jstoxml

Convert JSON to XML (for RSS, Podcasts, etc.)

jstoxml

Everyone loves JSON, and more and more folks want to move that direction, but we still need things outputted in XML! Particularly for RSS feeds and Podcasts.

This is inspired by node-jsontoxml, which was found to be a bit too rough around the edges. jstoxml attempts to fix that by being more flexible.

  • supports a variety of inputs: objects, arrays, strings,
  • tabbed output (optional)
  • custom filters (& -> &, etc) (optional)
  • npm install jstoxml
  • IMPORTANT: empty text strings will now output as empty XML tags (NOT text content), which makes more sense and is more intuitive (see issue #3). To output text content, set the value to null instead (see Example 5 below).

For instance:

jstoxml.toXML({
  a: '1',
  foo: '',
  b: '2'
});
// Output: <a>1</a><foo></foo><b>2</b>
jstoxml.toXML({
  a: '1',
  foo: null,
  b: '2'
});
// Output: <a>1</a>foo<b>2</b>
  • Added support for custom filters (for XML, UTF-8 entities, or whatever you need it for)
  • Changed to a single options object, passed as the second parameter. This will break older versions that use the XML header or indentation! They will need to be updated (see the examples below).

First you'll want to require jstoxml in your script, and assign the result to the namespace variable you want to use (in this case jstoxml):

var jstoxml = require('jstoxml');

jstoxml has a very simple interface: jstoxml.toXML(input, addHeader [Boolean], indent [String]);

  • input: accepts objects, arrays, strings, and even functions
  • addHeader (optional): pass in true to include the XML header (<?xml version="1.0" encoding="UTF-8"?>)
  • indent (optional): string which is used as an indent (i.e. ' ')
jstoxml.toXML({
  foo: 'bar',
  foo2: 'bar2'
});

Output:

<foo>bar</foo><foo2>bar2</foo2>
jstoxml.toXML([
  {foo: 'bar'},
  {foo2: 'bar2'}
]);

Output:

<foo>bar</foo><foo2>bar2</foo2>

Because we can't have duplicate keys in objects, we have to take advantage of arrays to get duplicate tag names:

jstoxml.toXML([
  {foo: 'bar'},
  {foo: 'bar2'}
]);

Output:

<foo>bar</foo><foo>bar2</foo>
jstoxml.toXML({
  _name: 'foo',
  _content: 'bar',
  _attrs: {
    a: 'b',
    c: 'd'
  }
});

Output:

<foo a="b" c="d">bar</foo>

To output text content, set a key to null:

jstoxml.toXML({
  'text1': null,
  foo: 'bar',
  'text2': null
});
 

Output:

text1<foo>bar</foo>text2
jstoxml.toXML({
  a: {
    foo: 'bar',
    foo2: 'bar2'
  }
}, {header: false, indent: '  '});

Output:

<a>
  <foo>bar</foo>
  <foo2>bar2</foo2>
</a>
jstoxml.toXML({
  ooo: {
    _name: 'foo',
    _attrs: {
      a: 'b'
    },
    _content: {
      _name: 'bar',
      _attrs: {
        c: 'd'
      }
    }
  }
}, {header: false, indent: '  '});

Output:

<ooo>
  <foo a="b">
    <bar c="d"/>
  </foo>
</ooo>

Note that cases like this might be especially hard to read because of the deep nesting, so it's recommend you use something like this pattern instead, which breaks it up into more readable pieces:

var bar = {
  _name: 'bar',
  _attrs: {
    c: 'd'
  }
};
 
var foo = {
  _name: 'foo',
  _attrs: {
    a: 'b'
  },
  _content: bar
}
 
return jstoxml.toXML({
  ooo: foo
}, {header: false, indent: '  '})
jstoxml.toXML({
  onePlusTwofunction(){
    return 1 + 2;
  },
  datefunction(){
    return new Date();
  }
});

Output:

<onePlusTwo>3</onePlusTwo><date>Sat Jul 30 2011 17:49:52 GMT+0900 (JST)</date>
jstoxml.toXML({
  _name: 'rss',
  _attrs: {
    version: '2.0'
  },
  _content: {
    channel: [
      {title: 'RSS Example'},
      {description: 'Description'},
      {link: 'google.com'},
      {lastBuildDatefunction(){
        return new Date();
      }},
      {pubDatefunction(){
        return new Date();
      }},
      {language: 'en'},
      {item: {
        title: 'Item title',
        link: 'Item link',
        description: 'Item Description',
        pubDatefunction(){
          return new Date();
        }
      }},
      {item: {
        title: 'Item2 title',
        link: 'Item2 link',
        description: 'Item2 Description',
        pubDatefunction(){
          return new Date();
        }
      }}
    ]
  }
}, {header: true, indent: '  '});

Output:

<?xml version="1.0" encoding="UTF-8"?>
<rss version="2.0">
  <channel>
    <title>RSS Example</title>
    <description>Description</description>
    <link>google.com</link>
    <lastBuildDate>Sat Jul 30 2011 18:14:25 GMT+0900 (JST)</lastBuildDate>
    <pubDate>Sat Jul 30 2011 18:14:25 GMT+0900 (JST)</pubDate>
    <language>en</language>
    <item>
      <title>Item title</title>
      <link>Item link</link>
      <description>Item Description</description>
      <pubDate>Sat Jul 30 2011 18:33:47 GMT+0900 (JST)</pubDate>
    </item>
    <item>
      <title>Item2 title</title>
      <link>Item2 link</link>
      <description>Item2 Description</description>
      <pubDate>Sat Jul 30 2011 18:33:47 GMT+0900 (JST)</pubDate>
    </item>
  </channel>
</rss>

