does anyone have a solution for me to access a subfolder of my application behind nginx proxy?

I have two servers with different IP addresses:

• Tomcat serving my webapp https://app1.domain.com (centos6)
• Nginx acting as waf via https://nginx.domain.com (centos7)

Nginx is running on port 443, and I'm using it to reverse proxy my webapp this way:

location /app1/ {
    rewrite ^/app1(.*) /$1 break; 
    proxy_pass https://app1.domain.com/;
}

This way, I normally access my webapp via nginx through https://nginx.domain.com/app1/.

Secondly, in the ROOT folder of my webapp, I installed the birt-viewer application in the ROOT/birt-viewer folder. I normally access the birt-viewer application when I use the link https://app1.domain.com/birt-viewer.

However, I don't normally access the birt application when I use the link https:// nginx.domain.com/app1/birt-viewer. When I copy for example the link

/birt-viewer/Task.jsp?__report=Recare.rpgn&sample=my+parameter&__sessionId=2026

and I paste it after the link https://nginx.domain.com/app1 to obtain the final link

https://nginx.domain.com/app1/birt-viewer/Task.jsp?__report=Recare.rpgn&sample=my+parameter&__sessionId=2026

I access the birt-viewer application but I lose settings such as cookies and sessions.

You understand that to access my webapp via nginx I have to do it manually; the disadvantage is the loss of cookies, sessions and other parameters. Yet access should be done automatically without problems.

This is my nginx config:

user nginxxxx;
worker_processes  1;
error_log /var/log/error.log warn;
pid        logs/nginx.pid;
events {
    worker_connections  1024;
}
http {
#    include mime.types;
    include /opt/nginx/conf/mime.types;    
    include /opt/nginx/conf/naxsi_core.rules;
    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/access.log main;
    sendfile        on;
    tcp_nopush     on;
    keepalive_timeout  65;
    tcp_nodelay on;
    gzip  on;
    gzip_disable "MSIE [1-6].(?!.*SV1)";
    client_max_body_size 100m;
    client_body_buffer_size 10K;

    server {
         listen 443 ssl;
        server_name nginx.domain.com;
    access_log on ;
        access_log /var/log/access.log main;
    error_log on ;
        error_log /var/log/error.log warn;
        ssl_certificate /etc/ssl/certs/m.crt;
        ssl_certificate_key /etc/ssl/private/cs.key;
        ssl_protocols TLSv1.2 TLSv1.3;
        ssl_ciphers  HIGH:!aNULL:!MD5;
        ssl_prefer_server_ciphers  on;
        add_header Strict-Transport-Security "max-age=63072000; includeSubdomains;" always;
        add_header X-Frame-Options SAMEORIGIN;
        add_header X-Content-Type-Options nosniff;
        add_header X-XSS-Protection "1; mode=block";
    error_page 403 /403_error.html;
        location = /403_error.html {
            root /usr/share/nginx/htmml;
            internal;
        }

    error_page 404 /404_error.html;
        location = /404_error.html {
            root /usr/share/nginx/html;
            internal;
        }


 location /app1/
         {
rewrite ^/app1(.*) /$1 break;
proxy_connect_timeout 60000;
proxy_send_timeout 60000;
proxy_read_timeout 60000;
send_timeout 60000;
proxy_pass https://app1.domain.com/;
   }

location /app1/birt-viewer/ {
    rewrite ^/app1/folder1(.*) /$1 break; 
    proxy_pass https:// app1.domain.com/birt-viewer/;
}

           }

}

I also realize that once my webapp behind nginx, some urls are not up to date and still keep the old access.

So my concern is to access the birt-viewer application automatically (not manually) through nginx via https://nginx.domain.com/app1/birt-viewer

Does anyone have a solution for me?