lib/nokogiri/xml/document.rb
# coding: utf-8
# frozen_string_literal: true
require "pathname"
module Nokogiri
module XML
# Nokogiri::XML::Document is the main entry point for dealing with XML documents. The Document
# is created by parsing an XML document. See Nokogiri::XML::Document.parse for more information
# on parsing.
#
# For searching a Document, see Nokogiri::XML::Searchable#css and
# Nokogiri::XML::Searchable#xpath
class Document < Nokogiri::XML::Node
# See http://www.w3.org/TR/REC-xml-names/#ns-decl for more details. Note that we're not
# attempting to handle unicode characters partly because libxml2 doesn't handle unicode
# characters in NCNAMEs.
NCNAME_START_CHAR = "A-Za-z_"
NCNAME_CHAR = NCNAME_START_CHAR + "\\-\\.0-9"
NCNAME_RE = /^xmlns(?::([#{NCNAME_START_CHAR}][#{NCNAME_CHAR}]*))?$/
OBJECT_DUP_METHOD = Object.instance_method(:dup)
OBJECT_CLONE_METHOD = Object.instance_method(:clone)
private_constant :OBJECT_DUP_METHOD, :OBJECT_CLONE_METHOD
class << self
# Parse an XML file.
#
# +string_or_io+ may be a String, or any object that responds to
# _read_ and _close_ such as an IO, or StringIO.
#
# +url+ (optional) is the URI where this document is located.
#
# +encoding+ (optional) is the encoding that should be used when processing
# the document.
#
# +options+ (optional) is a configuration object that sets options during
# parsing, such as Nokogiri::XML::ParseOptions::RECOVER. See the
# Nokogiri::XML::ParseOptions for more information.
#
# +block+ (optional) is passed a configuration object on which
# parse options may be set.
#
# By default, Nokogiri treats documents as untrusted, and so
# does not attempt to load DTDs or access the network. See
# Nokogiri::XML::ParseOptions for a complete list of options;
# and that module's DEFAULT_XML constant for what's set (and not
# set) by default.
#
# Nokogiri.XML() is a convenience method which will call this method.
#
def parse(string_or_io, url = nil, encoding = nil, options = ParseOptions::DEFAULT_XML)
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 empty_doc?(string_or_io)
if options.strict?
raise Nokogiri::XML::SyntaxError, "Empty document"
else
return encoding ? new.tap { |i| i.encoding = encoding } : new
end
end
doc = 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
read_io(string_or_io, url, encoding, options.to_i)
else
# read_memory pukes on empty docs
read_memory(string_or_io, url, encoding, options.to_i)
end
# do xinclude processing
doc.do_xinclude(options) if options.xinclude?
doc
end
private
def empty_doc?(string_or_io)
string_or_io.nil? ||
(string_or_io.respond_to?(:empty?) && string_or_io.empty?) ||
(string_or_io.respond_to?(:eof?) && string_or_io.eof?)
