WordPress Docker over NGINX SSL reverse proxy doesn't work as expected

Question

When I use NGINX to create a reverse proxy for a WordPress Docker container, WordPress specifies WordPress Address (URL) and Site Address (URL) to be https://hiddenurl.com:443. So all my links contain the port 443, and if I delete this port, the website is no longer accessible due to an infinite redirect loop.

I have entered in the wp-config.php that SSL should be activated via $_SERVER['HTTPS'] = 'on';.

NGINX Config:

    location ~ /(?<wppath>.*) {
        rewrite ^/(.*) /$1 break;
        client_max_body_size 100M;
        proxy_pass http://127.0.0.1:7676/$wppath$is_args$args;
        proxy_http_version 1.1;
        proxy_set_header Host $host:$server_port;
        proxy_set_header X-Real-IP $remote_addr;
        proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
        proxy_set_header X-forwarded protocol https;
        proxy_set_header upgrade $http_upgrade;
        proxy_set_header Connection "upgrade
    }

This causes the domain hiddenurl.com to work, but hiddenurl.com/about does redirect to 127.0.0.1/about.

The redirect seems to come from WordPress:

Answer 1

I solved it by using this as an nginx config:

    location / {
        proxy_pass         http://127.0.0.1:7676;
        proxy_redirect     off;
        proxy_set_header   Host $host;
        proxy_set_header   X-Real-IP $remote_addr;
        proxy_set_header   X-Forwarded-For $proxy_add_x_forwarded_for;
        proxy_set_header   X-Forwarded-Host $server_name;
        proxy_set_header   X-Forwarded-Proto https;
        proxy_http_version 1.1;
        proxy_set_header Upgrade $http_upgrade;
        proxy_set_header Connection "upgrade";
        proxy_read_timeout 86400;

      }

And append this to the top of wp-config.php

if ($_SERVER['HTTP_X_FORWARDED_PROTO'] === 'https')
    $_SERVER['HTTPS'] = '1';

if (isset($_SERVER['HTTP_X_FORWARDED_HOST'])) {
    $_SERVER['HTTP_HOST'] = $_SERVER['HTTP_X_FORWARDED_HOST'];
}