在開始本教學之前,請保證已經熟悉以下幾點。
Controller
、 RestController
、 Autowired
等這些基本註釋。其實看看官方的 Getting-Start 教學就差不多了。簡要的說明下我們為什麼要用 JWT ,因為我們要實現完全的前後端分離,所以不可能使用 session
, cookie
的方式進行鑑權,所以 JWT 就被派上了用場,你可以通過一個加密金鑰來進行前後端的鑑權。
/login
進行登入,如果成功返回一個加密 token,失敗的話直接返回 401 錯誤。header
中新增 Authorization
欄位,例如 Authorization: token
,token
為金鑰。token
的校驗,如果有誤會直接返回 401。username
資訊在 token 中。token
進行加密。token
中攜帶的 username
資訊。token
是否正確。新建一個 Maven 工程,新增相關的 dependencies。
<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
<modelVersion>4.0.0</modelVersion>
<groupId>org.inlighting</groupId>
<artifactId>shiro-study</artifactId>
<version>1.0-SNAPSHOT</version>
<dependencies>
<dependency>
<groupId>org.apache.shiro</groupId>
<artifactId>shiro-spring</artifactId>
<version>1.3.2</version>
</dependency>
<dependency>
<groupId>com.auth0</groupId>
<artifactId>java-jwt</artifactId>
<version>3.2.0</version>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-web</artifactId>
<version>1.5.8.RELEASE</version>
</dependency>
</dependencies>
<build>
<plugins>
<!-- Srping Boot 打包工具 -->
<plugin>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-maven-plugin</artifactId>
<version>1.5.7.RELEASE</version>
<executions>
<execution>
<goals>
<goal>repackage</goal>
</goals>
</execution>
</executions>
</plugin>
<!-- 指定JDK編譯版本 -->
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-compiler-plugin</artifactId>
<configuration>
<source>1.8</source>
<target>1.8</target>
<encoding>UTF-8</encoding>
</configuration>
</plugin>
</plugins>
</build>
</project>
注意指定JDK版本和編碼。
為了縮減教學的程式碼,我使用 HashMap
本地模擬了一個資料庫,結構如下:
username | password | role | permission |
---|---|---|---|
smith | smith123 | user | view |
danny | danny123 | admin | view,edit |
這是一個最簡單的使用者許可權表,如果想更加進一步瞭解,自行百度 RBAC。
之後再構建一個 UserService
來模擬資料庫查詢,並且把結果放到 UserBean
之中。
UserService.java
@Component
public class UserService {
public UserBean getUser(String username) {
// 沒有此使用者直接返回null
if (! DataSource.getData().containsKey(username))
return null;
UserBean user = new UserBean();
Map<String, String> detail = DataSource.getData().get(username);
user.setUsername(username);
user.setPassword(detail.get("password"));
user.setRole(detail.get("role"));
user.setPermission(detail.get("permission"));
return user;
}
}
UserBean.java
public class UserBean {
private String username;
private String password;
private String role;
private String permission;
public String getUsername() {
return username;
}
public void setUsername(String username) {
this.username = username;
}
public String getPassword() {
return password;
}
public void setPassword(String password) {
this.password = password;
}
public String getRole() {
return role;
}
public void setRole(String role) {
this.role = role;
}
public String getPermission() {
return permission;
}
public void setPermission(String permission) {
this.permission = permission;
}
}
我們寫一個簡單的 JWT 加密,校驗工具,並且使用使用者自己的密碼充當加密金鑰,這樣保證了 token 即使被他人截獲也無法破解。並且我們在 token
中附帶了 username
資訊,並且設定金鑰5分鐘就會過期。
public class JWTUtil {
// 過期時間5分鐘
private static final long EXPIRE_TIME = 5*60*1000;
/**
* 校驗token是否正確
* @param token 金鑰
* @param secret 使用者的密碼
* @return 是否正確
*/
public static boolean verify(String token, String username, String secret) {
try {
Algorithm algorithm = Algorithm.HMAC256(secret);
JWTVerifier verifier = JWT.require(algorithm)
.withClaim("username", username)
.build();
DecodedJWT jwt = verifier.verify(token);
return true;
} catch (Exception exception) {
return false;
}
}
/**
* 獲得token中的資訊無需secret解密也能獲得
* @return token中包含的使用者名稱
*/
public static String getUsername(String token) {
try {
DecodedJWT jwt = JWT.decode(token);
return jwt.getClaim("username").asString();
} catch (JWTDecodeException e) {
return null;
}
}
/**
* 生成簽名,5min後過期
* @param username 使用者名稱
* @param secret 使用者的密碼
* @return 加密的token
*/
public static String sign(String username, String secret) {
