Build a Simple Website Monitoring System with SMS Alerts

We can create a periodic task that checks our website every 5 minutes and sends a message to our phone number in case something is wrong.

• Go to a block or create a new one.
• Create a new periodic task.
• Set cron to */5 * * * *
• Paste the following script into the script field.

url="http://yourwebsite.com/health"
max_attempts=5
twilio_sid="your_twilio_account_sid"
twilio_from_number="your_twilio_phone_number"
phone_numbers=("number1" "number2" "number3" "number4" "number5")

send_twilio_alert() {
  for phone_number in "${phone_numbers[@]}"
  do
    curl -X POST "https://api.twilio.com/2010-04-01/Accounts/$twilio_sid/Messages.json" \
    --data-urlencode "Body=Alert: The website $url is not responding!" \
    --data-urlencode "From=$twilio_from_number" \
    --data-urlencode "To=$phone_number" \
    -u "$twilio_sid:$CRED_TWILIO"
  done
}

# Exponential notation is used to check if website is up or not
attempt=1
while [ $attempt -le $max_attempts ]
do
  response=$(curl -s -o /dev/null -w "%{http_code}" $url)

  if [ "$response" -eq 200 ]; then
    echo "Website is up!"
    exit 0
  else
    echo "Attempt $attempt failed with response code $response. Waiting before retry..."
    sleep $((2**attempt))
  fi

  attempt=$((attempt+1))
done

echo "Website is down! Sending alert..."
send_twilio_alert