Apache OpenWhisk Advanced Alarm Schedule Events

wake_up.js

var openwhisk = require('openwhisk');
var request = require('request-promise');

function getNextSunrise(lat, lng, when) {
  const options = {
    uri: 'https://api.sunrise-sunset.org/json',
    qs: { lat: lat, lng: lng, when: when },
    json: true
  }

  return request(options)
    .then(result => result.results.sunrise)
}

function calculateSchedule(sunrise) {
  console.log('Next sunrise:', sunrise)
  const sections = sunrise.split(':')
  const hour = sections[0], minute = sections[1]
  return `${minute} ${hour} * * *`
}

function scheduleSunriseEvent (sunrise) {
  const ow = openwhisk();
  const params = {cron: sunrise, maxTriggers: 1}
  return ow.feeds.delete({name: '/whisk.system/alarms/alarm', trigger: 'sunrise'}).then(() => {
    console.log('trigger feed deleted.')
    return ow.feeds.create({name: '/whisk.system/alarms/alarm', trigger: 'sunrise', params: params})
  }).then(result => {
    console.log('trigger feed created.')
  })
  .catch(err => {
    console.error('failed to create/delete trigger', err)
    console.log("ERROR", err.error.response.result)
  })
}

function main(params) {
  console.log('GOOD MORNING!')
    
  return getNextSunrise(params.lat, params.lng, 'tomorrow')
    .then(calculateSchedule)
    .then(scheduleSunriseEvent)
}