Class: REXML::Document

Relationships & Source Files
Super Chains via Extension / Inclusion / Inheritance
Class Chain: self, `Element`, `Parent`, `Child`
Instance Chain: self, `Element`, `Namespace`, `XMLTokens`, `Parent`, Enumerable, `Child`, `Node`
Inherits:	REXML::Element Object REXML::Child REXML::Parent REXML::Element REXML::Document
Defined in:	lib/rexml/document.rb

Overview

Represents an XML document.

A document may have:

A single child that may be accessed via method #root.
An XML declaration.
A document type.
Processing instructions.

In a Hurry?

If you’re somewhat familiar with XML and have a particular task in mind, you may want to see the tasks pages, and in particular, the tasks page for documents.

Constant Summary

DECLARATION =
A convenient default XML declaration. Use:
```
mydoc << XMLDecl.default
```
# File 'lib/rexml/document.rb', line 40
```
XMLDecl.default
```

`XMLTokens` - Included

NAME, NAMECHAR, NAME_CHAR, NAME_START_CHAR, NAME_STR, NCNAME_STR, NMTOKEN, NMTOKENS, REFERENCE

`Element` - Inherited

UNDEFINED

Class Attribute Summary

.entity_expansion_limit rw

Get the entity expansion limit.
.entity_expansion_limit=(val) rw

Set the entity expansion limit.
.entity_expansion_text_limit rw

Get the entity expansion limit.
.entity_expansion_text_limit=(val) rw

Set the entity expansion limit.

Class Method Summary

.new(string = nil, context = {}) ⇒ Document constructor

Returns a new REXML::Document object.
.parse_stream(source, listener)

`Element` - Inherited

.new	Returns a new REXML::Element object.

`Parent` - Inherited

.new	Constructor.

`Child` - Inherited

.new	Constructor.

Instance Attribute Summary

#entity_expansion_count readonly
#entity_expansion_limit=(value) writeonly
#entity_expansion_text_limit rw
#stand_alone? ⇒ Boolean readonly

Returns the XMLDecl standalone value of the document as a string, if it has been set, otherwise the default standalone value:

`Element` - Inherited

#attributes	Mechanisms for accessing attributes and child elements of this element.
#context	The context holds information about the processing environment, such as whitespace handling.
#elements	Mechanisms for accessing attributes and child elements of this element.
#has_attributes?	Returns `true` if the element has attributes, `false` otherwise:
#has_elements?	Returns `true` if the element has one or more element children, `false` otherwise:
#has_text?	Returns `true` if the element has one or more text noded, `false` otherwise:

`Namespace` - Included

#expanded_name	The name of the object, valid if set.
#local_name	Alias for Namespace#name.
#name	The name of the object, valid if set.
#name=	Sets the name and the expanded name.
#prefix	The expanded name of the object, valid if name is set.

`Parent` - Inherited

#parent?

`Child` - Inherited

#next_sibling	Alias for Node#next_sibling_node.
#next_sibling=	Sets the next sibling of this child.
#parent	The Parent of this object.
#parent=	Sets the parent of this child to the supplied argument.
#previous_sibling	Alias for Node#previous_sibling_node.
#previous_sibling=	Sets the previous sibling of this child.

`Node` - Included

#parent?

Instance Method Summary

#<<(child)

Alias for #add.
#add(xml_decl) ⇒ self (also: #<<)

Adds an object to the document; returns self.
#add_element(name_or_element = nil, attributes = nil) ⇒ new_element

Adds an element to the document by calling REXML::Element.add_element:
#clone ⇒ Document

Returns the new document resulting from executing Document.new(self).
#doctype ⇒ doc_type^?

Returns the DocType object for the document, if it exists, otherwise nil:
#document
#encoding ⇒ encoding_string

Returns the XMLDecl encoding of the document, if it has been set, otherwise the default encoding:
#expanded_name ⇒ empty_string (also: #name)

Returns an empty string.
#name

Alias for #expanded_name.
#node_type ⇒ Document

Returns the symbol :document.
#record_entity_expansion
#root ⇒ root_element^?

