update linode ssl certs on nodebalancer with letsencrypt certs

update-linode-lb-ssl-cert.sh

#! /bin/bash

### ATTENTION : NOT READY FOR PRODUTION YET ###
### LINODE ACCEPTS BUT THEN BROWSERS SHOW   ###
### SSL_ERROR_RX_RECORD_TOO_LONG            ###

DOMAIN="example.com"
CERT_DIR="/opt/acme/certs/$DOMAIN"
TOKEN="XXXXXXXXXX"
NB_ID=XXXXX
NB_CONFIG_ID=XXXXX

# Check if cert exists
if ! [[ -f $CERT_DIR/fullchain.cer ]]; then
  echo "Cert file dont exist on $CERT_DIR"
  exit 1
fi

# Check if key exists
if ! [[ -f $CERT_DIR/$DOMAIN.key ]]; then
  echo "Cert key dont exist on $CERT_DIR"
  exit 2
fi

# Prepare cert info
SSL_CERT=$(sed -E ':a;N;$!ba;s/\r{0,1}\n/\\n/g' $CERT_DIR/fullchain.cer)
SSL_CERT_KEY=$(sed -E ':a;N;$!ba;s/\r{0,1}\n/\\n/g' $CERT_DIR/$DOMAIN.key)

# Generate json with certificate
if [[ -f $CERT_DIR/nodebalancer_ssl_cert.json ]]; then
  mv $CERT_DIR/nodebalancer_ssl_cert.json $CERT_DIR/nodebalancer_ssl_cert.json.bak.$(date -I)
fi

cat <<EOT >> $CERT_DIR/nodebalancer_ssl_cert.json
{
  "protocol":"https",
  "port": 443,
  "ssl_commonname": "$DOMAIN",
  "ssl_cert": "$SSL_CERT",
  "ssl_key": "$SSL_CERT_KEY"
}
EOT

# Update config on Linode NodeBalancer
curl -X PUT https://api.linode.com/v4/nodebalancers/$NB_ID/configs/$NB_CONFIG_ID \
-H "Authorization: Bearer $TOKEN" \
-H "Content-Type: application/json" \
-d @$CERT_DIR/nodebalancer_ssl_cert.json