gecko-dev/dom/base/test/bug704320_counter.sjs

// Handle counting loads for bug 704320.

const SHARED_KEY="bug704320_counter";
const DEFAULT_STATE = {'css': {'count': 0, 'referrers': []},
                       'img': {'count': 0, 'referrers': []},
                       'js':  {'count': 0, 'referrers': []}};
const TYPE_MAP = {'css': 'text/css',
                  'js':  'application/javascript',
                  'img': 'image/png',
                  'html': 'text/html'};

// Writes an image to the response
function WriteOutImage(response)
{
  var file = Components.classes["@mozilla.org/file/directory_service;1"]
             .getService(Components.interfaces.nsIProperties)
             .get("CurWorkD", Components.interfaces.nsIFile);

  file.append("tests");
  file.append("image");
  file.append("test");
  file.append("mochitest");
  file.append('blue.png');

  var fileStream = Components.classes['@mozilla.org/network/file-input-stream;1']
                   .createInstance(Components.interfaces.nsIFileInputStream);
  fileStream.init(file, 1, 0, false);
  response.bodyOutputStream.writeFrom(fileStream, fileStream.available());
}

function handleRequest(request, response)
{
  var query = {};
  request.queryString.split('&').forEach(function (val) {
    var [name, value] = val.split('=');
    query[name] = unescape(value);
  });

  var referrerLevel = "none";
  if (request.hasHeader('Referer')) {
    let referrer = request.getHeader('Referer');
    if (referrer.indexOf("bug704320") > 0) {
      referrerLevel = "full";
    } else if (referrer == "http://mochi.test:8888/") {
      referrerLevel = "origin";
    }
  }

  var state = getSharedState(SHARED_KEY);
  if (state === '') {
    state = DEFAULT_STATE;
  } else {
    state = JSON.parse(state);
  }

  response.setStatusLine(request.httpVersion, 200, "OK");


  //avoid confusing cache behaviors
  response.setHeader("Cache-Control", "no-cache", false);

  if ("reset" in query) {
    //reset server state
    setSharedState(SHARED_KEY, JSON.stringify(DEFAULT_STATE));
    //serve any CSS that we want to use.
    response.write("");
    return;
  }

  if ("results" in query) {
    response.setHeader("Content-Type", "text/javascript", false);
    response.write(JSON.stringify(state));
    return;
  }

  if ('type' in query) {
    state[query.type].count++;
    response.setHeader("Content-Type", TYPE_MAP[query.type], false);
    if (state[query.type].referrers.indexOf(referrerLevel) < 0) {
      state[query.type].referrers.push(referrerLevel);
    }

    if (query.type == 'img') {
      WriteOutImage(response);
    }
  }

  if ('content' in query) {
    response.write(unescape(query['content']));
  }

  setSharedState(SHARED_KEY, JSON.stringify(state));
  return;
}