zoukankan      html  css  js  c++  java
  • 【架构】Nginx如何设置X-Request-ID请求头,记录请求时间:毫秒?

    Nginx is awesome, but it’s missing some common features. For instance, a common thing to add to access logs is a unique ID per request, so that you can track the flow of a single request through multiple services. Another thing it’s missing is the ability to log request_time in milliseconds, rather than seconds with a millisecond granularity. Using Lua, we can add these features ourselves.

    I’ll show the whole solution, then I’ll break it down into parts:

    http {
    ...
    
            map $host $request_time_ms {
                default '';
            }
            map $host $uuid {
                default '';
            }
    
            lua_package_path '/etc/nginx/uuid4.lua';
            init_by_lua '
                uuid4 = require "uuid4"
                math = require "math"
            ';
    
            log_by_lua '
              ngx.var.request_time_ms = math.floor(tonumber(ngx.var.request_time) * 1000)
            ';
    
            log_format mycustomformat '[$time_local] "$request" $status $request_length $bytes_sent $request_time_ms $uuid';
            access_log /var/log/nginx/access.log mycustomformat;
    
    ...
    }
    
    server {
    ...
    
      set_by_lua $uuid '
        if ngx.var.http_x_request_id == nil then
            return uuid4.getUUID()
        else
            return ngx.var.http_x_request_id
        end
      ';
    
    ...
    }
    

    It’s necessary to set variables before we use them in Lua. Using map is a trick to set variables in the http context (you can’t use set $variable ” in http). For the case of uuid, we are going to set it in the server section (during the rewrite context), but in case it’s not set, we want to avoid throwing errors. Here’s how we set these variables:

            map $host $request_time_ms {
                default '';
            }
            map $host $uuid {
                default '';
            }
    

    Next we add a uuid4 library to our path, and include the libraries into our context:

            lua_package_path '/etc/nginx/uuid4.lua';
            init_by_lua '
                uuid4 = require "uuid4"
                math = require "math"
            ';
    

    Using the log_by_lua function, we’ll set the request_time_ms variable we’ll use in the log_format config. This Lua function is called in the log context, before logs are written, allowing us to make the variables available to it:

            log_by_lua '
                ngx.var.request_time_ms = math.floor(tonumber(ngx.var.request_time) * 1000)
            ';
    

    Next we set the log format, and use it for the access log:

            log_format mycustomformat '[$time_local] "$request" $status $request_length $bytes_sent $request_time_ms $uuid';
            access_log /var/log/nginx/access.log mycustomformat;
    

    Lastly, we set the uuid during the rewrite context in the server section, using set_by_lua. To facilitate following a request across services, we’ll reuse the header if it’s already set. If the header isn’t set, then this request didn’t come from another service, so we’ll generate a UUID:

    server {
    ...
    
      set_by_lua $uuid '
        if ngx.var.http_x_request_id == nil then
            return uuid4.getUUID()
        else
            return ngx.var.http_x_request_id
        end
      '
    
    ...
    }
    

    If you’re trusting this header data in any way, you should be sure to filter/restrict that header appropriately so that the client can’t change it.

    Update (Thursday December 11 2014): Edited the post to move the uuid generation into the server section and using set_by_lua, so that the uuid can be set to/from the header to flow through the stacks properly. Shout out to Asher Feldman for working out a better solution with me.

    参考资料:

    Using Lua in Nginx for unique request IDs and millisecond times in logs:http://ryandlane.com/blog/2014/12/11/using-lua-in-nginx-for-unique-request-ids-and-millisecond-times-in-logs/

    Simple nginx lua script to add UUID to each request for end to end request tracking:https://gist.github.com/erikcw/e999e1fb438dbbb91533

    Is there a way to log a per request unique id for nginx?:http://serverfault.com/questions/580394/is-there-a-way-to-log-a-per-request-unique-id-for-nginx

    http://stackoverflow.com/questions/17748735/setting-a-trace-id-in-nginx-load-balancer

    https://github.com/kali/nginx-operationid

  • 相关阅读:
    文件上传之前先进行预览
    代码规范
    ESLint 配置文件 .eslintrc 示例及说明
    JQ ajax全局事件 (个人学习笔记)
    JQ ajax (个人学习笔记)
    js 滚动加载图片(懒加载)实现原理 (个人学习笔记)
    js 正则 (个人学习笔记)
    js 理解闭包 (个人学习笔记)
    js 改变this指向的几种方法(个人学习笔记)
    js 理解this指向(个人学习笔记)
  • 原文地址:https://www.cnblogs.com/junneyang/p/5512369.html
Copyright © 2011-2022 走看看