Google App Script to send a "post a pic" message twice a day

slice-of-life.gs

// Randomized posting of 2 messages
// One between between 8am and 3pm
// The other between 3pm and 10pm

function DelayedTrigger() {
  // for readability
  var minutes = 60 * 1000
  
  // There are 840 minutes between 8am and 10pm
  var morningDelay = randomInteger(1,420)
  var eveningDelay = randomInteger(421,840)


  const now = new Date()
  var morningAlertTime = new Date(now.getTime() + (morningDelay * minutes))
  var eveningAlertTime = new Date(now.getTime() + (eveningDelay * minutes))

  Logger.log("morningDelay=" + morningDelay)
  Logger.log("morning alert " + Utilities.formatDate(morningAlertTime,"CST", "yyyy-MM-dd HH:mm:ss"))

  Logger.log("eveningDelay=" + eveningDelay)
  Logger.log("evening alert " + Utilities.formatDate(eveningAlertTime,"CST", "yyyy-MM-dd HH:mm:ss"))

  // create morning and evening triggers
  ScriptApp.newTrigger("RandomAlert")
    .timeBased()
    .after(morningDelay * minutes)
    .create();

  ScriptApp.newTrigger("RandomAlert")
    .timeBased()
    .after(eveningDelay * minutes)
    .create();
}

function RandomAlert() {
  var randomMessage = {
    'username': 'slicebot',
    'text': '@channel Time to post a picture! Just whatever is around you. Mundane snapshots of life welcome.'
  }

  // get URL from Script Properties key-value store
  var mm_url = PropertiesService.getScriptProperties().getProperty('communitas_url') 

  // set the HTTP options, including the JSON payload
  var options = {
    'method' : 'post',
    'payload' : randomMessage,
    'contentType': 'application/json',
    'payload' : JSON.stringify(randomMessage)
  }

  // send the payload
  UrlFetchApp.fetch(mm_url, options);
}

// function to generate a random integer between 'min' and 'max'
function randomInteger(min, max) {
  return Math.floor(Math.random() * (max - min + 1)) + min;
}