Accessing docker container websocket through nginx or traefik via html web page?

Question

I have two docker containers running - one has a websocket and the other is an nginx container. Setup using docker-compose.yml as follows:

version: "3.5"

  websocket: 
    build:
      context: .
      dockerfile: Dockerfile
    ports: 
      - "6000:7000"

  nginx:
    image: nginx:alpine
    restart: always
    ports:
      - "120:80"

In my index.html in the nginx container, I currently have to set socketUrl: "http://192.168.X.X:6000",i.e. the local IP address for the websocket container.

Is there a way of setting up nginx so that socketUrl: "http://websocket:7000"? Either using nginx or traefik?

If I run on different machines I have to manually edit the socketUrl for the new machine. I'd like the setup to be standard across machines so that I can access the websocket via html at http://192.168.X.X:120

Answer 1

Use links to access the other container via hostname:

version: "3.5"

services:
  websocket: 
    build:
      context: .
      dockerfile: Dockerfile
    container_name: websocket
    ports: 
      - "6000:7000"

  nginx:
    image: dperson/nginx
    container_name: nginx
    ports:
      - "120:80"
    environment:
      - STREAM=0.0.0.0:80;websocket:7000
    links:
      - websocket

if this doesn't work, force them to be on the same network:

version: "3.5"

services:
  websocket: 
    build:
      context: .
      dockerfile: Dockerfile
    container_name: websocket
    ports: 
      - "6000:7000"
    networks:
      - default

  nginx:
    image: dperson/nginx
    container_name: nginx
    ports:
      - "120:80"
    environment:
      - STREAM=0.0.0.0:80;websocket:7000
    links:
      - websocket
    networks:
      - default

networks:
  default: