I’m having a problem that’s really frying my neurons - WebSocket related

[MichelDiz]

Hello everyone.

I followed the documentation carefully, but I just can’t connect my Vue.js application to the NATS server. I keep getting this error:

10.0.4.1:54336 - websocket handshake error: origin not allowed: not in the allowed list

Believe me I tried a lot of things.

However, this is not a trivial error. Look: the first IP belongs to Docker’s internal network. It’s not even the default configured IP for NATS. But there’s a catch: inside Docker, each new call uses a different port, just like router NAT. That makes debugging even harder, because I haven’t found any way to use wildcards (like **) to allow any port. That would have made things much easier.

So I tried putting NATS behind NGINX. Same problem. Even though NGINX is on the same network inside Docker, it still keeps changing ports constantly. That’s what’s keeping me up at night.

Has anyone faced this before or knows how to solve it? Thanks in advance!

[MichelDiz]

I was able to solve it migrating from NGINX to Traefik.