Logging

browserStats.js

function logBrowserStats() {
  function getAsObject(objectLike) {
    var obj = {}, key;
    for (key in objectLike) {
      var val = objectLike[key];
      if (typeof val === 'number' || typeof val === 'string') {
        obj[key] = val;
      }
    }
    return obj;
  }
  var browserStats = {
    screen: getAsObject(screen),
    window: {width: $(window).width(), height: $(window).height()},
    navigator: getAsObject(navigator)
  };
  logEvent('browser stats', browserStats);
}

client.js

var events = [];
var maxSeq = 0;
var curUploadingSeq, curUploadingEvents = null;

function uploadEvents() {
  if (curUploadingEvents === null && events.length !== 0) {
    curUploadingSeq = maxSeq++;
    curUploadingEvents = events.join('\n')+'\n';
    events = [];
    tryUpload();
  }
}

setInterval(uploadEvents, 30*1000); // upload every 30 seconds

function tryUpload() {
  $.ajax({
    type: 'POST',
    url: '/log_events/'+curUploadingSeq,
    data: {events: curUploadingEvents},
    timeout: 30000,
    success: function() {
      console.log('Successfully uploaded', curUploadingSeq);
      $('#connectionTrouble').hide();
      curUploadingEvents = null;
      uploadEvents();
    },
    error: function(xhr, textStatus, errorThrown) {
      // Try again in 5 seconds.
      console.log('Upload failed', textStatus, xhr);
      logEvent('trouble uploading');
      $('#connectionTrouble').show();
      setTimeout(tryUpload, 5000);
    }
  });
}


function logEvent(name) {
  var args = Array.prototype.slice.call(arguments);
  var event = {
    time: new Date().getTime(),
    lastMouseX: lastMouseX,
    lastMouseY: lastMouseY,
    name: name,
    args: args.slice(1)
  };
  console.log(name, event);
  events.push(JSON.stringify(event))
}

server.py

from flask import Flask, request, send_file, render_template, session

@app.route('/')
def index():
    if 'participant' in request.args:
        participant = request.args['participant']
    elif 'participant' in session:
        participant = session['participant']
    else:
        participant = ''.join(random.choice(string.ascii_letters) for i in xrange(4))
    numTrials = int(request.args.get('numTrials', 120))
    session['participant'] = participant
    startTime, condition = getCondition(participant)
    session['startTime'] = startTime.isoformat()
    return render_template('index.html', condition=condition, numTrials=numTrials)

def get_remote_addr():
    if 'X-Forwarded-For' in request.headers:
        return request.headers['X-Forwarded-For']
    else:
        return request.remote_addr

@app.route('/log_events/<int:seq>', methods=['POST'])
def log_events(seq):
    participant = session['participant']
    startTime = session['startTime']
    events = request.form['events']
    sessionLogPath = getSessionLogPath(participant, startTime)
    if not os.path.isdir(sessionLogPath):
        os.makedirs(sessionLogPath)
        with open(os.path.join(sessionLogPath, 'ip'), 'w') as f:
            print >>f, get_remote_addr()

    with open(os.path.join(sessionLogPath, '{0:03d}.txt'.format(seq)), 'wb') as f:
        f.write(events)
    return 'success'