You cannot select more than 25 topics Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.

522 lines
25 KiB
Markdown

2 years ago
# 22 | 压测平台:如何解决 GoReplay 动态数据关联?
你好,我是高楼。
在第 6 讲,我们说过目前主流的流量回放工具都无法轻易解决 session 的问题,所以从系统安全的角度来说,工具需要做对应的改造。
这节课,我们来聊一下 GoReplay 如何通过改造解决回放过程中动态数据关联的问题。
## 关联是什么?
我们可以把关联简单地理解为把服务端返回的某个值传递给后续的调用使用。我们可以在很多场景用到它。举个例子我们常见的“Session ID”就是一个典型的需要关联的数据。它需要在交互过程中标识一个客户端身份这个身份要在后续的调用中一直存在否则服务端就不认识这个客户端了。
对每一个性能测试工具来说关联是应该具备的基本功能GoReplay 也不例外。
但是有很多新手同学对关联的逻辑并不是十分理解,甚至有人觉得关联和参数化(流量数据)是一样的,因为它们用的都是动态的数据,并且关联过来的数据也可以用到参数化(流量数据)中。其实,这二者还是有所不同的,因为关联的数据后续脚本中会用到,但参数化就不会。
现在有很多全链路压测都是由单接口基准创建的,这样一来,关联就用得比较少。因为接口级的基准场景都是一发一收就结束了,不需要将数据保存下来再发送出去。
那么正常情况下,什么样的场景需要关联呢?一般情况下, 它们需要满足下面几个条件:
1. 数据是由服务器端生成的;
2. 数据在每一次请求时都是动态变化的;
3. 数据在后续的请求中需要再发送出去。
你可以通过这张示意图加深一下理解:
![图片](https://static001.geekbang.org/resource/image/6f/62/6f28747510866b140821bfd83ea9bb62.jpg?wh=1264x802)
好了,我们知道了关联的基本概念和适用场景,那么在 GoReplay 中又如何改造呢?
作为一款流量回放工具我们知道GoReplay的核心原理就是基于流量文件去倍数回放请求。很显然这个流量文件是个死的东西是不能动态参数数据的那么我们又该怎么办呢
这时候,我们就需要搬出 GoReplay 的中间件了。
## 中间件是什么?
[中间件](https://github.com/buger/goreplay/wiki/middleware) [Middleware](https://github.com/buger/goreplay/wiki/middleware) )是一个在 STDIN标准输入 接收请求、响应 payload (有效请求负载)并在 STDOUT标准输出 发出修改请求的程序。你可以在中间件上实现任何自定义逻辑,比如认证、复杂的重写和筛选请求等。
通过传入 Middleware 参数,我们可以发送命令给 GoReplayGoReplay 会拉起一个进程执行这个命令。在录制过程中GoReplay 通过获取进程的 STDIN 和 STDOUT 与输入输出插件进程进行通信,中间件内部逻辑为 STDERR数据流向大致如下
```bash
Original request +--------------+
+-------------+----------STDIN---------->+ |
| Gor input | | Middleware |
+-------------+----------STDIN---------->+ |
Original response +------+---+---+
| ^
+-------------+ Modified request v |
| Gor output +<---------STDOUT-----------------+ |
+-----+-------+ |
| |
| Replayed response |
+------------------STDIN----------------->----+
```
需要注意的是,如果希望记录原始响应和回放响应,不要忘记添加 ** output-http-track-response** 和 ** input-raw-track-response** 参数。
GoReplay 支持用任何语言编写中间件的协议,同时中间件程序还需要格外注意一点,就是中间件和 Gor 的所有通信都是异步,因此,我们不能保证原始请求和响应消息会一个接一个地出现。如果业务逻辑依赖于原始响应或回放响应,那么中间件应用程序就应该处理好状态,也就是要做好动态数据的处理动作。
为了简化中间件的功能实现,官方为 [node.js](https://github.com/buger/goreplay/tree/master/middleware) 和 Go (即将推出)提供了包。
## 如何使用中间件?
那么,应该怎样使用中间件呢?
