Sync two Heroku Postgres databases via pg:backups

heroku_pg_sync.sh

#!/bin/bash
set -e
######## Heroku Postgres Sync Script #######
## Author: Raj <[email protected]>
## License: MIT
##
## Syntax: sync.sh FROM_APP TO_APP [USE OLD BACKUP]
##
##  FROM_APP       Source application to obtain the backup.
##  TO_APP         Destination application to restore.
##  USE_OLD_BACKUP Presence of this argument disables capturing
##                 a new backup from the FROM_APP forcing the
##                 script to use last available backup.

FROM_DB=$1
TO_DB=$2
OLD_BACKUP=$3

if [ -z "$FROM_DB" -o -z "$TO_DB" ]
then
    echo "<script.sh> SOURCE_APP DESTINATION_APP [USE_OLD_BACKUP]"
    exit
fi


echo "NOTICE: Source      : $FROM_DB"
echo "NOTICE: Destination : $TO_DB"
read -p "Press [Enter] key to start or CTRL+C to bail..."

if [ -z "$OLD_BACKUP" ]
then
	echo "--- Capturing Backup ---"
	heroku pg:backups capture --app $FROM_DB
fi

echo -n "--- Retrieving Backup ID ---"
BACKUP_ID=$(heroku pg:backups --app $FROM_DB | sed -n '/=== Backups/,/=== Restores/p' | grep -E "Finished" | head -n1 | cut -d" " -f1)
echo " OK ${BACKUP_ID}"
echo -n "--- Retrieving Backup URL ---"
DB_URL=$(heroku pg:backups public-url $BACKUP_ID --app $FROM_DB | grep "http")
echo " OK"
echo "--- Reset destination ---"
heroku pg:reset DATABASE_URL --confirm $TO_DB
echo "--- Restoring to destination database ---"
heroku pg:backups restore "${DB_URL}" DATABASE_URL  --confirm $TO_DB --app $TO_DB