我在服务器上通过ssl运行我的nginx反向代理，域名为：mydomain.com。这在nginx配置下面：

user nginx;
worker_processes auto;
error_log /var/log/nginx/error.log;
pid /run/nginx.pid;

events {
    worker_connections 1024;
}

http {
    include /etc/nginx/mime.types;
    default_type application/octet-stream;
    sendfile on;
    keepalive_timeout 65;

    upstream myApp {
        server my-app:8080;
    }

    server {
        listen 80;
        server_name mydomain.com;
        root /usr/share/nginx/html;
        return 301 https://$host$request_uri;
    }
    server{
        listen 443 ssl;
        root /usr/share/nginx/html;
        server_name mydomain.com;
        include /etc/nginx/mime.types;
        ssl_protocols TLSv1.2 TLSv1.3 TLSv1.1;
        ssl_certificate /etc/nginx/certs/myapp_chain.pem;
        ssl_certificate_key /etc/nginx/certs/private.pem;

        proxy_set_header X-Forwarded-For $proxy_protocol_addr; # To forward the original client's IP address 
        proxy_set_header X-Forwarded-Proto $scheme; # to forward the  original protocol (HTTP or HTTPS)
        proxy_set_header Host $host; # to forward the original host requested by the client
        proxy_buffers 4 256k;
        proxy_buffer_size 128k;
        proxy_busy_buffers_size 256k;

        location / {
            index index.html;
            try_files $uri $uri/ /index.html;
        }

        location /portal {
            proxy_pass http://myApp/;
            proxy_set_header Host $host;
            proxy_set_header X-Real-IP $remote_addr;
        }
    }
}

当我在本地工作时，应用程序运行良好。当我用不同的端口（但不是在nginx后面）运行它时，它可以很好地访问。
问题是当我用mydomain.com/portal访问它时，我得到了这个错误（如图所示）。我允许CORSBTW。
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