Connection problems after upgrading Meteor from 2.2.1 to 2.5.6

[derwaldgeist]

trafficstars

We upgraded Meteor from 2.2.1 top 2.5.6, which was necessary due to an incompatibility with opensea.js. Everything works fine on the development server, but once I push the app to AWS (using mup), I am experiencing connection problems.

It should be noted that we're not using the Meteor webapp here, but a custom DDP protocol library for Unity. The problems only occur in this scenario (and with Meteor 2.5.6), not if I use the web app or Meteor 2.2.1.

The symptom: The app manages to connect to the server and also logs in successfully. But then, all of a sudden, the WebSocket shuts down for no reason. It looks as if some time-out knocks in. My app then tries to re-connect, which results in an endless loop of connections and disconnections.

I am wondering if the problem is related to Meteor itself or to the new Docker image I had to switch to when doing the upgrade (before: abernix/meteord:node-12-base, now: zodern/meteor:root).

My mup version is 1.5.7.