Will use Scaleway API to fetch public and private IP linked to an account, and paste them in a file. Can trigger when IP are updated, and relaunch a firewall

Get Scaleway Private and Public IP in a file.sh

#!/bin/bash
### description : fetch local network IP through Scaleway API (local IP changes on each reboot), and expose these IP in a file (e.g : for firewall purposed)
### Author : Charles Bourgeaux <charles@maecia.com>
### Date : 11 AUG 2020
### requires `jq` package

### Editable variables
SCALEWAY_TOKEN='xxxx-xxx-xxx-xxx-xxx'
SCALEWAY_ZONE='fr-par-1'
IP_LIST_FILE='/opt/sbin/local_authorized_ip'
LOGS='/var/log/ip_update'
### End of editable variables

DATE_LOGS=$(date '+%Y-%m-%d %H:%M:%S')

if [[ ! -f $IP_LIST_FILE ]]
then
    touch $IP_LIST_FILE
fi

CURRENT_SHA_SUM=$(sha1sum ${IP_LIST_FILE}|awk '{print $1}')
printf 'Current file checksum : %s\n' "$CURRENT_SHA_SUM"

#Purge file
cat /dev/null > ${IP_LIST_FILE}

printf '[%s] Requesting Scaleway API...\n' "$DATE_LOGS"
api_response=$(curl -s -H "X-Auth-Token: $SCALEWAY_TOKEN" "https://api.scaleway.com/instance/v1/zones/${SCALEWAY_ZONE}/servers")
if [ -n "$api_response" ]; then
        if jq -e . >/dev/null 2>&1 <<<"$api_response"; then
                echo 'JSON is valid'
        else
                printf '[%s] Failed to parse JSON !\n' "$DATE_LOGS" | tee -a $LOGS
                exit
        fi

        data=$(echo "$api_response" | jq .servers | jq -r '.[]' | jq .public_ip.address,.private_ip)
    while IFS= read -r line
    do
       echo "$line" | cut -d '"' -f 2 >> ${IP_LIST_FILE} 
    done < <(printf '%s\n' "$data")

    NEW_SHA_SUM=$(sha1sum ${IP_LIST_FILE}|awk '{print $1}')

    if [[ $NEW_SHA_SUM != "$CURRENT_SHA_SUM" ]]; 
    then
        printf '[%s] IP seems to have changed. New IP are :\n' "$DATE_LOGS" | tee -a $LOGS
        cat ${IP_LIST_FILE} | tee -a $LOGS
        # Action like : sudo /etc/init.d/firewall restart
    fi
else
    printf '[%s] Empty response from Scaleway API, aborting !\n' "$DATE_LOGS" | tee -a $LOGS
fi