摘要：用于方便地搭建能夠處理超高并發(fā)擴(kuò)展性極高的動態(tài)應(yīng)用服務(wù)和動態(tài)網(wǎng)關(guān)。

權(quán)限認(rèn)證是接口開發(fā)中不可避免的問題,權(quán)限認(rèn)證包括兩個方面

接口需要知道調(diào)用的用戶是誰

接口需要知道該用戶是否有權(quán)限調(diào)用

第1個問題偏向于架構(gòu)，第2個問題更偏向于業(yè)務(wù)，因此考慮在架構(gòu)層解決第1個問題，以達(dá)到以下目的

所有請求被保護(hù)的接口保證是合法的(已經(jīng)認(rèn)證過的用戶)

接口可以從請求頭中獲取當(dāng)前用戶信息

每個請求都有uuid用于標(biāo)識

JWT(JSON Web Token)目前是應(yīng)用最廣的接口權(quán)限方案，具有無狀態(tài),跨系統(tǒng),多語言多平臺支持等特點，如果能在網(wǎng)關(guān)層實現(xiàn)JWT驗證不僅可以避免代碼入侵還能為整個后臺提供統(tǒng)一的解決方案,目前客戶網(wǎng)關(guān)使用Nginx,但社區(qū)版Nginx中沒有JWT模塊,自己實現(xiàn)不現(xiàn)實,因此選擇OpenResty作為網(wǎng)關(guān)層, 據(jù)官網(wǎng)介紹,OpenResty? 是一個基于 Nginx 與 Lua 的高性能 Web 平臺，其內(nèi)部集成了大量精良的 Lua 庫、第三方模塊以及大多數(shù)的依賴項。用于方便地搭建能夠處理超高并發(fā)、擴(kuò)展性極高的動態(tài) Web 應(yīng)用、Web 服務(wù)和動態(tài)網(wǎng)關(guān)。本質(zhì)上就是一個Nginx+Lua的集成軟件.
整體架構(gòu)如圖：

[root@docker ~]# cat /etc/redhat-release
CentOS Linux release 7.4.1708 (Core)
[root@docker ~]# more /proc/version
Linux version 3.10.0-693.el7.x86_64 (builder@kbuilder.dev.centos.org) (gcc version 4.8.5 20150623 (Red Hat 4.
8.5-16) (GCC) ) #1 SMP Tue Aug 22 21:09:27 UTC 2017

OpenRestry安裝很簡單,可以在這里找到不同版本操作系統(tǒng)安裝文檔,本次使用的環(huán)境是CentOS Linux release 7.4

[root@docker ~]# yum install yum-utils
[root@docker ~]# yum-config-manager --add-repo https://openresty.org/package/centos/openresty.repo
[root@docker ~]# yum install openresty
[root@docker ~]# yum install openresty-resty

系統(tǒng)默認(rèn)安裝在/usr/local/openresty/目錄下,版本如下

[root@docker openresty]# cd /usr/local/openresty/bin/
[root@docker bin]# ./openresty -v
nginx version: openresty/1.13.6.2

可以將OpenResty目錄加到PATH里，方便使用.

修改nginx.conf文件測試是否安裝成功

tee /usr/local/openresty/nginx/conf/nginx.conf <<-"EOF"
worker_processes  1;
error_log logs/error.log;
events {
    worker_connections 1024;
}
http {
    server {
        listen 8080;
        location / {
            default_type text/html;
            content_by_lua "
                ngx.say("
hello, world
")
            ";
        }
    }
}
EOF
[root@docker conf]# openresty -s reload
[root@docker conf]# curl localhost:8080
hello, world

這里使用JWT官方推薦Lua實現(xiàn)庫,項目地址為https://github.com/SkyLothar/...,有趣的是,這個項目的介紹是這么寫的JWT For The Great Openresty,看來是為OpenResty量身定做.github上有安裝教程,但一方面有些第三方庫的安裝文檔沒有提及,另一方面有些內(nèi)容沒有用到安裝的時候可以跳過,這里將完整安裝步驟重新整理了下.

在release頁面https://github.com/SkyLothar/...下載項目源碼,截止到目前最新版為v0.1.11

下載hmac源碼,截止到目前項目還未release,只能下載項目里的源文件https://github.com/jkeys089/l...