Returns the root element of the document, if it exists, otherwise nil:
#version ⇒ version_string

Returns the XMLDecl version of this document as a string, if it has been set, otherwise the default version:
#write(output = $stdout, indent = -1, transtive = false, ie_hack = false, encoding = nil)

Write the XML tree out, optionally with indent.
#xml_decl ⇒ xml_decl

Returns the XMLDecl object for the document, if it exists, otherwise the default XMLDecl object:
#build(source) private

`Element` - Inherited

#[]	With integer argument `index` given, returns the child at offset `index`, or `nil` if none:
#add_attribute	Adds an attribute to this element, overwriting any existing attribute by the same name.
#add_attributes	Adds zero or more attributes to the element; returns the argument.
#add_element	Adds a child element, optionally setting attributes on the added element; returns the added element.
#add_namespace	Adds a namespace to the element; returns `self`.
#add_text	Adds text to the element.
#attribute	Returns the string value for the given attribute name.
#cdatas	Returns a frozen array of the `CData` children of the element:
#clone	Returns a shallow copy of the element, containing the name and attributes, but not the parent or children:
#comments	Returns a frozen array of the `Comment` children of the element:
#delete_attribute	Removes a named attribute if it exists; returns the removed attribute if found, otherwise `nil`:
#delete_element	Deletes a child element.
#delete_namespace	Removes a namespace from the element.
#document	If the element is part of a document, returns that document:
#each_element	Calls the given block with each child element:
#each_element_with_attribute	Calls the given block with each child element that meets given criteria.
#each_element_with_text	Calls the given block with each child element that meets given criteria.
#get_elements	Returns an array of the elements that match the given `xpath`:
#get_text	Returns the first text node child in a specified element, if it exists, `nil` otherwise.
#ignore_whitespace_nodes	Returns `true` if whitespace nodes are ignored for the element.
#inspect	Returns a string representation of the element.
#instructions	Returns a frozen array of the `Instruction` children of the element:
#namespace	Returns the string namespace URI for the element, possibly deriving from one of its ancestors.
#namespaces	Returns a hash of all defined namespaces in the element and its ancestors:
#next_element	Returns the next sibling that is an element if it exists, `niL` otherwise:
#node_type	Returns symbol `:element`:
#prefixes	Returns an array of the string prefixes (names) of all defined namespaces in the element and its ancestors:
#previous_element	Returns the previous sibling that is an element if it exists, `niL` otherwise:
#raw	Returns `true` if raw mode is set for the element.
#root	Returns the most distant element (not document) ancestor of the element:
#root_node	Returns the most distant ancestor of `self`.
#text	Returns the text string from the first text node child in a specified element, if it exists, `nil` otherwise.
#text=	Adds, replaces, or removes the first text node child in the element.
#texts	Returns a frozen array of the `Text` children of the element:
#whitespace	Returns `true` if whitespace is respected for this element, `false` otherwise.
#write	DEPRECATED See `Formatters`
#xpath	Returns the string xpath to the element relative to the most distant parent:
#__to_xpath_helper,
#each_with_something	A private helper method.

`Namespace` - Included

#fully_expanded_name	Fully expand the name, even if the prefix wasn’t specified in the source file.
#has_name?	Compares names optionally WITH namespaces.

`Parent` - Inherited

#<<	Alias for Parent#push.
#[]	Fetches a child at a given index.
#[]=	Set an index entry.
#add,
#children	Alias for Parent#to_a.
#deep_clone	Deeply clones this object.
#delete, #delete_at, #delete_if, #each,
#each_child	Alias for Parent#each.
#each_index,
#index	Fetches the index of a given child of this parent.
#insert_after	Inserts an child after another child child2 will be inserted after child1 in the child list of the parent.
#insert_before	Inserts an child before another child child2 will be inserted before child1 in the child list of the parent.
#length	Alias for Parent#size.
#push	Alias for Parent#add.
#replace_child	Replaces one child with another, making sure the nodelist is correct `Child`).
#size, #to_a, #unshift

`Child` - Inherited

#bytes	This doesn’t yet handle encodings.
#document	Returns the document this child belongs to, or nil if this child belongs to no document.
#remove	Removes this child from the parent.
#replace_with	Replaces this object with another object.

