub_sys, long_name, uri ]
      if close == ">"
        @document_status = :after_doctype
        @source.read if @source.buffer.size<2
        md = @source.match(/^\s*/um, true)
        @stack << [ :end_doctype ]
      else
        @document_status = :in_doctype
      end
      return args
    when /^\s+/
    else
      @document_status = :after_doctype
      @source.read if @source.buffer.size<2
      md = @source.match(/\s*/um, true)
      if @source.encoding == "UTF-8"
        @source.buffer.force_encoding(::Encoding::UTF_8)
      end
    end
  end
  if @document_status == :in_doctype
    md = @source.match(/\s*(.*?>)/um)
    case md[1]
    when SYSTEMENTITY
      match = @source.match( SYSTEMENTITY, true )[1]
      return [ :externalentity, match ]

    when ELEMENTDECL_START
      return [ :elementdecl, @source.match( ELEMENTDECL_PATTERN, true )[1] ]

    when ENTITY_START
      match = @source.match( ENTITYDECL, true ).to_a.compact
      match[0] = :entitydecl
      ref = false
      if match[1] == '%'
        ref = true
        match.delete_at 1
      end
      # Now we have to sort out what kind of entity reference this is
      if match[2] == 'SYSTEM'
        # External reference
        match[3] = match[3][1..-2] # PUBID
        match.delete_at(4) if match.size > 4 # Chop out NDATA decl
        # match is [ :entity, name, SYSTEM, pubid(, ndata)? ]
      elsif match[2] == 'PUBLIC'
        # External reference
        match[3] = match[3][1..-2] # PUBID
        match[4] = match[4][1..-2] # HREF
        match.delete_at(5) if match.size > 5 # Chop out NDATA decl
        # match is [ :entity, name, PUBLIC, pubid, href(, ndata)? ]
      else
        match[2] = match[2][1..-2]
        match.pop if match.size == 4
        # match is [ :entity, name, value ]
      end
      match << '%' if ref
      return match
    when ATTLISTDECL_START
      md = @source.match( ATTLISTDECL_PATTERN, true )
      raise REXML::ParseException.new( "Bad ATTLIST declaration!", @source ) if md.nil?
      element = md[1]
      contents = md[0]

      pairs = {}
      values = md[0].scan( ATTDEF_RE )
      values.each do |attdef|
        unless attdef[3] == "#IMPLIED"
          attdef.compact!
          val = attdef[3]
          val = attdef[4] if val == "#FIXED "
          pairs[attdef[0]] = val
          if attdef[0] =~ /^xmlns:(.*)/
            @nsstack[0] << $1
          end
        end
      end
      return [ :attlistdecl, element, pairs, contents ]
    when NOTATIONDECL_START
      md = nil
      if @source.match( PUBLIC )
        md = @source.match( PUBLIC, true )
        vals = [md[1],md[2],md[4],md[6]]
      elsif @source.match( SYSTEM )
        md = @source.match( SYSTEM, true )
        vals = [md[1],md[2],nil,md[4]]
      else
        raise REXML::ParseException.new( "error parsing notation: no matching pattern", @source )
      end
      return [ :notationdecl, *vals ]
    when DOCTYPE_END
      @document_status = :after_doctype
      @source.match( DOCTYPE_END, true )
      return [ :end_doctype ]
    end
  end
  begin
    if @source.buffer[0] == ?<
      if @source.buffer[1] == ?/
        @nsstack.shift
        last_tag = @tags.pop
        #md = @source.match_to_consume( '>', CLOSE_MATCH)
        md = @source.match( CLOSE_MATCH, true )
        raise REXML::ParseException.new( "Missing end tag for "+
          "'#{last_tag}' (got \"#{md[1]}\")",
          @source) unless last_tag == md[1]
        return [ :end_element, last_tag ]
      elsif @source.buffer[1] == ?!
        md = @source.match(/\A(\s*[^>]*>)/um)
        #STDERR.puts "SOURCE BUFFER = #{source.buffer}, #{source.buffer.size}"
        raise REXML::ParseException.new("Malformed node", @source) unless md
        if md[0][2] == ?-
          md = @source.match( COMMENT_PATTERN, true )

          case md[1]
          when /--/, /-\z/
            raise REXML::ParseException.new("Malformed comment", @source)
          end