在服務(wù)器創(chuàng)建目錄/usr/local/openresty/nginx/jwt-lua/resty,將第1步壓縮包中目錄lua-resty-jwt-0.1.11/lib/resty/下的所有l(wèi)ua文件和第2步中的hmac.lua文件拷貝到該目錄下,文件列表如下.

[root@docker resty]# pwd
/usr/local/openresty/nginx/jwt-lua/resty
[root@docker resty]# ll
total 60
-rwxr-xr-x. 1 root root 11592 Jul 18 10:40 evp.lua
-rw-r--r--. 1 root root  3796 Jul 18 10:40 hmac.lua
-rwxr-xr-x. 1 root root 27222 Jul 18 10:40 jwt.lua
-rwxr-xr-x. 1 root root 15257 Jul 18 10:40 jwt-validators.lua

修改nginx.conf驗證是否生效

tee /usr/local/openresty/nginx/conf/nginx.conf <<-"EOF"
worker_processes  1;
error_log logs/error.log info;
events {
    worker_connections 1024;
}
http {
    lua_package_path "/usr/local/openresty/nginx/jwt-lua/?.lua;;";
    server {
        listen 8080;
        default_type text/plain;
        location = / {
            content_by_lua "
                local cjson = require "cjson"
                local jwt = require "resty.jwt"

                local jwt_token = "eyJ0eXAiOiJKV1QiLCJhbGciOiJIUzI1NiJ9" ..
                    ".eyJmb28iOiJiYXIifQ" ..
                    ".VAoRL1IU0nOguxURF2ZcKR0SGKE1gCbqwyh8u2MLAyY"
                local jwt_obj = jwt:verify("lua-resty-jwt", jwt_token)
                ngx.say(cjson.encode(jwt_obj))
            ";
        }
        location = /sign {
            content_by_lua "
                local cjson = require "cjson"
                local jwt = require "resty.jwt"

                local jwt_token = jwt:sign(
                    "lua-resty-jwt",
                    {
                        header={typ="JWT", alg="HS256"},
                        payload={foo="bar"}
                    }
                )
                ngx.say(jwt_token)
            ";
        }
    }
}
EOF

[root@docker resty]# curl localhost:8080
{"signature":"VAoRL1IU0nOguxURF2ZcKR0SGKE1gCbqwyh8u2MLAyY","reason":"everything is awesome~ :p","valid":true,"raw_header":"eyJ0eXAiOiJKV1QiLCJhbGciOiJIUzI1NiJ9","payload":{"foo":"bar"},"header":{"alg":"HS256","typ":"JWT"},"verified":true,"raw_payload":"eyJmb28iOiJiYXIifQ"}

驗證通過,jwt模塊安裝完畢

上面jwt模塊還無法用于生產(chǎn)環(huán)境,有幾個問題沒解決

jwt token目前是寫死在配置文件里,生產(chǎn)需要從header Authorization中獲取

驗證失敗目前返回是200生產(chǎn)需要返回401

需要配置反向代理并且將用戶信息放在代理header上

local jwt = require "resty.jwt"
local cjson = require "cjson"
--your secret
local secret = "5pil6aOO5YaN576O5Lmf5q+U5LiN5LiK5bCP6ZuF55qE56yR"

local M = {}

function M.auth(claim_specs)
    -- require Authorization request header
    local auth_header = ngx.var.http_Authorization

    if auth_header == nil then
        ngx.log(ngx.WARN, "No Authorization header")
        ngx.exit(ngx.HTTP_UNAUTHORIZED)
    end

    ngx.log(ngx.INFO, "Authorization: " .. auth_header)

    -- require Bearer token
    local _, _, token = string.find(auth_header, "Bearer%s+(.+)")

    if token == nil then
        ngx.log(ngx.WARN, "Missing token")
        ngx.exit(ngx.HTTP_UNAUTHORIZED)
    end

    ngx.log(ngx.INFO, "Token: " .. token)

    local jwt_obj = jwt:verify(secret, token)
    if jwt_obj.verified == false then
        ngx.log(ngx.WARN, "Invalid token: ".. jwt_obj.reason)
        ngx.exit(ngx.HTTP_UNAUTHORIZED)
    end

    ngx.log(ngx.INFO, "JWT: " .. cjson.encode(jwt_obj))

