jstoxmlparser

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

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 David'sjstoxml, which performed a behavior that won't fit into my project. So I took on David's jstoxml and modified it to suit on my purpose. If you looking for complete and more stable version, please go to David's page. I'll update this readme once I finish develop my own version. Now the only difference between jstoxmlparser and jstoxml is the behavior handle object that contains array of objects. See jstoxml issue 33 and 34 for reference.

Installation

• npm install jstoxmlparser

Version 1.0.0

• first version to change behavior in jstoxml and now can be used to convert existing json with array of objects.

Examples

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

// Node
const { toXML } = require('jstoxmlparser');
 
// Browser
import { toXML } from 'jstoxmlparser';

Example 1: Simple object

toXML({
  foo: 'bar',
  foo2: 'bar2'
});

Output:

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

Note: because JavaScript doesn't allow duplicate key names, only the last defined key will be outputted. If you need duplicate keys, please use an array instead (see Example 2 below).

Example 2: Simple array (needed for duplicate keys)

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

Output:

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

Example 2-1: object array

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

Output:

<a><foo>bar</foo></a><a><foo>bar2</foo></a>

Example 3: Simple functions

toXML({ currentTime: () => new Date() });

Output:

<currentTime>Mon Oct 02 2017 09:34:54 GMT-0700 (PDT)</currentTime>

Example 4: XML tag attributes

toXML({
  _name: 'foo',
  _content: 'bar',
  _attrs: {
    a: 'b',
    c: 'd'
  }
});

Output:

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

Example 5: Tags mixed with text content

To output text content, set a key to null:

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

Output:

text1<foo>bar</foo>text2

Example 6: Nested tags (with indenting)

const xmlOptions = {
  header: false,
  indent: '  '
};
 
toXML({
  a: {
    foo: 'bar',
    foo2: 'bar2'
  }
}, xmlOptions);

Output:

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

Example 7: Nested tags with attributes (with indenting)

const xmlOptions = {
  header: false,
  indent: '  '
};
 
toXML({
  ooo: {
    _name: 'foo',
    _attrs: {
      a: 'b'
    },
    _content: {
      _name: 'bar',
      _attrs: {
        c: 'd'
      }
    }
  }
}, xmlOptions);

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:

const bar = {
  _name: 'bar',
  _attrs: {
    c: 'd'
  }
};
 
const foo = {
  _name: 'foo',
  _attrs: {
    a: 'b'
  },
  _content: bar
};
 
const xmlOptions = {
  header: false,
  indent: '  '
};
 
return toXML({
  ooo: foo
},
xmlOptions);

Example 8: Complex functions

Function outputs will be processed (fed back into toXML), meaning that you can output objects that will in turn be converted to XML.

toXML({
  someNestedXML: () => {
    return {
      foo: 'bar'
    }
  }
});

Output:

<someNestedXML><foo>bar</foo></someNestedXML>

Example 9: RSS Feed

const xmlOptions = {
  header: true,
  indent: '  '
};
 
toXML({
  _name: 'rss',
  _attrs: {
    version: '2.0'
  },
  _content: {
    channel: [
      {
        title: 'RSS Example'
      },
      {
        description: 'Description'},
      {
        link: 'google.com'},
      {
        lastBuildDate: () => new Date()
      },
      {
        pubDate: () => new Date()
      },
      {
        language: 'en'},
      {
        item: {
          title: 'Item title',
          link: 'Item link',
          description: 'Item Description',
          pubDate: () => new Date()
        }
      },
      {
        item: {
          title: 'Item2 title',
          link: 'Item2 link',
          description: 'Item2 Description',
          pubDate: () => new Date()
        }
      }
    ]
  }
}, xmlOptions);

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>

Example 10: Podcast RSS Feed

(see the Apple docs for more information)

const xmlOptions = {
  header: true,
  indent: '  '
};
 
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 & 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'
          }
        ]
      }
    ]
  }
}, xmlOptions);

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>

Example 11: Custom filter for XML entities, or whatever

const xmlOptions = {
  filter: {
    '<': '&lt;', 
    '>': '&gt;',
    '"': '&quot;',
    '\'': '&apos;',
    '&': '&amp;'
  }
};
 
toXML({
    foo: '<a>',
    bar: '"b"',
    baz: '\'&whee\''
}, xmlOptions);

Output:

<foo>&lt;a&gt;</foo><bar>&quot;b&quot;</bar><baz>&apos;&amp;whee&apos;</baz>

Example 11b: Custom filter for XML attributes

const xmlOptions = {
  attributesFilter: {
    '<': '&lt;', 
    '>': '&gt;',
    '"': '&quot;',
    '\'': '&apos;',
    '&': '&amp;'
  }
};
 
toXML({
  _name: 'foo',
  _attrs: { a: '<"\'&"foo>' }
}, xmlOptions);

Output:

<foo a="&lt;&quot;&apos;&amp;&quot;foo&gt;"/>

Example 12: Avoiding self-closing tags

If for some reason you want to avoid self-closing tags, you can pass in a special config option _selfCloseTag:

const xmlOptions = {
  _selfCloseTag: false
};
 
toXML({
  foo: '',
  bar: undefined
}, xmlOptions);

Output:

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

Example 13: Custom XML header

const xmlOptions = {
  header: '<?xml version="1.0" encoding="UTF-16" standalone="yes"?>'
};
 
toXML({
  foo: 'bar'
}, xmlOptions);

Output:

<?xml version="1.0" encoding="UTF-16" standalone="yes"?><foo>bar</foo><foo2>bar2</foo2>

Example 14: Emoji attribute support (needed for AMP)

toXML({
  html: {
    _attrs: {
      '⚡': true
    }
  }
});

Output:

<html ⚡/>

Example 15: Duplicate attribute key support

toXML({
  html: {
    _attrs: [
      {
        lang: 'en'
      },
      {
        lang: 'klingon'
      }
    ]
  }
});

Output:

<html lang="en" lang="klingon"/>

License

MIT