`Node` - Included

#each_recursive	Visit all subnodes of `self` recursively.
#find_first_recursive	Find (and return) first subnode (recursively) for which the block evaluates to true.
#indent,
#index_in_parent	Returns the position that `self` holds in its parent’s array, indexed from 1.
#next_sibling_node, #previous_sibling_node,
#to_s	indent

Constructor Details

.new(string = nil, context = {}) ⇒ `Document` .new(io_stream = nil, context = {}) ⇒ `Document` .new(document = nil, context = {}) ⇒ `Document`

Returns a new REXML::Document object.

When no arguments are given, returns an empty document:

d = REXML::Document.new
d.to_s # => ""

When argument string is given, it must be a string containing a valid XML document:

xml_string = '<root><foo>Foo</foo><bar>Bar</bar></root>'
d = REXML::Document.new(xml_string)
d.to_s # => "<root><foo>Foo</foo><bar>Bar</bar></root>"

When argument io_stream is given, it must be an IO object that is opened for reading, and when read must return a valid XML document:

File.write('t.xml', xml_string)
d = File.open('t.xml', 'r') do |io|
  REXML::Document.new(io)
end
d.to_s # => "<root><foo>Foo</foo><bar>Bar</bar></root>"

When argument #document is given, it must be an existing document object, whose context and attributes (but not children) are cloned into the new document:

d = REXML::Document.new(xml_string)
d.children    # => [<root> ... </>]
d.context = {raw: :all, compress_whitespace: :all}
d.add_attributes({'bar' => 0, 'baz' => 1})
d1 = REXML::Document.new(d)
d1.children   # => []
d1.context    # => {:raw=>:all, :compress_whitespace=>:all}
d1.attributes # => {"bar"=>bar='0', "baz"=>baz='1'}

When argument context is given, it must be a hash containing context entries for the document; see {REXML::Element Context}:

context = {raw: :all, compress_whitespace: :all}
d = REXML::Document.new(xml_string, context)
d.context # => {:raw=>:all, :compress_whitespace=>:all}

[ GitHub ]

# File 'lib/rexml/document.rb', line 92


def initialize( source = nil, context = {} )
  @entity_expansion_count = 0
  @entity_expansion_limit = Security.entity_expansion_limit
  @entity_expansion_text_limit = Security.entity_expansion_text_limit
  super()
  @context = context
  return if source.nil?
  if source.kind_of? Document
    @context = source.context
    super source
  else
    build(  source )
  end
end

Class Attribute Details

.entity_expansion_limit (rw)

Get the entity expansion limit. By default the limit is set to 10000.

Deprecated. Use Security.entity_expansion_limit= instead.

[ GitHub ]

# File 'lib/rexml/document.rb', line 417


def Document::entity_expansion_limit
  return Security.entity_expansion_limit
end

.entity_expansion_limit=(val) (rw)

Set the entity expansion limit. By default the limit is set to 10000.

Deprecated. Use Security.entity_expansion_limit= instead.

[ GitHub ]

# File 'lib/rexml/document.rb', line 410


def Document::entity_expansion_limit=( val )
  Security.entity_expansion_limit = val
end

.entity_expansion_text_limit (rw)

Get the entity expansion limit. By default the limit is set to 10240.

Deprecated. Use Security.entity_expansion_text_limit instead.

[ GitHub ]

# File 'lib/rexml/document.rb', line 431


def Document::entity_expansion_text_limit
  return Security.entity_expansion_text_limit
end

.entity_expansion_text_limit=(val) (rw)

Set the entity expansion limit. By default the limit is set to 10240.

Deprecated. Use Security.entity_expansion_text_limit= instead.

[ GitHub ]

# File 'lib/rexml/document.rb', line 424


def Document::entity_expansion_text_limit=( val )
  Security.entity_expansion_text_limit = val
end

Class Method Details

.parse_stream(source, listener)

[ GitHub ]

# File 'lib/rexml/document.rb', line 403


def Document::parse_stream( source, listener )
  Parsers::StreamParser.new( source, listener ).parse
end

Instance Attribute Details

#entity_expansion_count (readonly)

[ GitHub ]

# File 'lib/rexml/document.rb', line 435


attr_reader :entity_expansion_count

#entity_expansion_limit=(value) (writeonly)

[ GitHub ]

# File 'lib/rexml/document.rb', line 436


attr_writer :entity_expansion_limit

#entity_expansion_text_limit (rw)

[ GitHub ]

# File 'lib/rexml/document.rb', line 437


attr_accessor :entity_expansion_text_limit

#stand_alone? ⇒ `Boolean` (readonly)

Returns the XMLDecl standalone value of the document as a string, if it has been set, otherwise the default standalone value:

d = REXML::Document.new('<?xml standalone="yes"?>')
d.stand_alone? # => "yes"
d = REXML::Document.new('')
d.stand_alone? # => nil

[ GitHub ]

# File 'lib/rexml/document.rb', line 307


def stand_alone?
  xml_decl().stand_alone?
end

Instance Method Details

#<<(child)

Alias for #add.

