A Bash Script to Auto Renew Minio SSL

Hello everyone,

I wrote a script using bash to help renew lets encrypt ssl issued using on a minio instance. Minio is an s3 compatible storage. Basically, the ssl is issued via certbot but files need to be moved around. I found myself every now and then having my minio ssl expired and I didn't know. so i created this script to check daily when the hostname ssl expires and to renew it automatically. hope it helps someone with a similar need.

#!/bin/bash
PUSHOVER_API_TOKEN='xxxxx'
PUSHOVER_API_USER='xxxx'

HOSTNAME=$(hostname)


DEFAULT_PRIVATEKEY_LOCATION=/etc/letsencrypt/live/$HOSTNAME/privkey.pem
DEFAULT_CERTIFICATE_LOCATION=/etc/letsencrypt/live/$HOSTNAME/fullchain.pem

MINIO_USERNAME=minio-user
MINIO_PRIVATEKEY_LOCATION=/etc/minio/certs/private.key
MINIO_CERTIFICATE_LOCATION=/etc/minio/certs/public.crt


certexpiredays(){
    EXPIREDATE=$(openssl x509 -in $MINIO_CERTIFICATE_LOCATION -enddate -noout | sed "s/.*=\(.*\)/\1/")
    EXPIRE_DATE_IN_SECONDS=$(date -d "${EXPIREDATE}" +%s)
    NOW_IN_SECONDS=$(date -d now +%s)
    DATE_DIFF_IN_SECONDS=$(( (EXPIRE_DATE_IN_SECONDS - NOW_IN_SECONDS) / 86400 ))

    echo $DATE_DIFF_IN_SECONDS
}


notify(){
    STATUS=$1

    local TITLE="Renewal of Minio SSL"
    if [[  $STATUS -eq 0  ]]
    then
        local MESSAGE="SUCCESS! Minio SSL successfully replenished for https://$HOSTNAME:9000"
    else
        local MESSAGE="FAILED! Could not complete SSL renewal for minio. Status code: $STATUS for https://$HOSTNAME:9000"
    fi
    local SOUND=siren
    local TIME=$(date)
    local PRIORITY=0
    curl -s \
      --form-string "token=$PUSHOVER_API_TOKEN" \
      --form-string "user=$PUSHOVER_API_USER" \
      --form-string "title=$TITLE" \
      --form-string "message=$MESSAGE" \
      --form-string "timestamp=$TIME" \
      --form-string "sound=$SOUND" \
      --form-string "priority=$PRIORITY" \
      https://api.pushover.net/1/messages.json
}


#0.Check if renewal is needed in the first place

DAYS_TO_SSL_EXPIRY=$(certexpiredays)


if [[ (( $DAYS_TO_SSL_EXPIRY < 5 ))]]
then
    #1.Renew SSL
    echo "===Commencing SSL renewal...==="

    echo 2 | sudo certbot certonly --standalone -d $HOSTNAME

    if [ $? -eq 0 ]
    then
        echo "==>OK! SSL for minio has been requested successfully."
        echo "==>Copying SSL files...."

        #2. Copy SSL files to correct directory
        sudo cp -v $DEFAULT_PRIVATEKEY_LOCATION $MINIO_PRIVATEKEY_LOCATION
        sudo cp -v $DEFAULT_CERTIFICATE_LOCATION $MINIO_CERTIFICATE_LOCATION

        if [ $? -eq 0 ]
        then
            echo "==>OK! SSL files copied successfully..."

            #3. Change ownership of the SSLs
            sudo chown $MINIO_USERNAME:$MINIO_USERNAME $MINIO_PRIVATEKEY_LOCATION
            sudo chown $MINIO_USERNAME:$MINIO_USERNAME $MINIO_CERTIFICATE_LOCATION

            if [ $? -eq 0 ]
            then
                #4. Restart minio service
                sudo systemctl restart minio

                pgrep minio >/dev/null 2>&1
                STATE=$(echo $?)

                if [[  $STATE == 0  ]]
                then
                    echo "==>OK! Minio restarted successfully..."

                    echo "==>SUCCESS! SSL for minio replenished successfully."
                    notify 0
                else
                    echo "==>FAILED! Could not restart minio."
                    notify 1
                    exit
                fi
            fi
        else
            echo "==>FAILED! There was an error copying SSL files."
            notify 2
            exit
        fi

    else
        echo "==>FAILED! There was an error requesting for SSL for minio."
        notify 3
        exit
    fi
else
    echo "==>SSL for minio still valid for $DAYS_TO_SSL_EXPIRY days. Nothing to do. Bye"
    exit
fi