#!/usr/bin/env bash

#

# dns-endpoints.sh

#

# Output zone records to correctly map to zonal endpoints for Confluent Cloud.

#

# Example:

#

# % ./dns-endpoints.sh lkc-1n0nvv-6k0qeg.us-central1.gcp.glb.confluent.cloud:9092 <my gcp project> <service attachment URI 1> <service attachment URI 2> <service attachment URI 3>

#

# Hosted zone domain: 6k0qeg.us-central1.gcp.confluent.cloud

# * A 10.0.0.2 10.0.0.3 10.0.0.4

# *.us-central1-a A 10.0.0.2

# *.us-central1-b A 10.0.0.3

# *.us-central1-c A 10.0.0.4

#

# % ./dns-endpoints.sh lkc-1n0nvv-6k0qeg.us-central1.gcp.glb.confluent.cloud:9092 <my gcp project> <service attachment URI>

#

# Hosted zone domain: 6k0qeg.us-central1.gcp.confluent.cloud

# * A 10.0.0.4

function parse_zone_from_service_attachment_uri() {

echo "$1" | awk -F/ '{print $NF}' | awk -F-service-attachment- '{print $NF}'

}

function parse_region_from_service_attachment_uri() {

echo "$1" | awk -F/regions/ '{print $NF}' | awk -F/ '{print $1}'

}

function hosted_zone_domain_from_bootstrap() {

}

gcloud 1>/dev/null 2>/dev/null

[[ $? == 127 ]] && echo "warning: please install 'gcloud'"

if [[ $# -lt 3 ]]; then

echo "usage: $0 <bootstrap> <my gcp project> <service attachment URI(s)...>" 1>&2

echo ""

echo "example: $0 lkc-1n0nvv-6k0qeg.us-central1.gcp.glb.confluent.cloud:9092 <my gcp project> <service attachment URI 1> <service attachment URI 2> <service attachment URI 3>"

exit 1

fi

bootstrap=$1

project=$2

declare -A dnsrecord

declare allzonerecord

IFS='

'

for sa_uri in "${@:3}"; do

zoneName=$(parse_zone_from_service_attachment_uri "$sa_uri")

ip=$(gcloud --project "$project" compute forwarding-rules list --filter="target:$sa_uri" --format='value(IPAddress)')

dnsrecord[$zoneName]=$ip

allzonerecord+=("$ip")

done

printf "Hosted zone domain: %s\n\n" "$(hosted_zone_domain_from_bootstrap "$bootstrap")"

# shellcheck disable=SC2059

fmt=" %-25s A %s\n"

if [[ ${#dnsrecord[@]} -gt 1 ]]; then # multi-zone

printf "$fmt" "*" "$(sort <<<${allzonerecord[*]} | xargs)"

for id in "${!dnsrecord[@]}"; do

printf "$fmt" "*.$id" "${dnsrecord[$id]}"

done

else # single-zone

for id in "${!dnsrecord[@]}"; do

singlezonerecord=${dnsrecord[$id]}

done

printf "$fmt" "*" "$singlezonerecord"

fi