[ GitHub ]

# File 'lib/rexml/document.rb', line 203


alias :<< :add

#add(xml_decl) ⇒ `self` #add(doc_type) ⇒ `self` #add(object) ⇒ `self`
Also known as: #<<

Adds an object to the document; returns self.

When argument #xml_decl is given, it must be an XMLDecl object, which becomes the XML declaration for the document, replacing the previous XML declaration if any:

d = REXML::Document.new
d.xml_decl.to_s # => ""
d.add(REXML::XMLDecl.new('2.0'))
d.xml_decl.to_s # => "<?xml version='2.0'?>"

When argument doc_type is given, it must be an DocType object, which becomes the document type for the document, replacing the previous document type, if any:

d = REXML::Document.new
d.doctype.to_s # => ""
d.add(REXML::DocType.new('foo'))
d.doctype.to_s # => "<!DOCTYPE foo>"

When argument object (not an XMLDecl or DocType object) is given it is added as the last child:

d = REXML::Document.new
d.add(REXML::Element.new('foo'))
d.to_s # => "<foo/>"

[ GitHub ]

# File 'lib/rexml/document.rb', line 172


def add( child )
  if child.kind_of? XMLDecl
    if @children[0].kind_of? XMLDecl
      @children[0] = child
    else
      @children.unshift child
    end
    child.parent = self
  elsif child.kind_of? DocType
    # Find first Element or DocType node and insert the decl right
    # before it.  If there is no such node, just insert the child at the
    # end.  If there is a child and it is an DocType, then replace it.
    insert_before_index = @children.find_index { |x|
      x.kind_of?(Element) || x.kind_of?(DocType)
    }
    if insert_before_index # Not null = not end of list
      if @children[ insert_before_index ].kind_of? DocType
        @children[ insert_before_index ] = child
      else
        @children[ insert_before_index-1, 0 ] = child
      end
    else  # Insert at end of list
      @children << child
    end
    child.parent = self
  else
    rv = super
    raise "attempted adding second root element to document" if @elements.size > 1
    rv
  end
end

#add_element(name_or_element = nil, attributes = nil) ⇒ `new_element`

Adds an element to the document by calling REXML::Element.add_element:

REXML::Element.add_element(name_or_element, attributes)

[ GitHub ]

# File 'lib/rexml/document.rb', line 211


def add_element(arg=nil, arg2=nil)
  rv = super
  raise "attempted adding second root element to document" if @elements.size > 1
  rv
end

#build(source) (private)

[ GitHub ]

# File 'lib/rexml/document.rb', line 451


def build( source )
  Parsers::TreeParser.new( source, self ).parse
end

#clone ⇒ `Document`

Returns the new document resulting from executing Document.new(self). See .new.

[ GitHub ]

# File 'lib/rexml/document.rb', line 122


def clone
  Document.new self
end

#doctype ⇒ `doc_type`^?

Returns the DocType object for the document, if it exists, otherwise nil:

d = REXML::Document.new('<!DOCTYPE document SYSTEM "subjects.dtd">')
d.doctype.class # => REXML::DocType
d = REXML::Document.new('')
d.doctype.class # => nil

[ GitHub ]

# File 'lib/rexml/document.rb', line 243


def doctype
  @children.find { |item| item.kind_of? DocType }
end

#document

[ GitHub ]

# File 'lib/rexml/document.rb', line 446


def document
  self
end

#encoding ⇒ `encoding_string`

Returns the XMLDecl encoding of the document, if it has been set, otherwise the default encoding:

d = REXML::Document.new('<?xml version="1.0" encoding="UTF-16"?>')
d.encoding # => "UTF-16"
d = REXML::Document.new('')
d.encoding # => "UTF-8"

[ GitHub ]

# File 'lib/rexml/document.rb', line 292


def encoding
  xml_decl().encoding
end

#expanded_name ⇒ `empty_string` Also known as: #name

Returns an empty string.

