How to create a bundle writer in LassoJs

bundle-writer-example.js

// ************************************
// ***** bundle-writer-example.js *****
//*************************************
var myWriter = require('./bundle-writer');

module.exports = function (myLasso, pluginConfig) {
    myLasso.config.writer = myWriter(pluginConfig, myLasso.config);
};

// ****************************
// ***** bundle-writer.js *****
//*****************************
function Bundle_getUrl(lassoContext) {
    var url = this.url;

    if (url) {
        return url;
    }

    var outputFile = this.outputFile;
    var urlPrefix = this.urlPrefix;
    var outputDir = this.outputDir;

    return urlPrefix + outputDir + outputFile;
}

module.exports = function cdnWriter(cdnWriterConfig, lassoConfig) {

    // Optional URL prefix to use when generating URLs to the bundled files
    var urlPrefix = cdnWriterConfig.urlPrefix;

    return {
        checkBundleUpToDate: function (bundle, lassoContext, callback) {
            // Bundle is not up-to-date and needs to be written
            callback(null, false);
        },
        checkResourceUpToDate: function (path, lassoContext, callback) {
            // Resource is not up-to-date and needs to be written
            callback(null, false);
        },
        /**
         * This will be called for JS and CSS bundles
         */
        writeBundle: function (reader, lassoContext, callback) {
            var input = reader.readBundle();
            var bundle = lassoContext.bundle;
            var contentType = bundle.contentType; // Either 'css' or 'js'

            bundle.setWritten(true);
            bundle.getUrl = Bundle_getUrl;
            bundle.urlPrefix = 'aaa';
            bundle.outputDir = '/frfr';
            bundle.outputFile = 'fooo.' + contentType;

            callback();
        },
        /**
         * This will be called for front-end assets such as images, fonts, etc.
         */
        writeResource: function (reader, lassoContext, callback) {
            var path = lassoContext.path;
            var readableResourceStream = reader.readResource();

            callback(null, {
                url: '/foobar.png'
            })
        }
    }

}

//**************
// *** Usage ***
//**************
plugins:[{
    plugin: require('./bundle-writer-example'),
    config: { a: 1 },
    enabled: true
}]

Open issues lasso-js/lasso#90