实现思路：
- 客户端每次在调用接口的时候,需要在请求头中，传递令牌参数，每次令牌只能用一次，有超时时间限定。
- 一旦使用之后，就会被删除，这样可以有效防止重复提交。
本文目录结构： l____1.BaseRedisService封装Redis l____2. RedisTokenUtils工具类 l____3.自定义Api幂等注解和切面 l____4.幂等注解使用 l____5.封装生成token注解 l____6.改造ExtApiAopIdempotent l____7.API接口保证幂等性 l____8. 页面防止重复提交
下面直接上代码
1.BaseRedisService封装Redis@Component
public class BaseRedisService {
@Autowired
private StringRedisTemplate stringRedisTemplate;
public void setString(String key, Object data, Long timeout) {
if (data instanceof String) {
String value = (String) data;
stringRedisTemplate.opsForValue().set(key, value);
}
if (timeout != null) {
stringRedisTemplate.expire(key, timeout, TimeUnit.SECONDS);
}
}
public Object getString(String key) {
return stringRedisTemplate.opsForValue().get(key);
}
public void delKey(String key) {
stringRedisTemplate.delete(key);
}
}
@Component
public class RedisTokenUtils {
private long timeout = 60 * 60;
@Autowired
private BaseRedisService baseRedisService;
// 将token存入在redis
public String getToken() {
String token = "token" + System.currentTimeMillis();
baseRedisService.setString(token, token, timeout);
return token;
}
public boolean findToken(String tokenKey) {
String token = (String) baseRedisService.getString(tokenKey);
if (StringUtils.isEmpty(token)) {
return false;
}
// token 获取成功后 删除对应tokenMapstoken
baseRedisService.delKey(token);
return true;
}
}
1. 注解:
@Target(value = ElementType.METHOD)
@Retention(RetentionPolicy.RUNTIME)
public @interface ExtApiIdempotent {
String value();
}
2. 切面：
@Aspect
@Component
public class ExtApiAopIdempotent {
@Autowired
private RedisTokenUtils redisTokenUtils;
@Pointcut("execution(public * com.itmayiedu.controller.*.*(..))")
public void rlAop() {
}
@Around("rlAop()")
public Object doBefore(ProceedingJoinPoint proceedingJoinPoint) throws Throwable {
MethodSignature signature = (MethodSignature) proceedingJoinPoint.getSignature();
ExtApiIdempotent extApiIdempotent = signature.getMethod().getDeclaredAnnotation(ExtApiIdempotent.class);
if (extApiIdempotent == null) {
// 直接执行程序
Object proceed = proceedingJoinPoint.proceed();
return proceed;
}
// 代码步骤：
// 1.获取令牌 存放在请求头中
HttpServletRequest request = getRequest();
String token = request.getHeader("token");
if (StringUtils.isEmpty(token)) {
response("参数错误!");
return null;
}
// 2.判断令牌是否在缓存中有对应的令牌
// 3.如何缓存没有该令牌的话，直接报错（请勿重复提交）
// 4.如何缓存有该令牌的话，直接执行该业务逻辑
// 5.执行完业务逻辑之后，直接删除该令牌。
if (!redisTokenUtils.findToken(token)) {
response("请勿重复提交!");
return null;
}
Object proceed = proceedingJoinPoint.proceed();
return proceed;
}
public HttpServletRequest getRequest() {
ServletRequestAttributes attributes = (ServletRequestAttributes) RequestContextHolder.getRequestAttributes();
HttpServletRequest request = attributes.getRequest();
return request;
}
public void response(String msg) throws IOException {
ServletRequestAttributes attributes = (ServletRequestAttributes) RequestContextHolder.getRequestAttributes();
HttpServletResponse response = attributes.getResponse();
response.setHeader("Content-type", "text/html;charset=UTF-8");
PrintWriter writer = response.getWriter();
try {
writer.println(msg);
} catch (Exception e) {
} finally {
writer.close();
}
}
}
// 从redis中获取Token
@RequestMapping("/redisToken")
public String RedisToken() {
return redisTokenUtils.getToken();
}
// 验证Token
@RequestMapping(value = "/addOrderExtApiIdempotent", produces = "application/json; charset=utf-8")
@ExtApiIdempotent
public String addOrderExtApiIdempotent(@RequestBody OrderEntity orderEntity, HttpServletRequest request) {
int result = orderMapper.addOrder(orderEntity);
return result > 0 ? "添加成功" : "添加失败" + "";
}
@Target(value = ElementType.METHOD)
@Retention(RetentionPolicy.RUNTIME)
public @interface ExtApiToken {
}
@Aspect
@Component
public class ExtApiAopIdempotent {
@Autowired
private RedisTokenUtils redisTokenUtils;
@Pointcut("execution(public * com.itmayiedu.controller.*.*(..))")
