title: how to support url with chinese in nginx
body: <p>There are some urls following</p>
  
  <pre><code>domain.com/hashtag/标签
  domain.com/hashtag/tag标签
  domain.com/hashtag/tag
  </code></pre>
  
  <p>in nginx, i use rewrite</p>
  
  <pre><code>if (!-e $request_filename){
     rewrite (*UTF8)^/hashtag/([A-Za-z0-9_]+)$ /hashtag.php?hashtag=$1;
  }
  charset utf-8;
  </code></pre>
  
  <p>my system support UTF-8, and all files are in UTF-8, but only the url <code>domain.com/hashtag/tag</code> can work well, the other two urls are 502 bad gateway. How can I fix this error? thanks a lot.</p>