下面就是一个简单的使用 bash echo 中间件的示例,我们用它来打印对应的 payload 类型:
```
#!/usr/bin/env bash
#
# `xxd` utility included into vim-common package
# It allow hex decoding/encoding
#
# This example may broke if you request contains `null` string, you may consider using pipes instead.
# See: https://github.com/buger/gor/issues/309
#
function log {
# Logging to stderr, because stdout/stdin used for data transfer
# 记录到 stderr因 为 stdout/stdin 用于数据传输
>&2 echo "[DEBUG][ECHO] $1"
}
while read line; do
decoded=$(echo -e "$line" | xxd -r -p)
header=$(echo -e "$decoded" | head -n +1)
payload=$(echo -e "$decoded" | tail -n +2)
encoded=$(echo -e "$header\n$payload" | xxd -p | tr -d "\\n")
log ""
log "==================================="
case ${header:0:1} in
"1")
log "Request type: Request"
;;
"2")
log "Request type: Original Response"
;;
"3")
log "Request type: Replayed Response"
;;
*)
log "Unknown request type $header"
esac
echo "$encoded"
log "==================================="
log "Original data: $line"
log "Decoded request: $decoded"
log "Encoded data: $encoded"
done;
```
这里我们使用【会员登录接口】来做演示。
![图片](https://static001.geekbang.org/resource/image/yy/18/yy0d0a5afb7e1a295c0e10b94b989518.png?wh=1282x941)
首先,通过指定 Middleware 可执行文件的命令,也就是使用 Middleware 参数在 GoReplay 启用中间件功能:
```bash
sudo ./goreplay --input-raw :8081 --middleware "./echo.sh" --output-http "http://staging.server"
```
接下来,我们通过 Postman 对【会员登录】接口做一次测试。
![图片](https://static001.geekbang.org/resource/image/0c/c4/0cd47ef4bfd1b47513bc36d312db33c4.png?wh=633x479)
通过控制台我们看到,中间件程序已经成功把经过的流量信息全部打印出来了。
```bash
Interface: en0 . BPF Filter: ((tcp dst port 8081) and (dst host fe80::8f6:ee40:ebd1:bec or dst host 192.168.3.58))
Interface: awdl0 . BPF Filter: ((tcp dst port 8081) and (dst host fe80::50a5:ceff:feeb:47e3))
Interface: llw0 . BPF Filter: ((tcp dst port 8081) and (dst host fe80::50a5:ceff:feeb:47e3))
Interface: utun0 . BPF Filter: ((tcp dst port 8081) and (dst host fe80::d9a3:ab1b:f8e4:4de))
Interface: utun1 . BPF Filter: ((tcp dst port 8081) and (dst host fe80::c2a0:19a0:9d9d:6699))
Interface: utun2 . BPF Filter: ((tcp dst port 8081) and (dst host fe80::771:4985:8642:7857))
Interface: utun3 . BPF Filter: ((tcp dst port 8081) and (dst host fe80::4a93:e598:6e37:37b3))
Interface: lo0 . BPF Filter: ((tcp dst port 8081) and (dst host 127.0.0.1 or dst host ::1 or dst host fe80::1))
2021/11/14 17:16:34 [PPID 8021 and PID 8022] Version:1.3.0
[DEBUG][ECHO]
[DEBUG][ECHO] ===================================
[DEBUG][ECHO] Request type: Request
[DEBUG][ECHO] ===================================
[DEBUG][ECHO] Original data: 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
[DEBUG][ECHO] Decoded request: 1 cb9f1f910000000155599937 1636881399760637000 0
POST /admin/login HTTP/1.1
Content-Type: application/json
Authorization: true
User-Agent: PostmanRuntime/7.28.4
Accept: */*
Postman-Token: 4fa25e6b-fd46-4e96-8af6-f6c5ba0f003f
Host: localhost:8081
Accept-Encoding: gzip, deflate, br
Connection: keep-alive
Content-Length: 52
{
"password": "123456",
"username": "test"
}
[DEBUG][ECHO] Encoded data: 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
```
到这里,我们已经了解了中间件的基本功能和使用方法,接下来我们回到这节课的主题,如何实现关联操作?
## 如何实现回放关联?
这里我们引入“会员登录”和“查询所有后台资源分类”两个接口为例。
你可以先看看这张整体的请求交互示意图:
![图片](https://static001.geekbang.org/resource/image/8d/ce/8da2fa743c61455yyd80f63ebe1e18ce.jpg?wh=1424x1953)
* 会员登录
![图片](https://static001.geekbang.org/resource/image/yy/18/yy0d0a5afb7e1a295c0e10b94b989518.png?wh=1282x941)
* 查询所有后台资源分类
![图片](https://static001.geekbang.org/resource/image/1a/d8/1a1dbcd1f3eb0566308bfed7fa03efd8.png?wh=1296x754)
我们知道 token 是有时效的,如果失效,那么二次请求服务端校验就会失败。如下图:
![图片](https://static001.geekbang.org/resource/image/b2/96/b20756aca3d9886966984da4096ee596.png?wh=1244x795)
下面我们具体来演示下如何解决token关联的问题。
第一步,创建一个流量录制的命令:
```shell
#!/bin/bash
PORT="8081"
OUT_FILE="request.gor"
sudo ./goreplay --input-raw :$PORT --output-file=$OUT_FILE -output-file-append --input-raw-track-response --prettify-http
```
录制下的流量文件如下:
```shell
1 d1ae1f9100000001e404ee86 1635588156669182000 0
POST /admin/login HTTP/1.1
Content-Type: application/json
Authorization: true
User-Agent: PostmanRuntime/7.28.4
Accept: */*
Postman-Token: 480f15ca-53df-44fd-8980-5e9118b2107e
Host: localhost:8081
Accept-Encoding: gzip, deflate, br
Connection: keep-alive
Content-Length: 52
{
"password": "123456",
"username": "test"
}
🐵🙈🙉
2 d1ae1f9100000001e404ee86 1635588156828973000 458000
HTTP/1.1 200
Content-Length: 254
Vary: Origin
Vary: Access-Control-Request-Method
Vary: Access-Control-Request-Headers
X-Content-Type-Options: nosniff
X-XSS-Protection: 1; mode=block
Cache-Control: no-cache, no-store, max-age=0, must-revalidate
Pragma: no-cache
Expires: 0
X-Frame-Options: DENY
Content-Type: application/json
Date: Sat, 30 Oct 2021 10:02:36 GMT
Keep-Alive: timeout=60
Connection: keep-alive
{"code":200,"message":"操作成功","data":{"tokenHead":"","token":"eyJhbGciOiJIUzUxMiJ9.eyJzdWIiOiJ0ZXN0IiwiY3JlYXRlZCI6MTYzNTU4ODE1Njc5NCwiZXhwIjoxNjM1NTg4MjE2fQ.-wsZa0gijz2KfCF-eAYK1Tt-pd_vw2_LShShlIDCQOsHjOZZlGl8yX2MncZlO9St_oPj1JdBaERjfEU6iu12qw"}}
🐵🙈🙉
1 d1ae1f9100000001e405029a 1635588192031592000 0
GET /resource/listAll HTTP/1.1
token: eyJhbGciOiJIUzUxMiJ9.eyJzdWIiOiJ0ZXN0IiwiY3JlYXRlZCI6MTYzNTU4ODE1Njc5NCwiZXhwIjoxNjM1NTg4MjE2fQ.-wsZa0gijz2KfCF-eAYK1Tt-pd_vw2_LShShlIDCQOsHjOZZlGl8yX2MncZlO9St_oPj1JdBaERjfEU6iu12qw
User-Agent: PostmanRuntime/7.28.4
Accept: */*
Postman-Token: 4bc2152e-dbd4-4b2a-b880-72ed5ee4303a
Host: localhost:8081
Accept-Encoding: gzip, deflate, br
Connection: keep-alive
🐵🙈🙉
2 d1ae1f9100000001e405029a 1635588192064563000 1084000
HTTP/1.1 200
Content-Length: 3997
Vary: Origin
Vary: Access-Control-Request-Method
Vary: Access-Control-Request-Headers
X-Content-Type-Options: nosniff
X-XSS-Protection: 1; mode=block
Cache-Control: no-cache, no-store, max-age=0, must-revalidate
Pragma: no-cache
Expires: 0
X-Frame-Options: DENY
Content-Type: application/json
Date: Sat, 30 Oct 2021 10:03:12 GMT
Keep-Alive: timeout=60
Connection: keep-alive
{"code":200,"message":"操作成功","data":[{"id":1,"createTime":"2020-02-04T09:04:55.000+00:00","name":"商品品牌管理","url":"/brand/**","description":null,"categoryId":1},{"id":2,"createTime":"2020-02-04T09:05:35.000+00:00","name":"商品属性分类管理","url":"/productAttribute/**","description":null,"categoryId":1},{"id":3,"createTime":"2020-02-04T09:06:13.000+00:00","name":"商品属性管理","url":"/productAttribute/**","description":null,"categoryId":1},{"id":4,"createTime":"2020-02-04T09:07:15.000+00:00","name":"商品分类管理","url":"/productCategory/**","description":null,"categoryId":1},{"id":5,"createTime":"2020-02-04T09:09:16.000+00:00","name":"商品管理","url":"/product/**","description":null,"categoryId":1},{"id":6,"createTime":"2020-02-04T09:09:53.000+00:00","name":"商品库存管理","url":"/sku/**","description":null,"categoryId":1},{"id":8,"createTime":"2020-02-05T06:43:37.000+00:00","name":"订单管理","url":"/order/**","description":"","categoryId":2},{"id":9,"createTime":"2020-02-05T06:44:22.000+00:00","name":" 