nginx 怎么配置二级域名自动跳转到对应子路径上？中间用了 uwsgi、gunicorn 的 web 服务

nginx + uwsgi/gunicorn + app

希望把 xxx.example.com 自动跳转到 example.com/xxx 路径上去，需要把 xxx 的值传到 location 的 gateway 里面去吗？

    server {
    listen 80;
    server_name example.com;
    rewrite ^/(.*)$ permanent;

    location / {
        proxy_pass http://127.0.0.1:8077;
        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;
    }

    location /static/ {
        root /usr/share/nginx/project/app/;
    }

    }