    -- write the uid variable
    ngx.var.uid = jwt_obj.payload.sub
end

return M

worker_processes  1;
error_log logs/error.log info;
events {
    worker_connections 1024;
}
http {
    upstream tomcat{
     server localhost:80;
    }
    lua_package_path "/usr/local/openresty/nginx/jwt-lua/?.lua;;";
    server {
        listen 8080;
        set $uid "";
        location / {
            access_by_lua "
            local jwt = require("resty.nginx-jwt")
            jwt.auth()
        ";
            default_type application/json;
            proxy_set_header uid $uid;
            proxy_pass http://tomcat;
        }
    }
}

這里后臺啟動了一臺tomcat并設(shè)置監(jiān)聽端口為80,tomcat上部署了一個示例的war包,代碼邏輯較簡單,就是輸出所有的header,代碼如下:

package asan.demo;
import java.io.IOException;
import java.io.PrintWriter;
import java.util.Enumeration;
import javax.servlet.*;
import javax.servlet.http.*;

public class JWTDemoService extends HttpServlet {
    private static final String CONTENT_TYPE = "text/html; charset=UTF-8";

    public void init(ServletConfig config) throws ServletException {
        super.init(config);
    }

    public void service(HttpServletRequest request,
                        HttpServletResponse response) throws ServletException,
                                                             IOException {
        response.setContentType(CONTENT_TYPE);
        PrintWriter out = response.getWriter();
        Enumeration em=request.getHeaderNames();
        while(em.hasMoreElements()){
            String key=(String)em.nextElement();
            String value=(String)request.getHeaders(key).nextElement();
            out.println(String.format("%s ==> %s", key,value));
        }
        out.close();
    }
}

重啟OpenResty測試,如果沒有指定jwt token信息返回401

[root@docker conf]# curl http://localhost:8080/jwtdemo/service



401 Authorization Required
openresty/1.13.6.2

指定jwt token

[root@docker conf]# curl -i http://localhost:8080/jwtdemo/ -H "Authorization: Bearer eyJ0eXAiOiJKV1QiLCJhbGciOiJIUzI1NiJ9.eyJqdGkiOiJ5YXlhIiwiaWF0IjoxNTMxODkyNzE3LCJpc3MiOiJ5YXlhIiwic3ViIjoieWF5YSIsImV4cCI6MTUzMTkyODcxN30.W5UXlwKHSrpUAYbfoF-fTBTS9Enm1wsvCKNQm0yLSfQ"
HTTP/1.1 200
Server: openresty/1.13.6.2
Date: Wed, 18 Jul 2018 05:52:13 GMT
Content-Type: text/html;charset=UTF-8
Content-Length: 298
Connection: keep-alive

uid ==> yaya
host ==> tomcat
connection ==> close
user-agent ==> curl/7.29.0
accept ==> */*
authorization ==> Bearer eyJ0eXAiOiJKV1QiLCJhbGciOiJIUzI1NiJ9.eyJqdGkiOiJ5YXlhIiwiaWF0IjoxNTMxODkyNzE3LCJpc3MiOiJ5YXlhIiwic3ViIjoieWF5YSIsImV4cCI6MTUzMTkyODcxN30.W5UXlwKHSrpUAYbfoF-fTBTS9Enm1wsvCKNQm0yLSfQ

從結(jié)果上看,后臺服務(wù)已經(jīng)獲取到uid這個header
至于請求用到j(luò)wt token可以從任意平臺生成只要保證secret一樣即可,根據(jù)官網(wǎng)介紹,該庫目前支持到j(luò)wt生成算法如圖:

為每個請求生成唯一的uuid碼可以將網(wǎng)關(guān)層上的請求和應(yīng)用層的請求關(guān)聯(lián)起來,對排查問題,接口統(tǒng)計都非常有用.

創(chuàng)建文件/usr/local/openresty/nginx/jwt-lua/resty/uuid.lua

local M  = {}
local charset = {}  do -- [0-9a-zA-Z]
    for c = 48, 57  do table.insert(charset, string.char(c)) end
    for c = 65, 90  do table.insert(charset, string.char(c)) end
    for c = 97, 122 do table.insert(charset, string.char(c)) end
end
function M.uuid(length)
        local res = ""
        for i = 1, length do
                res = res .. charset[math.random(1, #charset)]
        end
        return res
end
return M