try {
Date date = new Date(System.currentTimeMillis()+EXPIRE_TIME);
Algorithm algorithm = Algorithm.HMAC256(secret);
// 附帶username資訊
return JWT.create()
.withClaim("username", username)
.withExpiresAt(date)
.sign(algorithm);
} catch (UnsupportedEncodingException e) {
return null;
}
}
}
ResponseBean.java
既然想要實現 restful,那我們要保證每次返回的格式都是相同的,因此我建立了一個 ResponseBean
來統一返回的格式。
public class ResponseBean {
// http 狀態碼
private int code;
// 返回資訊
private String msg;
// 返回的資料
private Object data;
public ResponseBean(int code, String msg, Object data) {
this.code = code;
this.msg = msg;
this.data = data;
}
public int getCode() {
return code;
}
public void setCode(int code) {
this.code = code;
}
public String getMsg() {
return msg;
}
public void setMsg(String msg) {
this.msg = msg;
}
public Object getData() {
return data;
}
public void setData(Object data) {
this.data = data;
}
}
自定義異常
為了實現我自己能夠手動丟擲異常,我自己寫了一個 UnauthorizedException.java
public class UnauthorizedException extends RuntimeException {
public UnauthorizedException(String msg) {
super(msg);
}
public UnauthorizedException() {
super();
}
}
URL結構
URL | 作用 |
---|---|
/login | 登入 |
/article | 所有人都可以存取,但是使用者與遊客看到的內容不同 |
/require_auth | 登入的使用者才可以進行存取 |
/require_role | admin的角色使用者才可以登入 |
/require_permission | 擁有view和edit許可權的使用者才可以存取 |
Controller
@RestController
public class WebController {
private static final Logger LOGGER = LogManager.getLogger(WebController.class);
private UserService userService;
@Autowired
public void setService(UserService userService) {
this.userService = userService;
}
@PostMapping("/login")
public ResponseBean login(@RequestParam("username") String username,
@RequestParam("password") String password) {
UserBean userBean = userService.getUser(username);
if (userBean.getPassword().equals(password)) {
return new ResponseBean(200, "Login success", JWTUtil.sign(username, password));
} else {
throw new UnauthorizedException();
}
}
@GetMapping("/article")
public ResponseBean article() {
Subject subject = SecurityUtils.getSubject();
if (subject.isAuthenticated()) {
return new ResponseBean(200, "You are already logged in", null);
} else {
return new ResponseBean(200, "You are guest", null);
}
}
@GetMapping("/require_auth")
@RequiresAuthentication
public ResponseBean requireAuth() {
return new ResponseBean(200, "You are authenticated", null);
}
@GetMapping("/require_role")
@RequiresRoles("admin")
public ResponseBean requireRole() {
return new ResponseBean(200, "You are visiting require_role", null);
}
@GetMapping("/require_permission")
@RequiresPermissions(logical = Logical.AND, value = {"view", "edit"})
public ResponseBean requirePermission() {
return new ResponseBean(200, "You are visiting permission require edit,view", null);
}
@RequestMapping(path = "/401")
@ResponseStatus(HttpStatus.UNAUTHORIZED)
public ResponseBean unauthorized() {
return new ResponseBean(401, "Unauthorized", null);
}
}
處理框架異常
之前說過 restful 要統一返回的格式,所以我們也要全域性處理 Spring Boot
的丟擲異常。利用 @RestControllerAdvice
能很好的實現。
@RestControllerAdvice
public class ExceptionController {
// 捕捉shiro的異常
@ResponseStatus(HttpStatus.UNAUTHORIZED)
@ExceptionHandler(ShiroException.class)
public ResponseBean handle401(ShiroException e) {
return new ResponseBean(401, e.getMessage(), null);
}
// 捕捉UnauthorizedException
@ResponseStatus(HttpStatus.UNAUTHORIZED)
@ExceptionHandler(UnauthorizedException.class)
public ResponseBean handle401() {
return new ResponseBean(401, "Unauthorized", null);
}
// 捕捉其他所有異常
@ExceptionHandler(Exception.class)
@ResponseStatus(HttpStatus.BAD_REQUEST)
public ResponseBean globalException(HttpServletRequest request, Throwable ex) {
return new ResponseBean(getStatus(request).value(), ex.getMessage(), null);
}
private HttpStatus getStatus(HttpServletRequest request) {
