Automated Page Speed Insights monitoring Google App Script snippet

psi-automated-monitoring.js

var scriptProperties = PropertiesService.getScriptProperties();
var pageSpeedApiKey = '';
var pageSpeedMonitorUrls = [
  'https://www.example-url-here.de'
];

function createHeadingIfNoteExist() {
  var spreadsheet = SpreadsheetApp.getActiveSpreadsheet();
  var sheet = spreadsheet.getSheetByName('Sheet1');
  
  var firstCell = sheet.getRange('A1:A1').getValues()[0];
  if (firstCell == '') {
    sheet.appendRow([
      'Date',
      'Url',
      'Start Render (Desktop)',
      'Speed Index (Desktop)',
      'Interactive (Desktop)',
      'First Cpu Idle (Desktop)',
      'Estimated Input Latency (Desktop)',
      'Start Render (Mobile)',
      'Speed Index (Mobile)',
      'Interactive (Mobile)',
      'First Cpu Idle (Mobile)',
      'Estimated Input Latency (Mobile)'
    ]);
  }
}

function monitor() {
  createHeadingIfNoteExist();
  
  for (var i = 0; i < pageSpeedMonitorUrls.length; i++) {
    var url = pageSpeedMonitorUrls[i];
    var desktop = callPageSpeed(url, 'desktop');
    var mobile = callPageSpeed(url, 'mobile');
    addRow(url, desktop, mobile);
  }
}

function callPageSpeed(url, strategy) {
  var pageSpeedUrl = 'https://www.googleapis.com/pagespeedonline/v5/runPagespeed?' +
  'url=' + encodeURIComponent(url) +
  '&key=' + pageSpeedApiKey +
  '&category=performance' + 
  '&strategy=' + strategy;
  
  var response = UrlFetchApp.fetch(pageSpeedUrl);
  var json = response.getContentText();
  return JSON.parse(json);
}

function addRow(url, desktop, mobile) {  
  var spreadsheet = SpreadsheetApp.getActiveSpreadsheet();
  var sheet = spreadsheet.getSheetByName('Sheet1');
  sheet.appendRow([
    Utilities.formatDate(new Date(), 'GMT', 'yyyy-MM-dd'),
    url,
    getLighthouseMetric(desktop, 'first-contentful-paint'),
    getLighthouseMetric(desktop, 'speed-index'),
    getLighthouseMetric(desktop, 'interactive'),
    getLighthouseMetric(desktop, 'first-cpu-idle'),
    getLighthouseMetric(desktop, 'estimated-input-latency'),
    getLighthouseMetric(mobile, 'first-contentful-paint'),
    getLighthouseMetric(mobile, 'speed-index'),
    getLighthouseMetric(mobile, 'interactive'),
    getLighthouseMetric(mobile, 'first-cpu-idle'),
    getLighthouseMetric(mobile, 'estimated-input-latency'),
  ]);
}

function getLighthouseMetric(data, metric)
{
  var value = data.lighthouseResult.audits[metric].displayValue;
                  
  value = value.split('ms')[0];
  value = value.split('s')[0];
  
  return value.trim();
}