（4）服务消费者，面向前端或者用户的服务

本模块涉及到很多知识点：比如Swagger的应用，SpringCloud断路器的使用，服务API的检查、token的校验，feign消费者的使用。大致代码框架如下：

先看下简单的配置文件application.properties

spring.application.name=mallservice-app
server.port=4444
eureka.client.serviceUrl.defaultZone=http://server1:1111/eureka/,http://server2:1112/eureka/,http://server3:1113/eureka/
hystrix.command.default.execution.isolation.thread.timeoutInMilliseconds:5000
urifilter.properties

#urllist
url.filterList[0]=/acc/signup
url.filterList[1]=/acc/login
面向用户的Controller类：

package com.mallapp.api;

import com.common.constant.RestApiResult;
import com.common.constant.ReturnCode;
import com.google.gson.Gson;
import com.mallapp.Security.JWTUtils;
import com.mallapp.client.IAccountFeignClient;
import io.swagger.annotations.Api;
import io.swagger.annotations.ApiOperation;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestMethod;
import org.springframework.web.bind.annotation.RequestParam;
import org.springframework.web.bind.annotation.RestController;

import java.util.UUID;

@Api(value="用户服务",tags = "用户服务接口")
@RestController
@RequestMapping("/acc")
public class IAccountController {
@Autowired
IAccountFeignClient accountFeignClient;

@ApiOperation(value="用户注册")
@RequestMapping(value="signup",method = RequestMethod.POST)
public RestApiResult signUp(@RequestParam String phone, @RequestParam String password){
RestApiResult restApiResult = new Gson().fromJson(accountFeignClient.signUp(phone,password),RestApiResult.class);
System.out.println(restApiResult);
return restApiResult;
}
@ApiOperation(value="用户登录")
@RequestMapping(value="login",method = RequestMethod.POST)
public RestApiResult login(@RequestParam String phone ,@RequestParam String password){
RestApiResult restApiResult = new Gson().fromJson(accountFeignClient.login(phone,password),RestApiResult.class);
try{
System.out.println(restApiResult);
if (restApiResult.isSuccess()){
String accessToken = JWTUtils.createJWT(UUID.randomUUID().toString(),(String)restApiResult.getAddmessage(),2*60*60*1000);
restApiResult.setAddmessage(accessToken);
}
}catch (Exception ex){
ex.printStackTrace();
}
return restApiResult;
}
}
@Autowired
IAccountFeignClient accountFeignClient;
 这个是服务发现用的Feign的客户端，看一下它的实现：

package com.mallapp.client;

import com.mallapp.client.hystrix.AccountFeignClientHystrix;
import org.springframework.cloud.netflix.feign.FeignClient;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestMethod;
import org.springframework.web.bind.annotation.RequestParam;

@FeignClient(name="ACCOUNT-SERVICE", fallback = AccountFeignClientHystrix.class)
public interface IAccountFeignClient {
@RequestMapping(value = "/acc/signup",method = RequestMethod.GET)
public String signUp(@RequestParam(value = "phone") String phone, @RequestParam(value = "password") String password);
@RequestMapping(value = "/acc/login",method = RequestMethod.POST)
public String login(@RequestParam(value = "phone") String phone, @RequestParam(value = "password") String password);
}
这个接口必须和服务提供端的controller类的接口完全一致，而且参数注解一定完全一致。

看下SpringCloud所说的断路器类的实现：（意义就是服务消费者端调用服务提供端的时候，调用超时或者服务器异常等，会直接通过此接口返回响应）

package com.mallapp.client.hystrix;

import com.common.constant.RestApiResult;
import com.common.constant.ReturnCode;
import com.google.gson.Gson;
import com.mallapp.client.IAccountFeignClient;
import org.springframework.stereotype.Component;

@Component
public class AccountFeignClientHystrix implements IAccountFeignClient {
@Override
public String signUp(String phone, String password) {
return new Gson().toJson(new RestApiResult(false, ReturnCode.SYSTEM_ERROR,"The server is busy now......"));
}

@Override
public String login(String phone, String password) {
return new Gson().toJson(new RestApiResult(false, ReturnCode.SYSTEM_ERROR,"The server is busy now......"));
}
}

看下所说的AOP中的前置通知、后置通知、环绕通知等实现类：

package com.mallapp.aop;

import com.common.constant.RestApiResult;
import com.common.constant.ReturnCode;
import com.mallapp.Security.JWTUtils;
import io.jsonwebtoken.ExpiredJwtException;
import io.jsonwebtoken.MalformedJwtException;
import io.jsonwebtoken.SignatureException;
import io.jsonwebtoken.UnsupportedJwtException;
import org.aspectj.lang.JoinPoint;
import org.aspectj.lang.ProceedingJoinPoint;
import org.aspectj.lang.annotation.After;
import org.aspectj.lang.annotation.Around;
import org.aspectj.lang.annotation.Aspect;
import org.aspectj.lang.annotation.Before;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.stereotype.Component;
import org.springframework.web.context.request.RequestAttributes;
import org.springframework.web.context.request.RequestContextHolder;
import org.springframework.web.context.request.ServletRequestAttributes;

import javax.servlet.http.HttpServletRequest;
import java.util.Iterator;
import java.util.Map;

@Aspect
@Component
public class ApiExecuteNoticeService {
private final static Logger LOG = LoggerFactory.getLogger(ApiExecuteNoticeService.class);
private final static String access_token = "accessToken";

/**
* 方法之前执行
* @param joinPoint
* @throws Exception
*/
@Before("execution(public * com.mallapp.api.*.*(..))")
public void doBeforeInService(JoinPoint joinPoint)throws Exception{
System.out.println("Before to check the API......");
}