end
end
##
# :singleton-method: wrap
# :call-seq: wrap(java_document) → Nokogiri::XML::Document
#
# ⚠ This method is only available when running JRuby.
#
# Create a Document using an existing Java DOM document object.
#
# The returned Document shares the same underlying data structure as the Java object, so
# changes in one are reflected in the other.
#
# [Parameters]
# - `java_document` (Java::OrgW3cDom::Document)
# (The class `Java::OrgW3cDom::Document` is also accessible as `org.w3c.dom.Document`.)
#
# [Returns] Nokogiri::XML::Document
#
# See also \#to_java
# :method: to_java
# :call-seq: to_java() → Java::OrgW3cDom::Document
#
# ⚠ This method is only available when running JRuby.
#
# Returns the underlying Java DOM document object for this document.
#
# The returned Java object shares the same underlying data structure as this document, so
# changes in one are reflected in the other.
#
# [Returns]
# Java::OrgW3cDom::Document
# (The class `Java::OrgW3cDom::Document` is also accessible as `org.w3c.dom.Document`.)
#
# See also Document.wrap
# The errors found while parsing a document.
#
# [Returns] Array<Nokogiri::XML::SyntaxError>
attr_accessor :errors
# When `true`, reparented elements without a namespace will inherit their new parent's
# namespace (if one exists). Defaults to `false`.
#
# [Returns] Boolean
#
# *Example:* Default behavior of namespace inheritance
#
# xml = <<~EOF
# <root xmlns:foo="http://nokogiri.org/default_ns/test/foo">
# <foo:parent>
# </foo:parent>
# </root>
# EOF
# doc = Nokogiri::XML(xml)
# parent = doc.at_xpath("//foo:parent", "foo" => "http://nokogiri.org/default_ns/test/foo")
# parent.add_child("<child></child>")
# doc.to_xml
# # => <?xml version="1.0"?>
# # <root xmlns:foo="http://nokogiri.org/default_ns/test/foo">
# # <foo:parent>
# # <child/>
# # </foo:parent>
# # </root>
#
# *Example:* Setting namespace inheritance to `true`
#
# xml = <<~EOF
# <root xmlns:foo="http://nokogiri.org/default_ns/test/foo">
# <foo:parent>
# </foo:parent>
# </root>
# EOF
# doc = Nokogiri::XML(xml)
# doc.namespace_inheritance = true
# parent = doc.at_xpath("//foo:parent", "foo" => "http://nokogiri.org/default_ns/test/foo")
# parent.add_child("<child></child>")
# doc.to_xml
# # => <?xml version="1.0"?>
# # <root xmlns:foo="http://nokogiri.org/default_ns/test/foo">
# # <foo:parent>
# # <foo:child/>
# # </foo:parent>
# # </root>
#
# Since v1.12.4
attr_accessor :namespace_inheritance
def initialize(*args) # :nodoc: # rubocop:disable Lint/MissingSuper
@errors = []
@decorators = nil
@namespace_inheritance = false
end
#
# :call-seq:
# dup → Nokogiri::XML::Document
# dup(level) → Nokogiri::XML::Document
#
# Duplicate this node.
#
# [Parameters]
# - +level+ (optional Integer). 0 is a shallow copy, 1 (the default) is a deep copy.
# [Returns] The new Nokogiri::XML::Document
#
def dup(level = 1)
copy = OBJECT_DUP_METHOD.bind_call(self)
copy.initialize_copy_with_args(self, level)
end
#
# :call-seq:
# clone → Nokogiri::XML::Document
# clone(level) → Nokogiri::XML::Document
#
# Clone this node.
#
# [Parameters]
# - +level+ (optional Integer). 0 is a shallow copy, 1 (the default) is a deep copy.
# [Returns] The new Nokogiri::XML::Document
#
def clone(level = 1)
copy = OBJECT_CLONE_METHOD.bind_call(self)
copy.initialize_copy_with_args(self, level)
end
# :call-seq:
# create_element(name, *contents_or_attrs, &block) → Nokogiri::XML::Element
#
# Create a new Element with `name` belonging to this document, optionally setting contents or
# attributes.
#
# This method is _not_ the most user-friendly option if your intention is to add a node to the
# document tree. Prefer one of the Nokogiri::XML::Node methods like Node#add_child,
# Node#add_next_sibling, Node#replace, etc. which will both create an element (or subtree) and
# place it in the document tree.
#
# Arguments may be passed to initialize the element:
#
# - a Hash argument will be used to set attributes
# - a non-Hash object that responds to \#to_s will be used to set the new node's contents
#
# A block may be passed to mutate the node.
#
# [Parameters]
# - `name` (String)
# - `contents_or_attrs` (\#to_s, Hash)
# [Yields] `node` (Nokogiri::XML::Element)
# [Returns] Nokogiri::XML::Element
#
# *Example:* An empty element without attributes
#
# doc.create_element("div")
# # => <div></div>
#
# *Example:* An element with contents
#
# doc.create_element("div", "contents")
# # => <div>contents</div>
#
# *Example:* An element with attributes
#
# doc.create_element("div", {"class" => "container"})
# # => <div class='container'></div>
#
# *Example:* An element with contents and attributes
#
# doc.create_element("div", "contents", {"class" => "container"})
# # => <div class='container'>contents</div>
#
# *Example:* Passing a block to mutate the element
#
# doc.create_element("div") { |node| node["class"] = "blue" if before_noon? }
#
def create_element(name, *contents_or_attrs, &block)
elm = Nokogiri::XML::Element.new(name, self, &block)
contents_or_attrs.each do |arg|
case arg
when Hash
arg.each do |k, v|
key = k.to_s
if key =~ NCNAME_RE
ns_name = Regexp.last_match(1)
elm.add_namespace_definition(ns_name, v)
else
elm[k.to_s] = v.to_s
end
end
else
elm.content = arg
end
end
if (ns = elm.namespace_definitions.find { |n| n.prefix.nil? || (n.prefix == "") })
elm.namespace = ns
end
elm
end
# Create a Text Node with +string+
def create_text_node(string, &block)
Nokogiri::XML::Text.new(string.to_s, self, &block)
end
# Create a CDATA Node containing +string+
def create_cdata(string, &block)
Nokogiri::XML::CDATA.new(self, string.to_s, &block)
end
# Create a Comment Node containing +string+
def create_comment(string, &block)
Nokogiri::XML::Comment.new(self, string.to_s, &block)
end
# The name of this document. Always returns "document"
def name
"document"
