Apollo Federation error when a service is down

apollo-federation-error.graphql

{
  "errors": [
    {
      "message": "request to http://localhost:4004/graphql failed, reason: connect ECONNREFUSED 127.0.0.1:4004",
      "extensions": {
        "code": "INTERNAL_SERVER_ERROR",
        "exception": {
          "stacktrace": [
            "FetchError: request to http://localhost:4004/graphql failed, reason: connect ECONNREFUSED 127.0.0.1:4004",
            "    at ClientRequest.<anonymous> (/Users/luca/Code/toptal/federation-demo/node_modules/node-fetch/lib/index.js:1455:11)",
            "    at ClientRequest.emit (events.js:210:5)",
            "    at Socket.socketErrorListener (_http_client.js:406:9)",
            "    at Socket.emit (events.js:210:5)",
            "    at emitErrorNT (internal/streams/destroy.js:92:8)",
            "    at emitErrorAndCloseNT (internal/streams/destroy.js:60:3)",
            "    at processTicksAndRejections (internal/process/task_queues.js:80:21)"
          ]
        }
      }
    }
  ],
  "data": {
    "topProducts": [
      {
        "name": "Table",
        "inStock": null
      },
      {
        "name": "Couch",
        "inStock": null
      },
      {
        "name": "Chair",
        "inStock": null
      }
    ]
  }
}