無(wú)法判斷是否 https 請(qǐng)求

http 網(wǎng)站升級(jí) https 
在 https 狀態(tài)下打印 $_SERVER
  ["REQUEST_SCHEME"] => string(4) "http"
  ["SERVER_PROTOCOL"] => string(8) "HTTP/1.0"

等信息全是http,這是什么原因??

先謝謝大家回答，我的 $_server 全部都沒(méi)有標(biāo)識(shí)https;附上我的nginx 配置

server {
        listen       80;
        root /www;
        server_name xx.com;
        rewrite ^(.*)$  https://$host$1 permanent;
        index  index.html index.php index.htm;
        location ~ \.php$ {
                proxy_pass http://127.0.0.1:88;
                include naproxy.conf;
        }
        location ~ /\.ht {
                deny  all;
        }
        location / {
                try_files $uri @apache;
        }
        location @apache {
                 internal;
                 proxy_pass http://127.0.0.1:88;
                 include naproxy.conf;
        }
}

server {
        listen       443;
        root /www;
        ssl                  on;
        ssl_certificate      cert/xx.com.crt;
        ssl_certificate_key  cert/xx.com.key;
        ssl_prefer_server_ciphers on;
        ssl_session_timeout 10m;
        ssl_protocols TLSv1 TLSv1.1 TLSv1.2;
        server_name xx.com;
        index  index.html index.php index.htm;
        location ~ \.php$ {
                proxy_pass http://127.0.0.1:88;
                include naproxy.conf;
        }
        location ~ /\.ht {
                deny  all;
        }
        location / {
                try_files $uri @apache;
        }
        location @apache {
                 internal;
                 proxy_pass http://127.0.0.1:88;
                 include naproxy.conf;
        }
}