Post random number from random.org to a channel on Slack

slack_random.sh

#!/bin/bash

RANDOM_URL=http://www.random.org/integers/?num=1\&min=1\&max=100\&col=1\&base=10\&format=plain\&rnd=new
RND_NUMBER=$(curl $RANDOM_URL)

MESSAGE=$RND_NUMBER
USERNAME="random.org"
CHANNEL="#random"
PAYLOAD="payload={\"channel\": \"$CHANNEL\", \"username\": \"$USERNAME\", \"text\": \"$MESSAGE\"}"

TOKEN=<ADD_TOKEN>
SLACK_URL=https://jive.slack.com/services/hooks/incoming-webhook?token=$TOKEN

curl -X POST --data "$PAYLOAD" $SLACK_URL