wait-for-services.sh

#!/usr/bin/bash

set -e

cmd="$@"

if [ ! -z "$POSTGRESQL_DATABASE" ]; then
  >&2 echo "Checking if PostgreSQL is up"
  until python3 -c "import psycopg2;c=psycopg2.connect(host=\"$POSTGRESQL_HOST\",database=\"$POSTGRESQL_DATABASE\",user=\"$POSTGRESQL_USER\",port=\"$POSTGRESQL_PORT\",password=\"$POSTGRESQL_PASSWORD\");c.close()" &> /dev/null; do
    >&2 echo "PostgreSQL is unavailable - sleeping"
    sleep 1
  done
else
  >&2 echo "Skipping PostgreSQL check"
fi

if [ ! -z "$VMAAS_WEBSOCKET_HOST" ]; then
  >&2 echo "Checking if websocket server is up"
  until curl http://$VMAAS_WEBSOCKET_HOST/api/v1/monitoring/health &>/dev/null; do
    >&2 echo "Websocket server is unavailable - sleeping"
    sleep 1
  done
else
  >&2 echo "Skipping websocket server check"
fi

if [ ! -z "$KAFKA_HOST" ] && echo "from kafka import KafkaConsumer" | python3 &> /dev/null; then
  >&2 echo "Checking if Kafka server is up"
  until echo "from kafka import KafkaConsumer;c=KafkaConsumer(bootstrap_servers=[\"$KAFKA_HOST:$KAFKA_PORT\"]);c.close()" | python3 &> /dev/null; do
    >&2 echo "Kafka server is unavailable - sleeping"
    sleep 1
  done
else
  >&2 echo "Skipping Kafka server check"
fi

>&2 echo "Everything is up - executing command"
exec $cmd