gistfile1.js

var util = require("util"),  
    http = require("http"),
    url  = require("url"),
    fileSystem = require('fs'),
    path = require('path');

var responseMap = [
  {pattern:/\btest\?test\=true$/, response:"test-ok.xml"},
  {pattern:/\btest\?test=true&henk=liev$/, response:"test-ok.xml"},
  // 'begins with' test
  {pattern:/\btest\?test=true&klaas=stom/, response:"test-ok.xml"},
  // partial match / ignore datetime test
  {pattern:/\btest\?yearCard=false&dateTime=(.*)&test=true/, response:"test-ok.xml"},
  // real life match
  {pattern:/\bmobile-api-planner\?yearCard=false&dateTime=(.*)&previousAdvices=0&hslAllowed=false&toStation=bd&nextAdvices=1&fromStation=rtd&departure=true/,
    response:"test-ok.xml"},

  {pattern:/\bmobile-api-planner\?(?=.*hslAllowed=true)(?=.*fromStation=ASD)(?=.*toStation=RTD)/, response:"ams-rtd-fyra.xml"},

  {pattern:/\bmobile-api-planner\?(?=.*fromCity=Amsterdam)(?=.*fromStreet=Nieuwezijds Achterburgwal)(?=.*toStation=RTD)/, response:"ams-nwz-rtd-fyra.xml"}
];

function findResponseFor(path) {
  var result = null;
  responseMap.forEach(function(candidate) {
    if (path.match(candidate.pattern)) {
      result = candidate.response;
      return;
    } 
  })
  return result;
}

function writeFileToResponse(responseFile, response) {
  var filePath = path.join(__dirname, 'response', responseFile);
  var stat = fileSystem.statSync(filePath);

  response.writeHead(200, {"Content-Type": "application/xml", 'Content-Length': stat.size});

  var readStream = fileSystem.createReadStream(filePath);

  readStream.on('data', function(data) {
    response.write(data);
  });

  readStream.on('end', function() {
    response.end();
  });
}

function writeWebserviceToResponse(request, response) {
  var params = url.parse(request.url);
  var options = {
    host: 'webservices.dinges.nl',
    path: params.path,
    headers: {'Authorization' : request.headers.authorization}
  };

  var req = http.get(options, function(res) {
    res.setEncoding('utf8');
    response.writeHead(res.statusCode, res.headers);
    res.on('data', function (chunk) {
      response.write(chunk);
    });  
    res.on('end', function() {
      response.end();
    });
  });

  req.on('error', function(e) {
    console.log('problem with request: ' + e.message);
  });
}

http.createServer(function(request, response) {  
  var params = url.parse(request.url);
  console.log("request params: " + util.inspect(params));

  var responseFile = findResponseFor(params.path);
  if (responseFile != null) {
    console.log("Response found: " + responseFile);
    writeFileToResponse(responseFile, response);
  } else {
    console.log("Response not found, calling NS API");
    writeWebserviceToResponse(request, response);
  }
    
}).listen(1337);  

util.puts("Server running at http://localhost:1337/");