一、具體操作

二、幾點補充

1、引入Jwt依賴

<!-- https://mvnrepository.com/artifact/io.jsonwebtoken/jjwt -->
		<dependency>
			<groupId>io.jsonwebtoken</groupId>
			<artifactId>jjwt</artifactId>
			<version>0.7.0</version>
		</dependency>

2、在filter中驗證token時，過期和非法的token都會丟擲異常，可以自定義bean繼承自BasicErrorController來進行統一的異常處理（返回給前端固定的Json內容，實際使用時和Js互動還會遇到跨域問題，要給response加上相關的請求頭）。

3、貼波自己寫的程式碼

注：基於 boot 1.X， 2.X的BasicErrorController有所不同

不懂的留言

@Configuration
public class JwtConfig {

    @Bean
    public FilterRegistrationBean jwtFilter() {
        final FilterRegistrationBean registrationBean = new FilterRegistrationBean();
        registrationBean.setFilter(new JwtFilter());
        registrationBean.addUrlPatterns("/test/*");//配置對應路徑的介面使用此 filter
        return registrationBean;
    }
}
 

@RestController
public class MyCommonErrorController extends BasicErrorController {
    //統一處理filter丟擲的token相關的異常 返回給前端標準格式的json和裝填碼
    private static final String PATH = "/error";
    private static final String TOKEN_MISS = "Missing or invalid Authorization header";
    private static final String TOKEN_EXPIRED = "token expired";
    private static final String TOKEN_INVALID = "token invalid";
    private static final String TOKEN_ERROR = "error";

    public MyCommonErrorController() {
        super(new DefaultErrorAttributes(), new ErrorProperties());
    }

    @Override
    @RequestMapping(
            produces = {"application/json"}
    )
    public ResponseEntity<Map<String, Object>> error(HttpServletRequest request) {
        //加入跨域相關內容
        HttpServletResponse response = ((ServletRequestAttributes) RequestContextHolder.getRequestAttributes()).getResponse();
        response.setHeader("Access-Control-Allow-Origin", "*");
        response.setHeader("Access-Control-Expose-Headers", "X-Total-Count");
        response.setHeader("Access-Control-Allow-Headers", "origin, x-requested-with, x-http-method-override, content-type, Authentication, Authorization, hospital");
        response.setHeader("Access-Control-Allow-Methods", "PUT, GET, POST, DELETE, OPTIONS, HEAD, PATCH");
        
        HttpStatus status = this.getStatus(request);
        Map<String, Object> errorAttributes = this.getErrorAttributes(request, true);
        String message = (String)errorAttributes.get("message");
        Map<String, Object> body = new LinkedHashMap<>(16);
        body.put("code", getCode(message));
        body.put("message", message);
        body.put("data", null);
        return new ResponseEntity(body, status);
    }

    private int getCode(String msg){
        if (TOKEN_MISS.equals(msg)){
            return -1;
        }else if (TOKEN_EXPIRED.equals(msg)){
            return -2;
        }else if (TOKEN_INVALID.equals(msg)){
            return -3;
        }else if (TOKEN_ERROR.equals(msg)){
            return -4;
        }else {
            return -5;
        }
    }

    @Override
    public String getErrorPath() {
        return PATH;
    }
}
 

@RestController
public class TokenController {
    //登陸介面
    @PostMapping("/login")
    public Object login(@RequestBody LoginRequest loginRequest){
        //假設驗證過了使用者名稱和密碼 發token
        // Create Twt token
        return generateToken(loginRequest.getUsername());
    }

    private String generateToken(String username) {
        Map<String, Object> claims = new HashMap<>(16);
        claims.put("sub", username);
        claims.put("created", new Date());
        return generateToken((claims));
    }
    
    private String generateToken(Map<String, Object> claims) {
        return Jwts.builder().setClaims(claims)        //payload
                .setExpiration(new Date(System.currentTimeMillis() + 60 * 1000L))  //過期時間
                .signWith(SignatureAlgorithm.HS512, "nicai").compact();  //加密方式
    }
}

@RestController
@RequestMapping("/test")
public class TestController {
    //用於測試token的驗證
    @GetMapping("")
    public Object getTest(HttpServletRequest request){
        System.out.println(request.getAttribute("claims"));
        Map<String, String> claims = (Map<String, String>) request.getAttribute("claims");
        return "test"; 
    }
}

@Data
public class TokenException extends Exception {
    //自定義異常型別
    private int code;
    private String msg;

    public TokenException() {
    }

    public TokenException(int code, String msg) {
        super(msg);
        this.code = code;
        this.msg = msg;
    }
}

public class JwtFilter extends GenericFilterBean{
    //Jwtconfig中配置的filter 用於Jwt token的驗證工作 配置時可以指定對應的路徑
    @Override
    public void doFilter(ServletRequest servletRequest, ServletResponse servletResponse, FilterChain filterChain) throws IOException, ServletException {
        final HttpServletResponse response = (HttpServletResponse) servletResponse;
        final HttpServletRequest request = (HttpServletRequest) servletRequest;
        String authHeader = request.getHeader("Authorization");

        //規避探測性質的 OPTIONS請求
        String optionsString = "OPTIONS";
        String bearerString = "Bearer ";
        if (optionsString.equals(request.getMethod())){
            response.setStatus(HttpServletResponse.SC_OK);
            filterChain.doFilter(servletRequest, servletResponse);
        }else {
            //驗證token
            if (StringUtils.isEmpty(authHeader) || !authHeader.startsWith(bearerString)){
                    throw new ServletException(new TokenException(-1, "Missing or invalid Authorization header"));
            }else {
                String token = authHeader.substring(bearerString.length());
                try {
                    //使用jwt paser來驗證簽名
                    Claims claims = Jwts.parser().setSigningKey("nicai").parseClaimsJws(token).getBody();
                    request.setAttribute("claims", claims);
                }catch (ExpiredJwtException e){
                    throw new ServletException(new TokenException(-2, "token expired"));
                }catch (SignatureException e){
                    throw new ServletException(new TokenException(-3, "token invalid"));
                }catch (Exception e){
                    throw new ServletException(new TokenException(-4, "error"));
                }

            }
            filterChain.doFilter(servletRequest, servletResponse);
        }

    }

}