I’m writing an application that connects to a Node.js WebSocket server (using ws) running on Cloud9. Previously this had been working without fault. However, today I suddenly started getting:
Error during WebSocket handshake: Unexpected response code: 502
when creating a new WebSocket, on the client (running outside Cloud9). I hadn’t changed anything with either the server or the client in between having a successful connection and getting these error responses.
Where might this problem be arising from? Could this be an issue with some change in Cloud9 recently? It seems odd that it arose without any changes on my part.