订单退货申请管理","url":"/returnApply/**","description":"","categoryId":2},{"id":10,"createTime":"2020-02-05T06:45:08.000+00:00","name":"退货原因管理","url":"/returnReason/**","description":"","categoryId":2},{"id":11,"createTime":"2020-02-05T06:45:43.000+00:00","name":"订单设置管理","url":"/orderSetting/**","description":"","categoryId":2},{"id":12,"createTime":"2020-02-05T06:46:23.000+00:00","name":"收货地址管理","url":"/companyAddress/**","description":"","categoryId":2},{"id":13,"createTime":"2020-02-07T08:37:22.000+00:00","name":"优惠券管理","url":"/coupon/**","description":"","categoryId":3},{"id":14,"createTime":"2020-02-07T08:37:59.000+00:00","name":"优惠券领取记录管理","url":"/couponHistory/**","description":"","categoryId":3},{"id":15,"createTime":"2020-02-07T08:38:28.000+00:00","name":"限时购活动管理","url":"/flash/**","description":"","categoryId":3},{"id":16,"createTime":"2020-02-07T08:38:59.000+00:00","name":"限时购商品关系管理","url":"/flashProductRelation/**","description":"","categoryId":3},{"id":17,"createTime":"2020-02-07T08:39:22.000+00:00","name":"限时购场次管理","url":"/flashSession/**","description":"","categoryId":3},{"id":18,"createTime":"2020-02-07T08:40:07.000+00:00","name":"首页轮播广告管理","url":"/home/advertise/**","description":"","categoryId":3},{"id":19,"createTime":"2020-02-07T08:40:34.000+00:00","name":"首页品牌管理","url":"/home/brand/**","description":"","categoryId":3},{"id":20,"createTime":"2020-02-07T08:41:06.000+00:00","name":"首页新品管理","url":"/home/newProduct/**","description":"","categoryId":3},{"id":21,"createTime":"2020-02-07T08:42:16.000+00:00","name":"首页人气推荐管理","url":"/home/recommendProduct/**","description":"","categoryId":3},{"id":22,"createTime":"2020-02-07T08:42:48.000+00:00","name":"首页专题推荐管理","url":"/home/recommendSubject/**","description":"","categoryId":3},{"id":23,"createTime":"2020-02-07T08:44:56.000+00:00","name":" 商品优选管理","url":"/prefrenceArea/**","description":"","categoryId":5},{"id":24,"createTime":"2020-02-07T08:45:39.000+00:00","name":"商品专题管理","url":"/subject/**","description":"","categoryId":5},{"id":25,"createTime":"2020-02-07T08:47:34.000+00:00","name":"后台用户管理","url":"/admin/**","description":"","categoryId":4},{"id":26,"createTime":"2020-02-07T08:48:24.000+00:00","name":"后台用户角色管理","url":"/role/**","description":"","categoryId":4},{"id":27,"createTime":"2020-02-07T08:48:48.000+00:00","name":"后台菜单管理","url":"/menu/**","description":"","categoryId":4},{"id":28,"createTime":"2020-02-07T08:49:18.000+00:00","name":"后台资源分类管理","url":"/resourceCategory/**","description":"","categoryId":4},{"id":29,"createTime":"2020-02-07T08:49:45.000+00:00","name":"后台资源管理","url":"/resource/**","description":"","categoryId":4}]}
🐵🙈🙉
```
第二步,创建一个流量回放 Shell 脚本。
```shell
#!/bin/bash
## Usage: ./replay.sh
OUTPUT="http://127.0.0.1:8081"
INPUT_FILE="requests.gor"
sudo ./goreplay --input-file $INPUT_FILE --input-file-loop --output-http=$OUTPUT --prettify-http --output-http-track-response --output-stdout
```
第三步,我们尝试进行一次回放操作。
![图片](https://static001.geekbang.org/resource/image/c8/e4/c8e10a5c7b6621cc54d4971b217959e4.png?wh=750x355)
等待一会,我们看到回放的【查询所有后台资源分类】接口已经失败了,提示 token 失效了。
要怎么解决这个问题呢?
