Compose: nginx to expressjs

Docker: Version 18.02.0-ce-rc2-mac51 (22446)
Docker Compose: 1.19.0-rc2
OS: macOS Sierra 10.12.6

I’m using Nginx as a sidecar container to proxy an ExpressJS application, both Nginx and Express works but I cannot proxy to ExpressJS for some reason.

If I curl http://localhost:8080 it always gives me the default Nginx page instead of ExpressJS app home page.

Please advise!

// docker-compose.yml

version: '2.3'

    image: nginx:1.13.8
      - ./nginx/nginx.conf:/etc/nginx/nginx.conf:ro
      - "8080:80"

    build: ./app/

// Nginx config

user  nginx;
worker_processes  1;

error_log  /var/log/nginx/error.log warn;
pid        /var/run/;

events {
    worker_connections  1024;

http {
    include       /etc/nginx/mime.types;
    default_type  application/octet-stream;

    log_format  main  '$remote_addr - $remote_user [$time_local] "$request" '
                      '$status $body_bytes_sent "$http_referer" '
                      '"$http_user_agent" "$http_x_forwarded_for"';

    access_log  /var/log/nginx/access.log  main;

    sendfile        on;
    keepalive_timeout 65;

    # Gzip Settings
    gzip on;
    gzip_proxied any;
    gzip_types text/plain application/json;
    gzip_min_length 1000;

    server {
      listen 80;
      server_name localhost;
      access_log /var/log/nginx/app.log;

      location / {
        proxy_pass http://app:3000;
        proxy_http_version 1.1;
        proxy_set_header Upgrade $http_upgrade;
        proxy_set_header Connection 'upgrade';
        proxy_set_header Host $host;
        proxy_cache_bypass $http_upgrade;

Check that your volume is properly mounted ; what do you see when you do docker-compose exec web cat /etc/nginx/nginx.conf?