序
本文主要來聊一下nginx的access log當中出現的499問題。
問題描述
499 CLIENT CLOSED REQUEST
A non-standard status code introduced by nginx for the case when a client closes the connection while nginx is processing the request.
原因
伺服器返回http頭之前，客戶端就提前關閉了http連線，常見於後臺介面處理時間比較長，而前端請求又自帶有超時時間。
復現
請求例項
<!DOCTYPE html>
<html>
<head>
<script src="http://www.w3school.com.cn/jquery/jquery-1.11.1.min.js"></script>
<script>
$(document).ready(function(){
$("button").click(function(){
$.ajax({
url : `/demo/test`,
timeout : 10000,
type : `get`,
dataType : `json`,
success : function(data){
alert(`success`);
}
});
});
});
</script>
</head>
<body>
<button>ajax帶超時時間請求</button>
</body>
</html>後臺介面
@GetMapping("/test")
public String test(HttpServletResponse response) throws InterruptedException {
Thread.sleep(100*1000);
return "hello";
}nginx
location /demo/ {
access_log /usr/local/var/log/nginx/host.access.log main;
proxy_pass http://localhost:8080/demo/ ;
}關於log format如下
log_format main `$remote_addr - $remote_user [$time_local] "$request" `
`$status $body_bytes_sent "$http_referer" `
`"$http_user_agent" "$http_x_forwarded_for"`;log例項
127.0.0.1 - - [04/Nov/2017:01:11:29 +0800] "GET /demo/test HTTP/1.1" 499 0 "http://localhost:8888/demo.html" "Mozilla/5.0 (Macintosh; Intel Mac OS X 10_11_5) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/61.0.3163.100 Safari/537.36" "-"
127.0.0.1 - - [04/Nov/2017:01:11:42 +0800] "GET /demo/test HTTP/1.1" 499 0 "http://localhost:8888/demo.html" "Mozilla/5.0 (Macintosh; Intel Mac OS X 10_11_5) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/61.0.3163.100 Safari/537.36" "-"
127.0.0.1 - - [04/Nov/2017:01:11:58 +0800] "GET /demo/test HTTP/1.1" 499 0 "http://localhost:8888/demo.html" "Mozilla/5.0 (Macintosh; Intel Mac OS X 10_11_5) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/61.0.3163.100 Safari/537.36" "-"