在这种情况下,我们需要实时将来自录制的 token 关联到来自回放响应的 token 上 ,然后使用关联的 token 修改回放的请求。我们使用 GoReplay 存储库中的这个方便的[示例](https://github.com/buger/goreplay/blob/master/examples/middleware/token_modifier.go)进行扩展。
所涉及的基本算法你可以看看下面这张图片。
![](https://static001.geekbang.org/resource/image/c0/00/c0b9bd3a17b2d34f0ec2d4e1ea5f0e00.jpg?wh=1920x1040)
因为原始服务器没有预定义的token而回放服务器有自己的token它不能与原始服务器同步。所以不使用中间件或者中间件只使用请求有效 payload都会使得token失效。
为了解决这个问题,我们的中间件应该考虑回放和源服务器的响应,存储’ originalToken -> replayedToken '别名,并使用此 token 重写所有请求以使用回放别名。
顺着这个思路,我们看下第四步,创建 token 关联中间件程序。
```go
package main
import (
"bufio"
"bytes"
"encoding/hex"
"fmt"
"github.com/bitly/go-simplejson"
"github.com/buger/goreplay/proto"
"os"
)
// requestID -> originalToken
// 请求 ID -> 原始 Token
var originalTokens map[string][]byte
// originalToken -> replayedToken
// 原始 Token -> 回放 Token
var tokenAliases map[string][]byte
var json_data interface{}
func main() {
originalTokens = make(map[string][]byte)
tokenAliases = make(map[string][]byte)
scanner := bufio.NewScanner(os.Stdin)
for scanner.Scan() {
encoded := scanner.Bytes()
buf := make([]byte, len(encoded)/2)
hex.Decode(buf, encoded)
process(buf)
}
}
func process(buf []byte) {
// First byte indicate payload type, possible values:
// 1 - Request
// 2 - Response
// 3 - ReplayedResponse
// 第一个字节表示有效负载类型,可能的值:
// 1 - 请求
// 2 - 响应
// 3 - 回放响应
payloadType := buf[0]
headerSize := bytes.IndexByte(buf, '\n') + 1
header := buf[:headerSize-1]
// Header contains space separated values of: request type, request id, and request start time (or round-trip time for responses)
// Header 包含空格分隔的值:请求类型,请求 id请求开始时间(或响应的往返时间)
meta := bytes.Split(header, []byte(" "))
// For each request you should receive 3 payloads (request, response, replayed response) with same request id
// 对于每个请求,你应该收到 3 个有效负载(request, response, replayed response),具有相同的请求 id
reqID := string(meta[1])
payload := buf[headerSize:]
Debug("Received payload:", string(buf))
switch payloadType {
case '1': // Request
if bytes.Equal(proto.Path(payload), []byte("/admin/login")) {
originalTokens[reqID] = []byte{}
Debug("Found token request:", reqID)
} else {
//token, vs, _ := proto.PathParam(payload, []byte("token")) //取到回放响应的 token 值
token := proto.Header(payload, []byte("token")) //取到原始的 token 值
Debug("Received token:", string(token))
if len(token) != 0 { // If there is GET token param
Debug("If there is GET token param")
Debug("tokenAliases", tokenAliases)
if alias, ok := tokenAliases[string(token)]; ok { //检查要替换的 token 值是否存在
Debug("Received alias")
// Rewrite original token to alias
payload = proto.SetHeader(payload, []byte("token"), alias) //将原始的 token 替换成回放的 token
// Copy modified payload to our buffer
buf = append(buf[:headerSize], payload...)
