Will keep trying indefinitely till a postgres database is available, helpful when scripts depend on docker-compose up

wait-for-db.sh

+#!/bin/bash
+
+if [ "$#" -lt 2 ]; then
+  echo "Usage: wait-for-db.sh [host] [port] [database]"
+  exit 1
+fi
+
+host="$1"
+port="$2"
+database="$3"
+waited=0
+delay=2
+
+source .env
+
+export PGPASSWORD=$DB_PASSWORD
+export PGUSER=$DB_USERNAME
+
+function try () {
+  return `psql -h $host -lq 2>/dev/null | cut -d \| -f 1 | grep -qw $database`
+}
+
+until try
+do
+  echo "Waiting for database to initialize... ${waited}s"
+  sleep "$delay"
+  waited=$(($waited + $delay))
+done