一、背景
最近為了響應(yīng)公司“降本增效”慨亲，提高資源使用率，我們EDI小組決定要整合edi-db宝鼓、edi-rest刑棵、edi-admin三個(gè)springboot應(yīng)用到一個(gè)云主機(jī)上，通過Nginx反向代理進(jìn)行分流愚铡。最終配置結(jié)果如下圖：
二蛉签、遇到問題
edi-admin應(yīng)用運(yùn)行時(shí)通過HttpClient請(qǐng)求edi-rest模塊提供的Rest時(shí)，會(huì)返回404沥寥。
這些URL經(jīng)驗(yàn)證：1）云主機(jī)上通過curl命令訪問正常碍舍；2）客戶端通過postman訪問正常
三、排查
1. 遠(yuǎn)程debug調(diào)試edi-admin觀察http的請(qǐng)求信息
- 請(qǐng)求URI：
test.edi-rest.jd.com/aaa/bbb
- 請(qǐng)求頭信息如下：
host: test.edi-admin.jd.com,
x-real-ip: 172.22.141.3,
x-forwarded-for: 172.22.141.3,
x-forwarded-proto: http,
connection: close,
user-agent: Mozilla/5.0 (X11; Ubuntu; Linux x86_64; rv:84.0) Gecko/20100101 Firefox/84.0,
accept: text/html, */*; q=0.01,
accept-language: en-US,en;q=0.5,
accept-encoding: gzip, deflate,
x-requested-with: XMLHttpRequest,
referer: http://test.edi-admin.jd.com/systemComfig,
cookie: xxxxxx,
Content-Type: application/json;charset=utf-8
2. 觀察nginx的access.log
- curl請(qǐng)求對(duì)應(yīng)日志
127.0.0.1 - - [15/Jan/2021:12:48:12 +0800] "GET /organize/query HTTP/1.1" 302 0 "-" "curl/7.29.0"
127.0.0.1 - - [15/Jan/2021:12:49:16 +0800] "GET /organize/query HTTP/1.1" 302 0 "-" "curl/7.29.0"
127.0.0.1 - - [15/Jan/2021:12:49:28 +0800] "GET /organize/query HTTP/1.1" 200 70 "-" "curl/7.29.0"
- 客戶端Postman請(qǐng)求對(duì)應(yīng)日志
172.22.141.3 - - [15/Jan/2021:15:07:47 +0800] "GET /organize/query HTTP/1.1" 200 70 "-" "PostmanRuntime/7.26.8"
- edi-admin請(qǐng)求日志
127.0.0.1 - - [15/Jan/2021:12:57:44 +0800] "GET /organize/query HTTP/1.1" 404 254 "http://test.edi-admin.jd.com/systemComfig" "Mozilla/5.0 (X11; Ubuntu; Linux x86_64; rv:84.0) Gecko/20100101 Firefox/84.0"
127.0.0.1 - - [15/Jan/2021:12:58:09 +0800] "GET /organize/query HTTP/1.1" 404 252 "http://test.edi-admin.jd.com/systemComfig" "Mozilla/5.0 (X11; Ubuntu; Linux x86_64; rv:84.0) Gecko/20100101 Firefox/84.0"
3. 猜測(cè)驗(yàn)證
猜測(cè)應(yīng)該是edi-admin在請(qǐng)求時(shí)的請(qǐng)求頭和正常有區(qū)別邑雅。經(jīng)過postman驗(yàn)證發(fā)現(xiàn)片橡，是由于edi-admin請(qǐng)求的Header里的host導(dǎo)致的異常。
host: test.edi-admin.jd.com,
四淮野、原因
1）nginx在轉(zhuǎn)發(fā)請(qǐng)求時(shí)會(huì)判斷header里是否有host
如果header里有host捧书，把其作為轉(zhuǎn)發(fā)的目標(biāo)host
否則，使用請(qǐng)求URI的域名host作為轉(zhuǎn)發(fā)的host骤星。
2）驗(yàn)證
postman中加上header：
host: test.edi-admin.jd.com经瓷，復(fù)現(xiàn)404錯(cuò)誤；再此修改header為：
host: test.edi-rest.jd.com洞难，訪問正常舆吮；
3）檢查edi-admin代碼
發(fā)現(xiàn)其在使用httpclient進(jìn)行請(qǐng)求前，把請(qǐng)求edi-admin的header全量復(fù)制給了請(qǐng)求edi-rest的請(qǐng)求里队贱。
private static void copyHeader(HttpServletRequest req, AbstractHttpMessage post) {
Enumeration<String> headers = req.getHeaderNames();
while (headers.hasMoreElements()) {
String name = headers.nextElement();
if (filteredHeader.contains(name.toLowerCase())) {
continue;
}
post.setHeader(name, req.getHeader(name));
}
}
五色冀、解決
修改edi-admin中復(fù)制Header的邏輯，全量復(fù)制改為只復(fù)制Cookie（為了認(rèn)證）柱嫌。重新部署后問題解決呐伞。