[ GitHub ]

# File 'lib/rexml/document.rb', line 131


def expanded_name
  ''
  #d = doc_type
  #d ? d.name : "UNDEFINED"
end

#name

Alias for #expanded_name.

[ GitHub ]

# File 'lib/rexml/document.rb', line 136


alias :name :expanded_name

#node_type ⇒ `Document`

Returns the symbol :document.

[ GitHub ]

# File 'lib/rexml/document.rb', line 112


def node_type
  :document
end

#record_entity_expansion

[ GitHub ]

# File 'lib/rexml/document.rb', line 439


def record_entity_expansion
  @entity_expansion_count += 1
  if @entity_expansion_count > @entity_expansion_limit
    raise "number of entity expansions exceeded, processing aborted."
  end
end

#root ⇒ `root_element`^?

Returns the root element of the document, if it exists, otherwise nil:

d = REXML::Document.new('<root></root>')
d.root # => <root/>
d = REXML::Document.new('')
d.root # => nil

[ GitHub ]

# File 'lib/rexml/document.rb', line 227


def root
  elements[1]
  #self
  #@children.find { |item| item.kind_of? Element }
end

#version ⇒ `version_string`

Returns the XMLDecl version of this document as a string, if it has been set, otherwise the default version:

d = REXML::Document.new('<?xml version="2.0" encoding="UTF-8"?>')
d.version # => "2.0"
d = REXML::Document.new('')
d.version # => "1.0"

[ GitHub ]

# File 'lib/rexml/document.rb', line 277


def version
  xml_decl().version
end

#write(output = $stdout, indent = -1, transtive = false, ie_hack = false, encoding = nil) #write(options={:output) ⇒ $`stdout`, `:indent`

Write the XML tree out, optionally with indent. This writes out the entire XML document, including XML declarations, doctype declarations, and processing instructions (if any are given).

A controversial point is whether Document should always write the XML declaration (<?xml version=‘1.0’?>) whether or not one is given by the user (or source document). ::REXML does not write one if one was not specified, because it adds unnecessary bandwidth to applications such as XML-RPC.

Accept Nth argument style and options Hash style as argument. The recommended style is options Hash style for one or more arguments case.

Examples

Document.new("<a><b/></a>").write

output = ""
Document.new("<a><b/></a>").write(output)

output = ""
Document.new("<a><b/></a>").write(:output => output, :indent => 2)

See also the classes in the rexml/formatters package for the proper way to change the default formatting of XML output.

Examples

output = ""
tr = Transitive.new
tr.write(Document.new("<a><b/></a>"), output)

output: output an object which supports ‘<< string’; this is where the document will be written.
indent: An integer. If -1, no indenting will be used; otherwise, the indentation will be twice this number of spaces, and children will be indented an additional amount. For a value of 3, every item will be indented 3 more levels, or 6 more spaces (2 * 3). Defaults to -1
transitive: If transitive is true and indent is >= 0, then the output will be pretty-printed in such a way that the added whitespace does not affect the absolute value of the document – that is, it leaves the value and number of Text nodes in the document unchanged.
ie_hack: This hack inserts a space before the /> on empty tags to address a limitation of Internet Explorer. Defaults to false
encoding: Encoding name as String. Change output encoding to specified encoding instead of encoding in XML declaration. Defaults to nil. It means encoding in XML declaration is used.

[ GitHub ]

# File 'lib/rexml/document.rb', line 367


def write(*arguments)
  if arguments.size == 1 and arguments[0].class == Hash
    options = arguments[0]

    output     = options[:output]
    indent     = options[:indent]
    transitive = options[:transitive]
    ie_hack    = options[:ie_hack]
    encoding   = options[:encoding]
  else
    output, indent, transitive, ie_hack, encoding, = *arguments
  end

  output   ||= $stdout
  indent   ||= -1
  transitive = false if transitive.nil?
  ie_hack    = false if ie_hack.nil?
  encoding ||= xml_decl.encoding

  if encoding != 'UTF-8' && !output.kind_of?(Output)
    output = Output.new( output, encoding )
  end
  formatter = if indent > -1
      if transitive
        require_relative "formatters/transitive"
        REXML::Formatters::Transitive.new( indent, ie_hack )
      else
        REXML::Formatters::Pretty.new( indent, ie_hack )
      end
    else
      REXML::Formatters::Default.new( ie_hack )
    end
  formatter.write( self, output )
end