Integer statusCode = (Integer) request.getAttribute("javax.servlet.error.status_code");
if (statusCode == null) {
return HttpStatus.INTERNAL_SERVER_ERROR;
}
return HttpStatus.valueOf(statusCode);
}
}
大家可以先看下官方的 Spring-Shiro 整合教學,有個初步的瞭解。不過既然我們用了 Spring-Boot
,那我們肯定要爭取零組態檔。
實現JWTToken
JWTToken
差不多就是 Shiro
使用者名稱密碼的載體。因為我們是前後端分離,伺服器無需儲存使用者狀態,所以不需要 RememberMe
這類功能,我們簡單的實現下 AuthenticationToken
介面即可。因為 token
自己已經包含了使用者名稱等資訊,所以這裡我就弄了一個欄位。如果你喜歡鑽研,可以看看官方的 UsernamePasswordToken
是如何實現的。
public class JWTToken implements AuthenticationToken {
// 金鑰
private String token;
public JWTToken(String token) {
this.token = token;
}
@Override
public Object getPrincipal() {
return token;
}
@Override
public Object getCredentials() {
return token;
}
}
實現Realm
realm
的用於處理使用者是否合法的這一塊,需要我們自己實現。
@Service
public class MyRealm extends AuthorizingRealm {
private static final Logger LOGGER = LogManager.getLogger(MyRealm.class);
private UserService userService;
@Autowired
public void setUserService(UserService userService) {
this.userService = userService;
}
/**
* 大坑!,必須重寫此方法,不然Shiro會報錯
*/
@Override
public boolean supports(AuthenticationToken token) {
return token instanceof JWTToken;
}
/**
* 只有當需要檢測使用者許可權的時候才會呼叫此方法,例如checkRole,checkPermission之類的
*/
@Override
protected AuthorizationInfo doGetAuthorizationInfo(PrincipalCollection principals) {
String username = JWTUtil.getUsername(principals.toString());
UserBean user = userService.getUser(username);
SimpleAuthorizationInfo simpleAuthorizationInfo = new SimpleAuthorizationInfo();
simpleAuthorizationInfo.addRole(user.getRole());
Set<String> permission = new HashSet<>(Arrays.asList(user.getPermission().split(",")));
simpleAuthorizationInfo.addStringPermissions(permission);
return simpleAuthorizationInfo;
}
/**
* 預設使用此方法進行使用者名稱正確與否驗證,錯誤丟擲異常即可。
*/
@Override
protected AuthenticationInfo doGetAuthenticationInfo(AuthenticationToken auth) throws AuthenticationException {
String token = (String) auth.getCredentials();
// 解密獲得username,用於和資料庫進行對比
String username = JWTUtil.getUsername(token);
if (username == null) {
throw new AuthenticationException("token invalid");
}
UserBean userBean = userService.getUser(username);
if (userBean == null) {
throw new AuthenticationException("User didn't existed!");
}
if (! JWTUtil.verify(token, username, userBean.getPassword())) {
throw new AuthenticationException("Username or password error");
}
return new SimpleAuthenticationInfo(token, token, "my_realm");
}
}
在 doGetAuthenticationInfo()
中使用者可以自定義丟擲很多異常,詳情見檔案。
重寫 Filter
所有的請求都會先經過 Filter
,所以我們繼承官方的 BasicHttpAuthenticationFilter
,並且重寫鑑權的方法。
程式碼的執行流程 preHandle
-> isAccessAllowed
-> isLoginAttempt
-> executeLogin
。
public class JWTFilter extends BasicHttpAuthenticationFilter {
private Logger LOGGER = LoggerFactory.getLogger(this.getClass());
/**
* 判斷使用者是否想要登入。
* 檢測header裡面是否包含Authorization欄位即可
*/
@Override
protected boolean isLoginAttempt(ServletRequest request, ServletResponse response) {
HttpServletRequest req = (HttpServletRequest) request;
String authorization = req.getHeader("Authorization");
return authorization != null;
}
/**
*
*/
@Override
protected boolean executeLogin(ServletRequest request, ServletResponse response) throws Exception {
HttpServletRequest httpServletRequest = (HttpServletRequest) request;
String authorization = httpServletRequest.getHeader("Authorization");
JWTToken token = new JWTToken(authorization);
// 提交給realm進行登入,如果錯誤他會丟擲異常並被捕獲
getSubject(request, response).login(token);
// 如果沒有丟擲異常則代表登入成功,返回true
return true;
}
/**
* 這裡我們詳細說明下為什麼最終返回的都是true,即允許存取
* 例如我們提供一個地址 GET /article
* 登入使用者和遊客看到的內容是不同的
* 如果在這裡返回了false,請求會被直接攔截,使用者看不到任何東西
* 所以我們在這裡返回true,Controller中可以通過 subject.isAuthenticated() 來判斷使用者是否登入
* 如果有些資源只有登入使用者才能存取,我們只需要在方法上面加上 @RequiresAuthentication 註解即可
* 但是這樣做有一個缺點,就是不能夠對GET,POST等請求進行分別過濾鑑權(因為我們重寫了官方的方法),但實際上對應用影響不大
*/
@Override