修改配置文件nginx.conf

worker_processes  1;
error_log logs/error.log info;
events {
    worker_connections 1024;
}
http {
    upstream tomcat{
     server localhost:80;
    }
    lua_package_path "/usr/local/openresty/nginx/jwt-lua/?.lua;;";
    server {
        listen 8080;
        set $uid "";
        set $uuid "";
        location / {
            access_by_lua "
            local jwt = require("resty.nginx-jwt")
            jwt.auth()
            local u = require("resty.uuid")
            ngx.var.uuid = u.uuid(64)
        ";
            default_type application/json;
            proxy_set_header uid $uid;
            proxy_set_header uuid $uuid;
            proxy_pass http://tomcat;
        }
    }
}

重啟OpenResty,測試

[root@docker conf]# openresty -s reload
[root@docker conf]# curl -i http://localhost:8080/jwtdemo/ -H "Authorization: Bearer eyJ0eXAiOiJKV1QiLCJhbGciOiJIUzI1NiJ9.eyJqdGkiOiJ5YXlhIiwiaWF0IjoxNTMxODk0MDA3LCJpc3MiOiJ5YXlhIiwic3ViIjoieWF5YSIsImV4cCI6MTUzMTkzMDAwN30.vQvpQpIHCmK5QBgIoRR8jhIGeYlHOMYySIr4gHvoZFE"
HTTP/1.1 200
Server: openresty/1.13.6.2
Date: Wed, 18 Jul 2018 08:05:45 GMT
Content-Type: text/html;charset=UTF-8
Content-Length: 372
Connection: keep-alive

uid ==> yaya
uuid ==> nhak5eLjQZ73yhAyHLTgZnSBeDa8pa1p3pcpBFvJ4Mv1fkY782UgVr8Islheq03l
host ==> tomcat
connection ==> close
user-agent ==> curl/7.29.0
accept ==> */*
authorization ==> Bearer eyJ0eXAiOiJKV1QiLCJhbGciOiJIUzI1NiJ9.eyJqdGkiOiJ5YXlhIiwiaWF0IjoxNTMxODk0MDA3LCJpc3MiOiJ5YXlhIiwic3ViIjoieWF5YSIsImV4cCI6MTUzMTkzMDAwN30.vQvpQpIHCmK5QBgIoRR8jhIGeYlHOMYySIr4gHvoZFE

可以看到,多了一個uuid的請求頭

這里提供一個生成jwt token的java示例

package com.yaya;

import io.jsonwebtoken.JwtBuilder;
import io.jsonwebtoken.Jwts;
import io.jsonwebtoken.SignatureAlgorithm;
import javax.crypto.spec.SecretKeySpec;
import java.security.Key;
import java.util.Date;
import java.util.HashMap;
import java.util.Map;

/**
 * @Description:
 * @author: jianfeng.zheng
 * @since: 2018/7/5 下午9:56
 * @history: 1.2018/7/5 created by jianfeng.zheng
 */
public class JWTDemo {
    
    public static final String SECRET="5pil6aOO5YaN576O5Lmf5q+U5LiN5LiK5bCP6ZuF55qE56yR";
    
    public static String createJWT(String uid, long ttlMillis) throws Exception {
        SignatureAlgorithm signatureAlgorithm = SignatureAlgorithm.HS256;
        long nowMillis = System.currentTimeMillis();
        Date now = new Date(nowMillis);
        Key signingKey = new SecretKeySpec(SECRET.getBytes(), signatureAlgorithm.getJcaName());

        Map header=new HashMap();
        header.put("typ","JWT");
        header.put("alg","HS256");
        JwtBuilder builder = Jwts.builder().setId(uid)
                .setIssuedAt(now)
                .setIssuer(uid)
                .setSubject(uid)
                .setHeader(header)
                .signWith(signatureAlgorithm, signingKey);
        if (ttlMillis >= 0) {
            long expMillis = nowMillis + ttlMillis;
            Date exp = new Date(expMillis);
            builder.setExpiration(exp);
        }
        return builder.compact();
    }

    public static void main(String[]cmd) throws Exception {
        String s=createJWT("yaya",36000000);
        System.out.println("Bearer "+s);
    }

}

pom.xml

    4.0.0

    com.yaya
    jwtdemo
    1.0-SNAPSHOT
    
        
            io.jsonwebtoken
            jjwt
            0.6.0
        
    

這里只是解決了文章開頭提到的第一個問題,接口需要知道是誰調(diào)用了接口,第二個問題,用戶能不能調(diào)接口目前考慮用aop在應(yīng)用層實現(xiàn),后續(xù)也會繼續(xù)更新.