#xml_decl ⇒ xml_decl

Returns the XMLDecl object for the document, if it exists, otherwise the default XMLDecl object:

d = REXML::Document.new('<?xml version="1.0" encoding="UTF-8"?>')
d.xml_decl.class # => REXML::XMLDecl
d.xml_decl.to_s  # => "<?xml version='1.0' encoding='UTF-8'?>"
d = REXML::Document.new('')
d.xml_decl.class # => REXML::XMLDecl
d.xml_decl.to_s  # => ""

[ GitHub ]

# File 'lib/rexml/document.rb', line 260


def xml_decl
  rv = @children[0]
  return rv if rv.kind_of? XMLDecl
  @children.unshift(XMLDecl.default)[0]
end

Class: REXML::Document

Overview

In a Hurry?

Constant Summary

XMLTokens - Included

Namespace - Included

Element - Inherited

Class Attribute Summary

Class Method Summary

Element - Inherited

Parent - Inherited

Child - Inherited

Instance Attribute Summary

Element - Inherited

Namespace - Included

Parent - Inherited

Child - Inherited

Node - Included

Instance Method Summary

Element - Inherited

Namespace - Included

Parent - Inherited

Child - Inherited

Node - Included

Constructor Details

.new(string = nil, context = {}) ⇒ Document .new(io_stream = nil, context = {}) ⇒ Document .new(document = nil, context = {}) ⇒ Document

Class Attribute Details

.entity_expansion_limit (rw)

.entity_expansion_limit=(val) (rw)

.entity_expansion_text_limit (rw)

.entity_expansion_text_limit=(val) (rw)

Class Method Details

.parse_stream(source, listener)

Instance Attribute Details

#entity_expansion_count (readonly)

#entity_expansion_limit=(value) (writeonly)

#entity_expansion_text_limit (rw)

#stand_alone? ⇒ Boolean (readonly)

Instance Method Details

#<<(child)

#add(xml_decl) ⇒ self #add(doc_type) ⇒ self #add(object) ⇒ self Also known as: #<<

#add_element(name_or_element = nil, attributes = nil) ⇒ new_element

#build(source) (private)

#clone ⇒ Document

#doctype ⇒ doc_type?

#document

#encoding ⇒ encoding_string

#expanded_name ⇒ empty_string Also known as: #name

#name

#node_type ⇒ Document

#record_entity_expansion

#root ⇒ root_element?

#version ⇒ version_string

#write(output = $stdout, indent = -1, transtive = false, ie_hack = false, encoding = nil) #write(options={:output) ⇒ $stdout, :indent

#xml_decl ⇒ xml_decl

`XMLTokens` - Included

`Namespace` - Included

`Element` - Inherited

`Element` - Inherited

`Parent` - Inherited

`Child` - Inherited

`Element` - Inherited

`Namespace` - Included

`Parent` - Inherited

`Child` - Inherited

`Node` - Included

`Element` - Inherited

`Namespace` - Included

`Parent` - Inherited

`Child` - Inherited

`Node` - Included

.new(string = nil, context = {}) ⇒ `Document` .new(io_stream = nil, context = {}) ⇒ `Document` .new(document = nil, context = {}) ⇒ `Document`

#stand_alone? ⇒ `Boolean` (readonly)

#add(xml_decl) ⇒ `self` #add(doc_type) ⇒ `self` #add(object) ⇒ `self`
Also known as: #<<

#add_element(name_or_element = nil, attributes = nil) ⇒ `new_element`

#clone ⇒ `Document`

#doctype ⇒ `doc_type`^?

#encoding ⇒ `encoding_string`

#expanded_name ⇒ `empty_string` Also known as: #name

#node_type ⇒ `Document`

#root ⇒ `root_element`^?

#version ⇒ `version_string`

#write(output = $stdout, indent = -1, transtive = false, ie_hack = false, encoding = nil) #write(options={:output) ⇒ $`stdout`, `:indent`