无法 map Nginx 端口 80 与 docker 容器端口 80

Question

I'm running a NodeJS app that is running on port 4242 and here's the dockefile, docker-compose and nginx conf looks like this

Dockerfile

FROM node:12-alpine
COPY package.json package-lock.json ./
RUN npm ci
COPY . .
EXPOSE 4242
CMD node index.js.

Docker Compose

services:
   web:
      build: .
   ports:
      - "80:4242"
   environment:
   DATABASE_URL: <DB_URL>
   depends_on:
      - db
command: >
    npm run start"

NGINX

server {
listen 80;
server_name server_name;

location / {
        try_files $uri $uri/ =404;
        auth_basic "Restricted Content";
        auth_basic_user_file /etc/nginx/.htpasswd;
        proxy_pass http://localhost:80;
}
}

I wanted to make this app accessible via port 80 through Nginx along with with basic auth on port 80 but I'm not able to map the port correctly.

EDIT: I always get port already in use error because Nginx by default is listening on port 80 whereas and in docker-compose I'm mapping 80 with the 4242 which Dockerfile is exposing

Thanks in advance

Answer 1

You can't have both nginx and docker container on port 80.

They must listen to different ports to avoid "port already in use error".

You could map the container port 4242 to host port 4242: replace - "80:4242" by - "4242:4242" in docker-compose file.

Restart your container with docker-compose restart web , you can check that your container is running with docker-compose ps (you'll see mapped ports at the same time)

Then, you have to change nginx conf accordingly:

server {
  listen         80;
  server_name    your_server_name;

  location / {
    auth_basic "Restricted Content";
    auth_basic_user_file /etc/nginx/.htpasswd;
    proxy_pass http://localhost:4242;
  }
}

Notes:

• I removed try_files as it was bypassing the proxy_pass instruction. Please provide context if you try to achieve something else with try_files .
• Replace your_server_name with your real server name.
• reload nginx

In the end you have:

1. nginx (directly on host) listening on port 80,
2. location block with basic auth,
3. forwarding traffic to host port 4242,
4. which is mapped to docker container port 4242 with proxy_pass ,
5. Finally hitting your NodeJS app.