My nginx server stanza looks like this. Maybe try putting the proxy_set… params outside of your location {…} stanzas.
server {
listen 443 ssl;
server_name localhost;
ssl_certificate C:/.../nginx/conf/certificate.pem;
ssl_certificate_key C:/.../nginx/conf/key.pem;
proxy_http_version 1.1;
proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
proxy_set_header Host $host;
# streamlit specific:
proxy_set_header Upgrade $http_upgrade;
proxy_set_header Connection "upgrade";
proxy_read_timeout 86400;
location / {
auth_basic "Access Restricted";
auth_basic_user_file C:/.../nginx/conf/.htpasswd;
proxy_pass http://127.0.0.1:8501;
}
}