(see the Apple docs for more information)

jstoxml.toXML({
  _name: 'rss',
  _attrs: {
    'xmlns:itunes': 'http://www.itunes.com/dtds/podcast-1.0.dtd',
    version: '2.0'
  },
  _content: {
    channel: [
      {title: 'Title'},
      {link: 'google.com'},
      {language: 'en-us'},
      {copyright: 'Copyright 2011'},
      {'itunes:subtitle': 'Subtitle'},
      {'itunes:author': 'Author'},
      {'itunes:summary': 'Summary'},
      {description: 'Description'},
      {'itunes:owner': {
        'itunes:name': 'Name',
        'itunes:email': 'Email'
      }},
      {
        _name: 'itunes:image',
        _attrs: {
          href: 'image.jpg'
        }
      },
      {
        _name: 'itunes:category',
        _attrs: {
          text: 'Technology'
        },
        _content: {
          _name: 'itunes:category',
          _attrs: {
            text: 'Gadgets'
          } 
        }
      },
      {
        _name: 'itunes:category',
        _attrs: {
          text: 'TV &amp; Film'
        }
      },
      {
        item: [
          {title: 'Podcast Title'},
          {'itunes:author': 'Author'},
          {'itunes:subtitle': 'Subtitle'},
          {'itunes:summary': 'Summary'},
          {'itunes:image': 'image.jpg'},
          {
            _name: 'enclosure',
            _attrs: {
              url: 'http://example.com/podcast.m4a',
              length: '8727310',
              type: 'audio/x-m4a'
            }
          },
          {guid: 'http://example.com/archive/aae20050615.m4a'},
          {pubDate: 'Wed, 15 Jun 2011 19:00:00 GMT'},
          {'itunes:duration': '7:04'},
          {'itunes:keywords': 'salt, pepper, shaker, exciting'}
        ]
      },
      {
        item: [
          {title: 'Podcast2 Title'},
          {'itunes:author': 'Author2'},
          {'itunes:subtitle': 'Subtitle2'},
          {'itunes:summary': 'Summary2'},
          {'itunes:image': 'image2.jpg'},
          {
            _name: 'enclosure',
            _attrs: {
              url: 'http://example.com/podcast2.m4a',
              length: '655555',
              type: 'audio/x-m4a'
            }
          },
          {guid: 'http://example.com/archive/aae2.m4a'},
          {pubDate: 'Wed, 15 Jul 2011 19:00:00 GMT'},
          {'itunes:duration': '11:20'},
          {'itunes:keywords': 'foo, bar'}
        ]
      }
    ]
  }
}, {header: true, indent: '  '});

Output:

<?xml version="1.0" encoding="UTF-8"?>
<rss xmlns:itunes="http://www.itunes.com/dtds/podcast-1.0.dtd" version="2.0">
  <channel>
    <title>Title</title>
    <link>google.com</link>
    <language>en-us</language>
    <copyright>Copyright 2011</copyright>
    <itunes:subtitle>Subtitle</itunes:subtitle>
    <itunes:author>Author</itunes:author>
    <itunes:summary>Summary</itunes:summary>
    <description>Description</description>
    <itunes:owner>
      <itunes:name>Name</itunes:name>
      <itunes:email>Email</itunes:email>
    </itunes:owner>
    <itunes:image href="image.jpg"/>
    <itunes:category text="Technology">
      <itunes:category text="Gadgets"/>
    </itunes:category>
    <itunes:category text="TV &amp; Film"/>
    <item>
      <title>Podcast Title</title>
      <itunes:author>Author</itunes:author>
      <itunes:subtitle>Subtitle</itunes:subtitle>
      <itunes:summary>Summary</itunes:summary>
      <itunes:image>image.jpg</itunes:image>
      <enclosure url="http://example.com/podcast.m4a" length="8727310" type="audio/x-m4a"/>
      <guid>http://example.com/archive/aae20050615.m4a</guid>
      <pubDate>Wed, 15 Jun 2011 19:00:00 GMT</pubDate>
      <itunes:duration>7:04</itunes:duration>
      <itunes:keywords>salt, pepper, shaker, exciting</itunes:keywords>
    </item>
    <item>
      <title>Podcast2 Title</title>
      <itunes:author>Author2</itunes:author>
      <itunes:subtitle>Subtitle2</itunes:subtitle>
      <itunes:summary>Summary2</itunes:summary>
      <itunes:image>image2.jpg</itunes:image>
      <enclosure url="http://example.com/podcast2.m4a" length="655555" type="audio/x-m4a"/>
      <guid>http://example.com/archive/aae2.m4a</guid>
      <pubDate>Wed, 15 Jul 2011 19:00:00 GMT</pubDate>
      <itunes:duration>11:20</itunes:duration>
      <itunes:keywords>foo, bar</itunes:keywords>
    </item>
  </channel>
</rss>
jstoxml.toXML({
    foo: '<a>',
    bar: '"b"',
    baz: '\'&whee\''
},
{
    filter: {
        '<': '&lt;', 
        '>': '&gt;',
        '"': '&quot;',
        '\'': '&apos;',
        '&': '&amp;'
    }
});

Output:

<foo>&lt;a&gt;</foo><bar>&quot;b&quot;</bar><baz>&apos;&amp;whee&apos;</baz>
jstoxml.toXML({
  foo: '',
  bar: 'whee'
});

Output:

<foo></foo><bar>whee</bar>