How to use the swagger-ui.dist function in swagger-ui

"use strict";

var P = require('bluebird');
var fs = P.promisifyAll(require('fs'));
var path = require('path');
// Swagger-ui helpfully exports the absolute path of its dist directory
var docRoot = require('swagger-ui').dist + '/';
var HTTPError = require('./exports').HTTPError;

function staticServe(hyper, req) {
    var reqPath = req.query.path;

    var filePath = path.join(docRoot, reqPath);

    // Disallow relative paths.
    // Test relies on docRoot ending on a slash.
    if (filePath.substring(0, docRoot.length) !== docRoot) {
        throw new Error("Invalid path.");
    }

    return fs.readFileAsync(filePath)
    .then(function(body) {
        if (reqPath === '/index.html') {