How to run a nats ws server on localhost - ssl

Question

I have a nats server on localhost or local docker with WS configuration. Nats require tls for websocket. I created a cert and key. But, on connect it throws an error TLS handshake error from 127.0.0.1:61732: remote error: tls: unknown certificate authority. What should I do?

Answer 1

For test env, you need to create a conf file like this:
# ws.conf
websocket {
# Specify a host and port to listen for websocket connections
#
# listen: "host:port"
# It can also be configured with individual parameters,
# namely host and port.
#
# host: "hostname"
port: 443
# For test environments, you can disable the need for TLS
# by explicitly setting this option to `true`
#
no_tls: true
}
I called this as ws.conf here, but you could name it as you wish. Note I explicitly set the no_tls to true and didn't passed any certificate.
Docker way
After that you need to create a Dockerfile, since the entrypoint of nats image is the nats executable, we could do this:
FROM nats:alpine
COPY ws.conf ws.conf
CMD [ "-c", "ws.conf" ]
Note in CMD I'm passing some params, let me explain:
-c is a shortcurt for --config option for nats server
ws.conf is the config file we created
Now you could build and run this image. Or alternatively you could create a docker-compose to do it for you, something like that:
version: "3.8"
services:
nats-ws:
dockerfile: Dockerfile
ports:
- 443:443
- 4222:4222
Standalone way
After create the ws.conf start the nats with the params equal to docker way.
nats-server -c path/to/ws.conf
Thats it, if everthing is right you will see this message in nats logs / stdout:
[1] 2021/04/25 18:29:52.854288 [INF] Starting nats-server
[1] 2021/04/25 18:29:52.854402 [INF] Version: 2.2.2
[1] 2021/04/25 18:29:52.854407 [INF] Git: [a5f3aab]
[1] 2021/04/25 18:29:52.854411 [INF] Name: NCXFZRJ6L2PYQM6DND5YRKZA5OMQBQTFGH7ATZULU3US7KBWQDU4RKE3
[1] 2021/04/25 18:29:52.854416 [INF] ID: NCXFZRJ6L2PYQM6DND5YRKZA5OMQBQTFGH7ATZULU3US7KBWQDU4RKE3
[1] 2021/04/25 18:29:52.854421 [INF] Using configuration file: ws.conf
[1] 2021/04/25 18:29:52.858602 [INF] Listening for websocket clients on ws://0.0.0.0:443
[1] 2021/04/25 18:29:52.858643 [WRN] Websocket not configured with TLS. DO NOT USE IN PRODUCTION!
[1] 2021/04/25 18:29:52.859209 [INF] Listening for client connections on 0.0.0.0:4222
[1] 2021/04/25 18:29:52.859696 [INF] Server is ready
Refs
nats flags
websocker config file