}
}
}
// Emitting data back
os.Stdout.Write(encode(buf)) //重写请求准备发往回放服务
case '2': // Original response
if _, ok := originalTokens[reqID]; ok {
jsonObject, err := simplejson.NewJson([]byte(proto.Body(payload)))
if err != nil {
fmt.Println(err)
}
result := jsonObject.Get("data")
token := result.Get("token")
secureToken:=token
f ,_:=secureToken.Bytes()
originalTokens[reqID] = f
Debug("Remember origial token:", f)
}
case '3': // Replayed response
if originalToken, ok := originalTokens[reqID]; ok {
delete(originalTokens, reqID)
jsonObject, err := simplejson.NewJson([]byte(proto.Body(payload)))
if err != nil {
fmt.Println(err)
}
result := jsonObject.Get("data")
token := result.Get("token")
f ,_:=token.Bytes()
tokenAliases[string(originalToken)] = f //拿到现在的 token 值用来替换掉过去的 token 值
Debug("Create alias for new token token, was:", string(originalToken), "now:", string(f))
}
}
}
func encode(buf []byte) []byte {
dst := make([]byte, len(buf)*2+1)
hex.Encode(dst, buf)
dst[len(dst)-1] = '\n'
return dst
}
func Debug(args ...interface{}) {
if os.Getenv("GOR_TEST") == "" { // if we are not testing
fmt.Fprint(os.Stderr, "[DEBUG][TOKEN-MOD] ")
fmt.Fprintln(os.Stderr, args...)
}
}
```
我们可以使用 process 函数异步处理原始请求或回放响应从而重新设置 token。由于 GoReplay 的每个三元组(请求、响应、回放响应)共享一个请求 ID因此到达中间件的第一个响应可以将它的 token 关联到请求 ID。当第二个响应到达时我们就可以访问两个 token了。我们可以将原始 token 关联到回放的 token并能够一一对应因为第二个响应类型也可用
好了,这样中间件就写完了,我们一起来测试一下。
我们先创建一个运行中间件的 Shell 脚本 middleware\_wrapper.sh。
```bash
#!/bin/bash
go run token_modifier.go
```
第二步,修改启动回放的 Shell 脚本 replay.sh。
```bash
#!/bin/bash
## Usage: ./replay.sh
OUTPUT="http://127.0.0.1:8081"
MIDDLEWARE="./middleware_wrapper.sh"
INPUT_FILE="requests.gor"
sudo ./goreplay --input-file $INPUT_FILE --input-file-loop --output-http=$OUTPUT --middleware $MIDDLEWARE --prettify-http --output-http-track-response --output-stdout
```
最后一步,我们就要紧盯运行控制台了。
* 登录接口实时返回的 token。
![图片](https://static001.geekbang.org/resource/image/c4/90/c4a97041689054c34c2b721a48ecd190.png?wh=1881x695)
* 【查询所有后台资源分类】接口,可以看到已经成功替换到回放响应的 token了。
![图片](https://static001.geekbang.org/resource/image/de/98/de4c63d1d179f2b5b4804e5febac1898.png?wh=750x386)
* 【查询所有后台资源分类】接口,回放响应的数据也是正常的。
![图片](https://static001.geekbang.org/resource/image/55/24/55b26162d5dacaa39a0a161d5f83f124.png?wh=750x321)
* 服务端日志显示正常。
![图片](https://static001.geekbang.org/resource/image/71/yy/71e8fd0b45f03d5861c1debe0cd504yy.png?wh=599x348)
好了,到这里,我们的动态数据关联功能就已经实现了。
## 总结
好了,这节课就讲到这里。刚才,我们一起梳理了关联的基本概念、 GoReplay 中间件( Middleware 原理、常用的用法。我们还通过例子演示了GoReplay 如何通过扩展 Middleware 做到关联功能。实际上,我们可以在中间件上实现任何自定义逻辑,比如认证、复杂的重写和筛选请求等。
下一节课,我们将进入具体的分布式改造环节,我会通过案例演示如何做分布式平台改造工作。
## 课后题
学完这节课,请你思考两个问题:
1. 你有没有使用过 Middleware谈谈你对 Middleware 应用的一些心得吧!
2. 相比 JMeter你觉得 GoReplay 关联的难度在什么地方?
欢迎你在留言区与我交流讨论。当然了,你也可以把这节课分享给你身边的朋友,他们的一些想法或许会让你有更大的收获。我们下节课见!