protected boolean isAccessAllowed(ServletRequest request, ServletResponse response, Object mappedValue) {
if (isLoginAttempt(request, response)) {
try {
executeLogin(request, response);
} catch (Exception e) {
response401(request, response);
}
}
return true;
}
/**
* 對跨域提供支援
*/
@Override
protected boolean preHandle(ServletRequest request, ServletResponse response) throws Exception {
HttpServletRequest httpServletRequest = (HttpServletRequest) request;
HttpServletResponse httpServletResponse = (HttpServletResponse) response;
httpServletResponse.setHeader("Access-control-Allow-Origin", httpServletRequest.getHeader("Origin"));
httpServletResponse.setHeader("Access-Control-Allow-Methods", "GET,POST,OPTIONS,PUT,DELETE");
httpServletResponse.setHeader("Access-Control-Allow-Headers", httpServletRequest.getHeader("Access-Control-Request-Headers"));
// 跨域時會首先傳送一個option請求,這裡我們給option請求直接返回正常狀態
if (httpServletRequest.getMethod().equals(RequestMethod.OPTIONS.name())) {
httpServletResponse.setStatus(HttpStatus.OK.value());
return false;
}
return super.preHandle(request, response);
}
/**
* 將非法請求跳轉到 /401
*/
private void response401(ServletRequest req, ServletResponse resp) {
try {
HttpServletResponse httpServletResponse = (HttpServletResponse) resp;
httpServletResponse.sendRedirect("/401");
} catch (IOException e) {
LOGGER.error(e.getMessage());
}
}
}
getSubject(request, response).login(token);
這一步就是提交給了 realm
進行處理。
設定Shiro
@Configuration
public class ShiroConfig {
@Bean("securityManager")
public DefaultWebSecurityManager getManager(MyRealm realm) {
DefaultWebSecurityManager manager = new DefaultWebSecurityManager();
// 使用自己的realm
manager.setRealm(realm);
/*
* 關閉shiro自帶的session,詳情見檔案
* http://shiro.apache.org/session-management.html#SessionManagement-StatelessApplications%28Sessionless%29
*/
DefaultSubjectDAO subjectDAO = new DefaultSubjectDAO();
DefaultSessionStorageEvaluator defaultSessionStorageEvaluator = new DefaultSessionStorageEvaluator();
defaultSessionStorageEvaluator.setSessionStorageEnabled(false);
subjectDAO.setSessionStorageEvaluator(defaultSessionStorageEvaluator);
manager.setSubjectDAO(subjectDAO);
return manager;
}
@Bean("shiroFilter")
public ShiroFilterFactoryBean factory(DefaultWebSecurityManager securityManager) {
ShiroFilterFactoryBean factoryBean = new ShiroFilterFactoryBean();
// 新增自己的過濾器並且取名為jwt
Map<String, Filter> filterMap = new HashMap<>();
filterMap.put("jwt", new JWTFilter());
factoryBean.setFilters(filterMap);
factoryBean.setSecurityManager(securityManager);
factoryBean.setUnauthorizedUrl("/401");
/*
* 自定義url規則
* http://shiro.apache.org/web.html#urls-
*/
Map<String, String> filterRuleMap = new HashMap<>();
// 所有請求通過我們自己的JWT Filter
filterRuleMap.put("/**", "jwt");
// 存取401和404頁面不通過我們的Filter
filterRuleMap.put("/401", "anon");
factoryBean.setFilterChainDefinitionMap(filterRuleMap);
return factoryBean;
}
/**
* 下面的程式碼是新增註解支援
*/
@Bean
@DependsOn("lifecycleBeanPostProcessor")
public DefaultAdvisorAutoProxyCreator defaultAdvisorAutoProxyCreator() {
DefaultAdvisorAutoProxyCreator defaultAdvisorAutoProxyCreator = new DefaultAdvisorAutoProxyCreator();
// 強制使用cglib,防止重複代理和可能引起代理出錯的問題
// https://zhuanlan.zhihu.com/p/29161098
defaultAdvisorAutoProxyCreator.setProxyTargetClass(true);
return defaultAdvisorAutoProxyCreator;
}
@Bean
public LifecycleBeanPostProcessor lifecycleBeanPostProcessor() {
return new LifecycleBeanPostProcessor();
}
@Bean
public AuthorizationAttributeSourceAdvisor authorizationAttributeSourceAdvisor(DefaultWebSecurityManager securityManager) {
AuthorizationAttributeSourceAdvisor advisor = new AuthorizationAttributeSourceAdvisor();
advisor.setSecurityManager(securityManager);
return advisor;
}
}
裡面 URL 規則自己參考檔案即可 http://shiro.apache.org/web.html 。
我就說下程式碼還有哪些可以進步的地方吧
Cache
功能。/401
地址實現。github地址及其來源:https://github.com/Smith-Crui...