api-piloted

api-piloted

$cat containerpilot.json
{
  "consul": "localhost:8500",
  "preStart": "/app/manage.sh prestart",
  "services": [
    {
      "name": "api",
      "health": "/usr/bin/curl -o /dev/null --fail -s http://localhost/health",
      "poll": 3,
      "ttl": 10,
      "port": 80
    }
  ],
  "coprocesses": [
    {
      "command": ["/usr/local/bin/consul", "agent",
                  "-data-dir=/data",
                  "-config-dir=/config",
                  "-rejoin",
                  "-retry-join", "{{ if .CONSUL_HOST }}{{ .CONSUL_HOST }}{{ else }}consul{{ end }}",
                  "-retry-max", "10",
                  "-retry-interval", "10s"],
      "restarts": "unlimited"
    }
  ],
  "backends": [
    {
      "name": "mongodb-replicaset",
      "poll": 3,
      "onChange": "/app/manage.sh db-change"
    }
  ]
}

$ cat manage.sh
#!/bin/sh

event=$1
echo "Received event:$event"

if [ "$event" = "prestart" ];then
  while [[ "$(curl -s http://${CONSUL_HOST}:8500/v1/health/service/mongodb-replicaset | grep passing)" = "" ]]
  do
    echo "db is not yet healthly..."
    sleep 5
  done
  echo "db is healthly, moving on..."
  exit 0
fi

# If db not accessible anymore, restart the api service
if [ "$event" = "db-change" ];then
  pkill -SIGHUP node
fi