public void rlAop() {
}
// 前置通知转发Token参数
@Before("rlAop()")
public void before(JoinPoint point) {
MethodSignature signature = (MethodSignature) point.getSignature();
ExtApiToken extApiToken = signature.getMethod().getDeclaredAnnotation(ExtApiToken.class);
if (extApiToken != null) {
extApiToken();
}
}
// 环绕通知验证参数
@Around("rlAop()")
public Object doAround(ProceedingJoinPoint proceedingJoinPoint) throws Throwable {
MethodSignature signature = (MethodSignature) proceedingJoinPoint.getSignature();
ExtApiIdempotent extApiIdempotent = signature.getMethod().getDeclaredAnnotation(ExtApiIdempotent.class);
if (extApiIdempotent != null) {
return extApiIdempotent(proceedingJoinPoint, signature);
}
// 放行
Object proceed = proceedingJoinPoint.proceed();
return proceed;
}
// 验证Token
public Object extApiIdempotent(ProceedingJoinPoint proceedingJoinPoint, MethodSignature signature)
throws Throwable {
ExtApiIdempotent extApiIdempotent = signature.getMethod().getDeclaredAnnotation(ExtApiIdempotent.class);
if (extApiIdempotent == null) {
// 直接执行程序
Object proceed = proceedingJoinPoint.proceed();
return proceed;
}
// 代码步骤：
// 1.获取令牌 存放在请求头中
HttpServletRequest request = getRequest();
String valueType = extApiIdempotent.value();
if (StringUtils.isEmpty(valueType)) {
response("参数错误!");
return null;
}
String token = null;
if (valueType.equals(ConstantUtils.EXTAPIHEAD)) {
token = request.getHeader("token");
} else {
token = request.getParameter("token");
}
if (StringUtils.isEmpty(token)) {
response("参数错误!");
return null;
}
if (!redisTokenUtils.findToken(token)) {
response("请勿重复提交!");
return null;
}
Object proceed = proceedingJoinPoint.proceed();
return proceed;
}
public void extApiToken() {
String token = redisTokenUtils.getToken();
getRequest().setAttribute("token", token);
}
public HttpServletRequest getRequest() {
ServletRequestAttributes attributes = (ServletRequestAttributes) RequestContextHolder.getRequestAttributes();
HttpServletRequest request = attributes.getRequest();
return request;
}
public void response(String msg) throws IOException {
ServletRequestAttributes attributes = (ServletRequestAttributes) RequestContextHolder.getRequestAttributes();
HttpServletResponse response = attributes.getResponse();
response.setHeader("Content-type", "text/html;charset=UTF-8");
PrintWriter writer = response.getWriter();
try {
writer.println(msg);
} catch (Exception e) {
} finally {
writer.close();
}
}
}
@RestController
public class OrderController {
@Autowired
private OrderMapper orderMapper;
@Autowired
private RedisTokenUtils redisTokenUtils;
// 从redis中获取Token
@RequestMapping("/redisToken")
public String RedisToken() {
return redisTokenUtils.getToken();
}
// 验证Token
@RequestMapping(value = "/addOrderExtApiIdempotent", produces = "application/json; charset=utf-8")
@ExtApiIdempotent(value = ConstantUtils.EXTAPIHEAD)
public String addOrderExtApiIdempotent(@RequestBody OrderEntity orderEntity, HttpServletRequest request) {
int result = orderMapper.addOrder(orderEntity);
return result > 0 ? "添加成功" : "添加失败" + "";
}
}
@Controller
public class OrderPageController {
@Autowired
private OrderMapper orderMapper;
@RequestMapping("/indexPage")
@ExtApiToken
public String indexPage(HttpServletRequest req) {
return "indexPage";
}
@RequestMapping("/addOrderPage")
@ExtApiIdempotent(value = ConstantUtils.EXTAPIFROM)
public String addOrder(OrderEntity orderEntity) {
int addOrder = orderMapper.addOrder(orderEntity);
return addOrder > 0 ? "success" : "fail";
}
}
