can't connect rails puma server with nginx reverse proxy - ruby-on-rails

Question

Hello I am trying to setup a reverse proxy with nginx and docker container rails app, public static files are served correctly but can not access to my app. the nginx error log says:
2018/12/08 16:46:45 [error] 4093#4093: *350 could not find named location "#puma", client: xx.xxx.xxx.xx, server: my.app, request: "GET /en/users/sign_in HTTP/2.0",host: "my.app", referrer: "https://my.app/"
my nginx config is this:
upstream puma {
server 0.0.0.0:3000;
}
server {
listen 443 ssl http2;
listen [::]:443 ssl http2;
server_name my.app;
root /var/www/myapp/public;
# SSL
ssl_certificate /etc/letsencrypt/live/my.app/fullchain.pem;
ssl_certificate_key /etc/letsencrypt/live/my.app/privkey.pem;
ssl_trusted_certificate /etc/letsencrypt/live/my.app/fullchain.pem;
include snippets/letsencrypt.conf;
include snippets/ssl.conf;
# reverse proxy
location / {
proxy_pass http://puma; # => http://0.0.0.0:3000
proxy_set_header Host $http_host; # => $host
proxy_set_header X-Forwarded-Proto $scheme; # => "https"
proxy_set_header X-Forwarded-Host $host; # => 0.0.0.0
proxy_set_header X-Forwarded-Port $server_port; # => 3000
proxy_http_version 1.1;
proxy_set_header Upgrade $http_upgrade;
proxy_set_header Connection "upgrade";
proxy_set_header X-Real-IP $remote_addr;
proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
proxy_cache_bypass $http_upgrade;
# index fallback
try_files $uri $uri/ /index.html;
}
# . files
location ~ /\. {
deny all;
}
# assets, media
location ~* \.(?:css(\.map)?|js(\.map)?|jpe?g|png|gif|ico|cur|heic|webp|tiff?)$ {
expires 7d;
access_log off;
}
# svg, fonts
location ~* \.(?:svgz?|ttf|ttc|otf|eot|woff2?)$ {
add_header Access-Control-Allow-Origin "*";
expires 7d;
access_log off;
}
# gzip
gzip on;
gzip_vary on;
gzip_proxied any;
gzip_comp_level 6;
gzip_types text/plain text/css text/xml application/json application/javascript application/xml+rss application/atom+xml image/svg+xml;
# error pages
error_page 500 502 503 504 /50x.html;
location = /50x.html {
root /var/www/myapp/public;
}
error_page 404 /404.html;
location = /404.html {
root /var/www/myapp/public;
}
}
# subdomains redirect
server {
listen 443 ssl http2;
listen [::]:443 ssl http2;
server_name _ *.my.app;
# SSL
ssl_certificate /etc/letsencrypt/live/my.app/fullchain.pem;
ssl_certificate_key /etc/letsencrypt/live/my.app/privkey.pem;
ssl_trusted_certificate /etc/letsencrypt/live/my.app/chain.pem;
include snippets/letsencrypt.conf;
include snippets/ssl.conf;
return 301 https://my.app$request_uri;
}
# HTTP redirect
server {
listen 80;
listen [::]:80;
server_name _ .my.app my.app;
include snippets/letsencrypt.conf;
return 301 https://my.app$request_uri;
}
the rails container start thru docker-compose with this setup:
version: '3.2'
services:
web:
command: rails server -p '3000' -b '0.0.0.0' -e production
ports:
- '3000:3000'
I have tried also with unix socket to connect puma and nginx without success