#!/bin/bash set -o errexit set -o pipefail set -o nounset # N.B. If only .env files supported variable expansion... export CELERY_BROKER_URL="${REDIS_URL}" python << END import sys import time import psycopg2 suggest_unrecoverable_after = 30 start = time.time() while True: try: psycopg2.connect( dbname="${POSTGRES_DB}", user="${POSTGRES_USER}", password="${POSTGRES_PASSWORD}", host="${POSTGRES_HOST}", port="${POSTGRES_PORT}", ) break except psycopg2.OperationalError as error: sys.stderr.write("Waiting for PostgreSQL to become available...\n") if time.time() - start > suggest_unrecoverable_after: sys.stderr.write(" This is taking longer than expected. The following exception may be indicative of an unrecoverable error: '{}'\n".format(error)) time.sleep(1) END >&2 echo 'PostgreSQL is available' exec "$@"