How do I send an alert email if Gravwell has not received any logs for a period of time?

Ingester state monitoring is best accomplished in the automation system. Here is a sample script to try.

Below is a script which monitors ingesters and will send an email whenever it detects that the ingester has changed state (come online or gone offline).

var fromAddr = `sender@example.com`
var toAddr = `receiver@example.com`


MinVer(3, 3, 6)
require(`utils/ingesterTracker.ank`, `df2c1a8792d12be066fec5ea7146ba5325bbaa1d`)
require(`email/htmlEmail.ank`, `df2c1a8792d12be066fec5ea7146ba5325bbaa1d`)

var pit = PersistentIngesterTracker

err = pit.Load()
if err != nil {
return err
}
err = pit.Scan()
if err != nil {
return err
}

var changed = pit.ChangedStates()
if len(changed) == 0 {
return pit.Save() //we are done
}

//something changed, send an alert email
var online = pit.FilterState(`ONLINE`)

var em = htmlEmail
em.SetTitle(`Ingester State Change Alert`)
em.AddSubTitle(`Ingester State Changes`)
em.AddTable(pit.Table(changed))
em.AddSubTitle(`Online Ingesters`)
em.AddTable(pit.Table(online))

err = em.SendEmail(fromAddr, toAddr, `Ingester State Change`)
if err != nil {
return err
}

//we got the email off, its safe to save our state back
return pit.Save()