karma-xml2js-preprocessor

Preprocessor for converting XML files into JavaScript DOM objects.

Installation

Just run:

npm install karma-xml2js-preprocessor --save-dev

Configuration

This is the default configuration:

// karma.conf.js
module.exports = function(config) {
  config.set({
    preprocessors: {
      '**/*.xml': ['xml2js']
    },
    files: [
      '**/*.xml',
      '*.js'
    ]
  });
};

How does it work ?

This preprocessor converts XML files into JS DOM objects and publishes them in the global window.__xml__.

Encoding / BOM support

Karma decodes file content as UTF-8 before handing it to preprocessors, which garbles files saved as UTF-16 (e.g. MusicXML exported by Finale or Sibelius) and produces an invalid generated .js. This preprocessor detects that case (UTF-16 content shows up riddled with NUL characters, which are illegal in XML), re-reads the raw bytes from disk, and decodes them according to the byte order mark (BOM): UTF-16 LE, UTF-16 BE, and UTF-8 with BOM are all handled, and any leading BOM is stripped so the document starts cleanly with <?xml. Plain UTF-8 files are unaffected.

For instance this doc.xml...

<?xml version="1.0" encoding="UTF-8"?>
<tag>content</tag>

... will be served as doc.xml.js:

window.__xml__ = window.__xml__ || {};
window.__xml__['doc.xml'] = /* DOM object obtained by parsing the content of doc.xml */;