end
# A reference to +self+
def document
self
end
# :call-seq:
# collect_namespaces() → Hash<String(Namespace#prefix) ⇒ String(Namespace#href)>
#
# Recursively get all namespaces from this node and its subtree and return them as a
# hash.
#
# ⚠ This method will not handle duplicate namespace prefixes, since the return value is a hash.
#
# Note that this method does an xpath lookup for nodes with namespaces, and as a result the
# order (and which duplicate prefix "wins") may be dependent on the implementation of the
# underlying XML library.
#
# *Example:* Basic usage
#
# Given this document:
#
# <root xmlns="default" xmlns:foo="bar">
# <bar xmlns:hello="world" />
# </root>
#
# This method will return:
#
# {"xmlns:foo"=>"bar", "xmlns"=>"default", "xmlns:hello"=>"world"}
#
# *Example:* Duplicate prefixes
#
# Given this document:
#
# <root xmlns:foo="bar">
# <bar xmlns:foo="baz" />
# </root>
#
# The hash returned will be something like:
#
# {"xmlns:foo" => "baz"}
#
def collect_namespaces
xpath("//namespace::*").each_with_object({}) do |ns, hash|
hash[["xmlns", ns.prefix].compact.join(":")] = ns.href if ns.prefix != "xml"
end
end
# Get the list of decorators given +key+
def decorators(key)
@decorators ||= {}
@decorators[key] ||= []
end
##
# Validate this Document against it's DTD. Returns a list of errors on
# the document or +nil+ when there is no DTD.
def validate
return unless internal_subset
internal_subset.validate(self)
end
##
# Explore a document with shortcut methods. See Nokogiri::Slop for details.
#
# Note that any nodes that have been instantiated before #slop!
# is called will not be decorated with sloppy behavior. So, if you're in
# irb, the preferred idiom is:
#
# irb> doc = Nokogiri::Slop my_markup
#
# and not
#
# irb> doc = Nokogiri::HTML my_markup
# ... followed by irb's implicit inspect (and therefore instantiation of every node) ...
# irb> doc.slop!
# ... which does absolutely nothing.
#
def slop!
unless decorators(XML::Node).include?(Nokogiri::Decorators::Slop)
decorators(XML::Node) << Nokogiri::Decorators::Slop
decorate!
end
self
end
##
# Apply any decorators to +node+
def decorate(node)
return unless @decorators
@decorators.each do |klass, list|
next unless node.is_a?(klass)
list.each { |moodule| node.extend(moodule) }
end
end
alias_method :to_xml, :serialize
# Get the hash of namespaces on the root Nokogiri::XML::Node
def namespaces
root ? root.namespaces : {}
end
##
# Create a Nokogiri::XML::DocumentFragment from +tags+
# Returns an empty fragment if +tags+ is nil.
def fragment(tags = nil)
DocumentFragment.new(self, tags, root)
end
undef_method :swap, :parent, :namespace, :default_namespace=
undef_method :add_namespace_definition, :attributes
undef_method :namespace_definitions, :line, :add_namespace
def add_child(node_or_tags)
raise "A document may not have multiple root nodes." if (root && root.name != "nokogiri_text_wrapper") && !(node_or_tags.comment? || node_or_tags.processing_instruction?)
node_or_tags = coerce(node_or_tags)
if node_or_tags.is_a?(XML::NodeSet)
raise "A document may not have multiple root nodes." if node_or_tags.size > 1
super(node_or_tags.first)
else
super
end
end
alias_method :<<, :add_child
# :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::XML
end
#
# :call-seq: deconstruct_keys(array_of_names) → Hash
#
# Returns a hash describing the Document, to use in pattern matching.
#
# Valid keys and their values:
# - +root+ → (Node, nil) The root node of the Document, or +nil+ if the document is empty.
#
# In the future, other keys may allow accessing things like doctype and processing
# instructions. If you have a use case and would like this functionality, please let us know
# by opening an issue or a discussion on the github project.
#
# *Example*
#
# doc = Nokogiri::XML.parse(<<~XML)
# <?xml version="1.0"?>
# <root>
# <child>
# </root>
# XML
#
# doc.deconstruct_keys([:root])
# # => {:root=>
# # #(Element:0x35c {
# # name = "root",
# # children = [
# # #(Text "\n" + " "),
# # #(Element:0x370 { name = "child", children = [ #(Text "\n")] }),
# # #(Text "\n")]
# # })}
#
# *Example* of an empty document
#
# doc = Nokogiri::XML::Document.new
#
# doc.deconstruct_keys([:root])
# # => {:root=>nil}
#
# Since v1.14.0
#
def deconstruct_keys(keys)
{ root: root }
end
private
IMPLIED_XPATH_CONTEXTS = ["//"].freeze # :nodoc:
def inspect_attributes
[:name, :children]
end
end
end
end