Docker nginx cannot reverse proxy within default network - docker

Question

I'm having problems with nginx reverse proxying as a docker container. My question is about how to correctly proxy pass nginx in a default docker network?
Here's my docker-compose.yml (unnecessary details omitted for brevity)
version: '3'
networks:
nginx_default:
external: true
services:
db:
image: postgres:10.2
ports:
- "5432:5432"
environment: ...
postgrest:
image: postgrest/postgrest
ports:
- "3000:3000"
environment: ...
nginx:
restart: always
image: nginx:latest
ports:
- "8080:80"
volumes:
- ./nginx/nginx.conf:/etc/nginx/sites-enabled/ruler
command: [nginx-debug, '-g', 'daemon off;']
webapp:
build:
context: "./"
dockerfile: Dockerfile.dev
volumes: ...
ports:
- "3001:3001"
environment: ...
Here's my nginx.conf
map $http_upgrade $connection_upgrade {
default upgrade;
'' close;
}
server {
listen 80;
server_name _;
gzip on;
gzip_proxied any;
gzip_types text/plain text/xml text/css application/x-javascript;
gzip_vary on;
gzip_disable "MSIE [1-6]\.(?!.*SV1)";
access_log /var/log/nginx/access.log;
error_log /var/log/nginx/error.log warn;
location / {
try_files $uri #node;
}
location /api/ {
try_files $uri #postgrest;
}
location #node {
proxy_pass http://webapp:3001;
proxy_redirect off;
proxy_http_version 1.1;
proxy_set_header Upgrade $http_upgrade;
proxy_set_header Connection 'upgrade';
proxy_cache_bypass $http_upgrade;
proxy_set_header X-Real-IP $remote_addr;
proxy_set_header Host $host;
proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
proxy_set_header X-Forwarded-Proto $scheme;
proxy_cache_bypass $http_cache_control;
add_header X-Proxy-Cache $upstream_cache_status;
}
location #postgrest {
proxy_pass http://postgrest:3000;
proxy_http_version 1.1;
default_type application/json;
proxy_set_header Connection "";
proxy_hide_header Content-Location;
add_header Content-Location /api/$upstream_http_content_location;
}
}
And my Dockerfile.dev
FROM node:8.9
WORKDIR /client
CMD npm run dev -- -p 3001
When I do $ docker-compose up -d everything starts without an error. After that I can successfully do $ curl http://127.0.0.1:3001/ (webapp) and $ curl http://127.0.0.1:3000 (postgrest).
But when I try $ curl http://127.0.0.1:8080/ (nginx should handle here the proxying) I get default nginx welcome page. Also $ curl http://127.0.0.1:8080/api/ is not hitting the API :/
What may be the cause? Using $ docker inspect I see that every container is in the same default network.
Edit: Using $ docker-compose logs seems like the default network is not used at all O_o
docker-compose logs
WARNING: Some networks were defined but are not used by any service: nginx_default
Attaching to ruler_webapp_1, ruler_nginx_1
webapp_1 |
webapp_1 | > ruler# dev /client
webapp_1 | > next "-p" "3001"
webapp_1 |
webapp_1 | > Using external babel configuration
webapp_1 | > Location: "/client/.babelrc"
webapp_1 | DONE Compiled successfully in 1741ms09:04:49
webapp_1 |

Answer 1

My guess is you mapped your local nginx configuration file to the wrong file on the container side. The default configuration file for the nginx image is located at /etc/nginx/conf.d/default.conf so the volume of the nginx container should be:
./nginx/nginx.conf:/etc/nginx/conf.d/default.conf:ro
You can check your configuration file is used correctly by executing:
docker-compose exec nginx nginx -T
Side notes:
Never use the latest tag, because in some time you may face broken compatibility issues. Use fixed version tag 1, 1.13 etc. instead
You don't need to publish ports everywhere, eg. 3000:3000, 3001:3001. Those ports will be accessible internally by containers

Answer 2

Your config is a partial config and not a complete nginx config. So it needs to go inside conf.d inside the container and not on nginx.conf or sites-enabled. So change
volumes:
- ./nginx/nginx.conf:/etc/nginx/sites-enabled/ruler
to
volumes:
- ./nginx/nginx.conf:/etc/nginx/conf.d/default.conf
And now it should start working