notify_slack.sh

#!/bin/bash
########################################
#
# This script notifies slack
# when this machine starts up
#
########################################

#This reads in the webhook URL from a file
#just replace it with you actual webhook URL
slack_url=`cat //usr/bin/slack_url`

start_text="Power is UP "
start_text+="Name  : `hostname`"
start_text+="\n Internal-IP  : `ip route get 8.8.8.8 | awk '{print $NF; exit}'`"
start_text+="\n External-IP  : `curl ifconfig.co` \n"
start_text+="\n  [+] for OK  : `service --status-all | grep openvpn`"
start_text+="\n  [+] for OK  : `service --status-all | grep ssh` \n "
start_text+="\n `grep MemTotal /proc/meminfo` \n"
start_text+="\n Espaço nas Drives"
start_text+="\n `df -h | grep /dev/mmc | sed ':a;N;$!ba;s/\n/\\\n/g'`"
start_text+="\n `df -h | grep /dev/sd | sed ':a;N;$!ba;s/\n/\\\n/g'`"

curl -H "Content-type:application/json" \
   -X POST -d \
   '{
      "channel":"#ll-osmc",
      "username" : "RaspBerryPi",
      "icon_emoji" : ":raspberrypi:",
      "attachments" : [
        {
          "fallback": "OSMC is up and running!",
          "color" : "good",
          "fields" : [
            {
               "title" : "OSMC Starting Up!",
               "value" : "'"$start_text"'",
               "short" : "true"
            }
          ]
        }
      ]
    }
   ' $slack_url

exit 0

For this to work it is necessary to create a file slack_url on /usr/bin/ with slack-Hook in it or

sudo bash -c 'cat << EOF > /usr/bin/slack_url
https://hooks.slack.com/services/Your-hook-here
EOF'
sudo chmod +x /usr/bin/slack_url