whistle/lib/util/log-server.js

HTTP, HTTPS, Websocket debugging proxy

var MAX_LENGTH = 512;
var MIN_LENGTH = 400;
var SIZE = 1024 * 32;
var COUNT = 100;
var count = 0;
var logs = [];

function getLogs(startTime, count) {
  var len = logs.length;
  if (!len || startTime == -1) {
    return [];
  }

  count = Math.min(count || COUNT, len);
  if (startTime == -2) {
    return logs.slice(0, count);
  }

  startTime = ((startTime || Date.now() - 3000) + '').split('-');

  startTime[0] = parseInt(startTime[0], 10) || 0;
  startTime[1] = parseInt(startTime[1], 10) || 0;

  if (compareId(logs[0].id, startTime)) {

    return logs.slice(0, count);
  }

  var end = len - 1;
  if (!end || !compareId(logs[end].id, startTime)) {
    return  [];
  }

  var index = getIndex(startTime, 0, end);
  return logs.slice(index, index + count);
}

function getIndex(startTime, start, end) {
  if (end - start <= 1) {
    return compareId(logs[start].id, startTime) ? start : end;
  }

  var mid = Math.floor((start + end) / 2);
  return compareId(logs[mid].id, startTime) ? getIndex(startTime, start, mid) : getIndex(startTime, mid + 1, end);
}

function compareId(curId, refId) {
  curId = curId.split('-');
  return curId[0] > refId[0] || (curId[0] == refId[0] && curId[1] > refId[1]);
}

module.exports = function init(proxy) {

  proxy.addLog = function set(log) {
    if (!log) {
      return;
    }

    var now = Date.now();
    var text = log.text;
    if (text == null) {
      text = '';
    } else if (typeof text != 'string') {
      text += '';
    }
    logs.push({
      id: now + '-' + ++count,
      date: now,
      level: /^fatal|error|warn|info|debug$/.test(log.level) ? log.level : 'info',
      text: text.substring(0, SIZE)
    });

    var len = logs.length;
    if (len > MAX_LENGTH) {
      logs = logs.slice(len - MIN_LENGTH, len);
    }
  };

  proxy.getLogs = getLogs;
};