Nginx forward to 80

nginx.conf

# Forward http://127.0.0.1:8080 to example.com/
#         http://127.0.0.1:8081 to example.com/foo/
server {
    listen 80;
    server_name example.com;

    location / {
        proxy_pass http://127.0.0.1:8080/;
        proxy_http_version 1.1;
        proxy_set_header Upgrade $http_upgrade;
        proxy_set_header Connection "Upgrade";
    }
    
    # The slash in proxy_pass matters, see https://serverfault.com/questions/379675/nginx-reverse-proxy-url-rewrite
    location /foo/ {
        proxy_pass http://127.0.0.1:8081/;
        proxy_http_version 1.1;
        proxy_set_header Upgrade $http_upgrade;
        proxy_set_header Connection "Upgrade";
    }
}