method

to_xml

rails latest stable - Class: ActiveRecord::Base

to_xml(options = {})

public

Builds an XML document to represent the model. Some configuration is availble through options, however more complicated cases should use Builder.

By default the generated XML document will include the processing instruction and all object’s attributes. For example:

  <?xml version="1.0" encoding="UTF-8"?>
  <topic>
    <title>The First Topic</title>
    <author-name>David</author-name>
    <id type="integer">1</id>
    <approved type="boolean">false</approved>
    <replies-count type="integer">0</replies-count>
    <bonus-time type="datetime">2000-01-01T08:28:00+12:00</bonus-time>
    <written-on type="datetime">2003-07-16T09:28:00+1200</written-on>
    <content>Have a nice day</content>
    <author-email-address>david@loudthinking.com</author-email-address>
    <parent-id></parent-id>
    <last-read type="date">2004-04-15</last-read>
  </topic>

This behaviour can be controlled with :only, :except, and :skip_instruct for instance:

  topic.to_xml(:skip_instruct => true, :except => [ :id, bonus_time, :written_on, replies_count ])

  <topic>
    <title>The First Topic</title>
    <author-name>David</author-name>
    <approved type="boolean">false</approved>
    <content>Have a nice day</content>
    <author-email-address>david@loudthinking.com</author-email-address>
    <parent-id></parent-id>
    <last-read type="date">2004-04-15</last-read>
  </topic>

To include first level associations use :include

  firm.to_xml :include => [ :account, :clients ]

  <?xml version="1.0" encoding="UTF-8"?>
  <firm>
    <id type="integer">1</id>
    <rating type="integer">1</rating>
    <name>37signals</name>
    <clients>
      <client>
        <rating type="integer">1</rating>
        <name>Summit</name>
      </client>
      <client>
        <rating type="integer">1</rating>
        <name>Microsoft</name>
      </client>
    </clients>
    <account>
      <id type="integer">1</id>
      <credit-limit type="integer">50</credit-limit>
    </account>
  </firm>

# File activerecord/lib/active_record/base.rb, line 1685
      def to_xml(options = {})
        options[:root]    ||= self.class.to_s.underscore
        options[:except]    = Array(options[:except]) << self.class.inheritance_column unless options[:only] # skip type column
        root_only_or_except = { :only => options[:only], :except => options[:except] }

        attributes_for_xml = attributes(root_only_or_except)
        
        if include_associations = options.delete(:include)
          include_has_options = include_associations.is_a?(Hash)
          
          for association in include_has_options ? include_associations.keys : Array(include_associations)
            association_options = include_has_options ? include_associations[association] : root_only_or_except

            case self.class.reflect_on_association(association).macro
              when :has_many, :has_and_belongs_to_many
                records = send(association).to_a
                unless records.empty?
                  attributes_for_xml[association] = records.collect do |record| 
                    record.attributes(association_options)
                  end
                end
              when :has_one, :belongs_to
                if record = send(association)
                  attributes_for_xml[association] = record.attributes(association_options)
                end
            end
          end
        end

        attributes_for_xml.to_xml(options)
      end

1Note

New and improved version

Soleone · Mar 24, 20091 thank

As this method is now deprecated, check the documentation for the new version (adds some more options), which gets included via a module:

ActiveRecord::Serialization#to_xml

to_xml

Method deprecated or moved

1Note

New and improved version

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