reverse proxy to gist

gist.conf

# server, gist reverse proxy
server {
    listen  80;
    server_name gist.oyohyee.com;
    access_log  off;
    resolver    8.8.8.8;
    location / {
        proxy_pass          https://gist.github.com;
        proxy_cache_valid   200 302 1h;
        proxy_cache_valid   404 1m;
        proxy_cache_use_stale error timeout invalid_header updating http_500 http_502 http_503 http_504;
        proxy_set_header    Accept-Encoding "";
        proxy_set_header    Accept-Language "zh-CN";
        proxy_set_header    User-Agent $http_user_agent;
        sub_filter  https://gist-assets.github.com/ http://gist.oyohyee.com/;
        sub_filter  https://gist.github.com/ http://gist.oyohyee.com/;
        sub_filter  https://github.com/ http://gist.oyohyee.com/;
        sub_filter_once     off;
    }
}
# server, gist reverse proxy
server {
    listen  443 ssl http2 default_server;
    server_name gist.oyohyee.com;
    access_log  off;
    resolver    8.8.8.8;

    ssl_certificate "/etc/nginx/ssl/1_gist.oyohyee.com_bundle.crt";
    ssl_certificate_key "/etc/nginx/ssl/2_gist.oyohyee.com.key";
    ssl_session_cache shared:SSL:1m;
    ssl_session_timeout  10m;
    ssl_ciphers HIGH:!aNULL:!MD5;
    ssl_prefer_server_ciphers on;


    location / {
        proxy_pass          https://gist.github.com;
        proxy_cache_valid   200 302 1h;
        proxy_cache_valid   404 1m;
        proxy_cache_use_stale error timeout invalid_header updating http_500 http_502 http_503 http_504;
        proxy_set_header    Accept-Encoding "";
        proxy_set_header    Accept-Language "zh-CN";
        proxy_set_header    User-Agent $http_user_agent;
        sub_filter  https://gist-assets.github.com/ http://gist.oyohyee.com/;
        sub_filter  https://gist.github.com/ http://gist.oyohyee.com/;
        sub_filter  https://github.com/ http://gist.oyohyee.com/;
        sub_filter_once     off;
    }
}