docker-ttrss/root/etc/cont-init.d/98-wait-for-db

#!/usr/bin/with-contenv sh

# Wait for the DB to be reachable before proceeding. This avoids race condition
# whereby database is not ready (yet), and so TTRSS config isn't correctly created

#############
# This simply duplicates the logic from ttrss-configure-db.php
ename='DB';
eport=5432;

if [ '$DB_TYPE' = 'mysql' ];
then
	eport=3306;
	dbhost=$DB_PORT_3306_TCP_ADDR
else
	eport=5432;
	dbhost=$DB_PORT_5432_TCP_ADDR
fi
#############

# Run wait-for-it.sh to confirm DB comes up before we proceed
echo "Waiting up to 60s for $dbhost:$eport..."
/srv/wait-for $dbhost:$eport --timeout=60 -- echo "Done"