          return [ :comment, md[1] ] if md
        else
          md = @source.match( CDATA_PATTERN, true )
          return [ :cdata, md[1] ] if md
        end
        raise REXML::ParseException.new( "Declarations can only occur "+
          "in the doctype declaration.", @source)
      elsif @source.buffer[1] == ??
        md = @source.match( INSTRUCTION_PATTERN, true )
        return [ :processing_instruction, md[1], md[2] ] if md
        raise REXML::ParseException.new( "Bad instruction declaration",
          @source)
      else
        # Get the next tag
        md = @source.match(TAG_MATCH, true)
        unless md
          # Check for missing attribute quotes
          raise REXML::ParseException.new("missing attribute quote", @source) if @source.match(MISSING_ATTRIBUTE_QUOTES )
          raise REXML::ParseException.new("malformed XML: missing tag start", @source)
        end
        attributes = {}
        prefixes = Set.new
        prefixes << md[2] if md[2]
        @nsstack.unshift(curr_ns=Set.new)
        if md[4].size > 0
          attrs = md[4].scan( ATTRIBUTE_PATTERN )
          raise REXML::ParseException.new( "error parsing attributes: [#{attrs.join ', '}], excess = \"#$'\"", @source) if $' and $'.strip.size > 0
          attrs.each do |attr_name, prefix, local_part, quote, value|
            if prefix == "xmlns"
              if local_part == "xml"
                if value != "http://www.w3.org/XML/1998/namespace"
                  msg = "The 'xml' prefix must not be bound to any other namespace "+
                  "(http://www.w3.org/TR/REC-xml-names/#ns-decl)"
                  raise REXML::ParseException.new( msg, @source, self )
                end
              elsif local_part == "xmlns"
                msg = "The 'xmlns' prefix must not be declared "+
                "(http://www.w3.org/TR/REC-xml-names/#ns-decl)"
                raise REXML::ParseException.new( msg, @source, self)
              end
              curr_ns << local_part
            elsif prefix
              prefixes << prefix unless prefix == "xml"
            end

            if attributes.has_key?(attr_name)
              msg = "Duplicate attribute #{attr_name.inspect}"
              raise REXML::ParseException.new(msg, @source, self)
            end

            attributes[attr_name] = value
          end
        end

        # Verify that all of the prefixes have been defined
        for prefix in prefixes
          unless @nsstack.find{|k| k.member?(prefix)}
            raise UndefinedNamespaceException.new(prefix,@source,self)
          end
        end

        if md[6]
          @closed = md[1]
          @nsstack.shift
        else
          @tags.push( md[1] )
        end
        return [ :start_element, md[1], attributes ]
      end
    else
      md = @source.match( TEXT_PATTERN, true )
      if md[0].length == 0
        @source.match( /(\s+)/, true )
      end
      #STDERR.puts "GOT #{md[1].inspect}" unless md[0].length == 0
      #return [ :text, "" ] if md[0].length == 0
      # unnormalized = Text::unnormalize( md[1], self )
      # return PullEvent.new( :text, md[1], unnormalized )
      return [ :text, md[1] ]
    end
  rescue REXML::UndefinedNamespaceException
    raise
  rescue REXML::ParseException
    raise
  rescue Exception, NameError => error
    raise REXML::ParseException.new( "Exception parsing",
      @source, self, (error ? error : $!) )
  end
  return [ :dummy ]
end

No documentation available

stream=( source )

lib/rexml/parsers/baseparser.rb View on GitHub

          
            # File tmp/rubies/ruby-2.4.10/lib/rexml/parsers/baseparser.rb, line 128
def stream=( source )
  @source = SourceFactory.create_from( source )
  @closed = nil
  @document_status = nil
  @tags = []
  @stack = []
  @entities = []
  @nsstack = []
end

No documentation available

unnormalize( string, entities=nil, filter=nil )

lib/rexml/parsers/baseparser.rb View on GitHub

          
            # File tmp/rubies/ruby-2.4.10/lib/rexml/parsers/baseparser.rb, line 476
def unnormalize( string, entities=nil, filter=nil )
  rv = string.clone
  rv.gsub!( /\r\n?/, "\n" )
  matches = rv.scan( REFERENCE_RE )
  return rv if matches.size == 0
  rv.gsub!( /&#0*((?:\d+)|(?:x[a-fA-F0-9]+));/ ) {
    m=$1
    m = "0#{m}" if m[0] == ?x
    [Integer(m)].pack('U*')
  }
  matches.collect!{|x|x[0]}.compact!
  if matches.size > 0
    matches.each do |entity_reference|
      unless filter and filter.include?(entity_reference)
        entity_value = entity( entity_reference, entities )
        if entity_value
          re = /&#{entity_reference};/
          rv.gsub!( re, entity_value )
        else
          er = DEFAULT_ENTITIES[entity_reference]
          rv.gsub!( er[0], er[2] ) if er
        end
      end
    end
    rv.gsub!( /&amp;/, '&' )
  end
  rv
end

Unescapes all possible entities

unshift(token)

lib/rexml/parsers/baseparser.rb View on GitHub

          
            # File tmp/rubies/ruby-2.4.10/lib/rexml/parsers/baseparser.rb, line 159
def unshift token
  @stack.unshift(token)
end

Push an event back on the head of the stream. This method has (theoretically) infinite depth.

Using the Pull Parser

new( source )

add_listener( listener )

empty?

entity( reference, entities )

has_next?

need_source_encoding_update?(xml_declaration_encoding)

normalize( input, entities=nil, entity_filter=nil )

peek(depth=0)

position

pull

pull_event

stream=( source )

unnormalize( string, entities=nil, filter=nil )

unshift(token)