Log front-end events to New Relic and the browser as desired by environment.

watchLog.js

// Logging "constants"
nameSpace.watchLogDEBUG   = 7;
nameSpace.watchLogNOTICE  = 5;
nameSpace.watchLogWARNING = 4;
nameSpace.watchLogERROR   = 3;

/**
 * Log events.
 *
 * EXAMPLES:
 * nameSpace.watchLog('Should know when this happens');
 * nameSpace.watchLog('Should not happen', nameSpace.watchLogERROR);
 * nameSpace.watchLog('Not great if this happens', nameSpace.watchLogWARNING, 'someFeature', {
 *   path: nameSpace.util.parseUrl(window.location.href).path,
 *   linkText: $(this).text()
 * });
 *
 * @param {string} message
 *   Messages are intended more for simple NR Browser entries.
 * @param {int} severtity (optional)
 *   Severity of the event, values:
 *     nameSpace.watchLogDEBUG - developer helper,
 *     nameSpace.watchLogNOTICE - nice to know about,
 *     nameSpace.watchLogWARNING - need to know when occurs,
 *     nameSpace.watchLogERROR - should never happen
 * @param {string} type (optional)
 *   Type of item for easy lookup later.
 * @param {mixed} data (optional)
 *   Data to stash with the log event.
 */
nameSpace.watchLog = function watchLog(message, severity, type, data) {
  var settings = Site.settings.watchLog,
      err;

  // Defaults, and report threshold.
  type = type || 'watchLog';
  severity = severity || nameSpace.watchLogNOTICE;

  if (severity <= settings.threshold) {
    // Output to the browser.
    if (settings.debuging && window.console) {
      console.log(type + ': ' + severity + ' | ' + message);
      if (data) console.log(data);
    }
    // Send to NR Browser.
    if (window.NREUM) {
      err = new Error(type + ' (' + severity + ') ' + message);
      NREUM.noticeError(err);
    }
    // Send to NR Ingights.
    _.extend(data || {}, {severity: severity, message: message});
    nameSpace.insightsLogger(type, data);
  }
};


/**
 * Send events directly to NR Ingights.
 *
 * @param {object} data
 *   Data to insert into Insights. Properties will be query-able!
 * @param {string} type (optoinal)
 *   Action Name within Insights. Default: logger.
 */
nameSpace.insightsLogger = function insightsLogger(data, type) {
  if (window.newrelic) {
    type = type || 'logger';
    newrelic.addPageAction(type, data);
  }
};