/**
* 方法之后执行
* @param joinPoint
* @throws Exception
*/
@After("execution(public * com.mallapp.api.*.*(..))")
public void AfterInService(JoinPoint joinPoint)throws Exception{
System.out.println("After to check the API......");
}

/**
* 环绕通知
* @param joinPoint
* @return
* @throws Exception
*/
@Around("execution(public * com.mallapp.api.*.*(..))")
public RestApiResult doAroundInService(ProceedingJoinPoint joinPoint)throws Exception{
System.out.println("Around to check the API......");
RequestAttributes requestAttributes = RequestContextHolder.getRequestAttributes();
ServletRequestAttributes servletRequestAttributes = (ServletRequestAttributes)requestAttributes;
HttpServletRequest request = servletRequestAttributes.getRequest();
String requestPath = request.getRequestURI();
System.out.println("uri: " + requestPath);
/*需要过滤不进行检查的url地址*/
// if (requestPath.contains("acc")){
// try {
// return (RestApiResult)joinPoint.proceed();
// } catch (Throwable throwable) {
// throwable.printStackTrace();
// }
// System.out.println("url /acc does not to check.");
// return null;
// }
Map<String,String[]> inputMap = request.getParameterMap();
Iterator<String> keyIter = inputMap.keySet().iterator();
boolean result = false;
while(keyIter.hasNext()){
String currKey = keyIter.next();
String value = ((String[])inputMap.get(currKey))[0].toString();
if (!access_token.equals(currKey)){
continue;
}
try{
JWTUtils.parseJWT(value);
System.out.println("cuurKey="+currKey+",value="+value);
result = true;
}catch(ExpiredJwtException ex){
ex.printStackTrace();
}catch (UnsupportedJwtException ex){
ex.printStackTrace();
}catch (MalformedJwtException ex){
ex.printStackTrace();
}catch (SignatureException ex){
ex.printStackTrace();
}catch (IllegalArgumentException ex){
ex.printStackTrace();
}
}
if (!result){
return new RestApiResult(false,ReturnCode.INVALID_VALUE,"token校验失败.");
}
try {
return (RestApiResult) joinPoint.proceed();
} catch (Throwable throwable) {
throwable.printStackTrace();
}
return new RestApiResult(false,ReturnCode.SYSTEM_ERROR,"unkonwn exception");
}
}
 token校验所涉及到类：

package com.mallapp.Security;

import javax.crypto.SecretKey;
import javax.crypto.spec.SecretKeySpec;

import io.jsonwebtoken.*;
import org.apache.tomcat.util.codec.binary.Base64;

import java.util.Date;
import java.util.UUID;

public class JWTUtils {
private final static String SECRETKEY = "OVlpXYjNwaFJYUllVbXhXTkZaR1pEQlNiVkYzWTBac1YxWkZXbE";
/**
* 由字符串生成加密key
*/
public static SecretKey generateKsy(String keyStr){
byte[] encodeKey = Base64.decodeBase64(keyStr);
SecretKey secretKey = new SecretKeySpec(encodeKey,0,encodeKey.length,"AES");
return secretKey;
}
/**
* 创建JWT，加密过程
*/
public static String createJWT(String id,String subject,long ttlMillis)throws Exception{
SignatureAlgorithm signatureAlgorithm = SignatureAlgorithm.HS256;
long nowMillis = System.currentTimeMillis();
Date now = new Date(nowMillis);
SecretKey key = generateKsy(SECRETKEY);
JwtBuilder jwtBuilder = Jwts.builder().setIssuer("").setId(id).setIssuedAt(now).setSubject(subject)
.signWith(signatureAlgorithm,key);
if (ttlMillis >= 0){
long expireMillis = nowMillis + ttlMillis;
Date expireDate = new Date(expireMillis);
jwtBuilder.setExpiration(expireDate);
}
return jwtBuilder.compact();
}
/**
* 解析JWT,解密过程
*/
public static Claims parseJWT(String jwt) throws ExpiredJwtException,UnsupportedJwtException,MalformedJwtException,
SignatureException,IllegalArgumentException{
SecretKey key = generateKsy(SECRETKEY);
Claims claims = Jwts.parser().setSigningKey(key).parseClaimsJws(jwt).getBody();
return claims;
}

// public static void main(String[] args){
// try{
// String token = createJWT(UUID.randomUUID().toString(),"",20000);
// System.out.println(token);
// Claims claims = parseJWT(token);
// System.out.println(claims.getExpiration()+" : "+claims.getExpiration().getTime());
// }catch (Exception ex){
// ex.printStackTrace();
// }
// }
}
 
UriFilterConfig类是用来接受Spring配置的xml文件的：urlifilter.properties

package com.mallapp.config;

import org.springframework.boot.context.properties.ConfigurationProperties;
import org.springframework.context.annotation.PropertySource;
import org.springframework.stereotype.Component;

import java.util.ArrayList;
import java.util.List;
import java.util.Set;

/**
* Created by c00415904 on 2018/5/29.
*/
@Component
@ConfigurationProperties(prefix = "url")
@PropertySource(value = {"classpath:urifilter.properties"} ,ignoreResourceNotFound = true)
public class UriFilterConfig {
private List<String> filterList = new ArrayList<String>();
public List<String> getFilterList() {
return filterList;
}

public void setFilter(List<String> filterList) {
this.filterList = filterList;
}
}
Awagger2Config类用来生成在线API文档： http://127.0.0.1:4444/swagger-ui.html 4444为消费者提供的端口号
package com.mallapp.config;

import io.swagger.annotations.ApiOperation;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import springfox.documentation.builders.ApiInfoBuilder;
import springfox.documentation.builders.PathSelectors;
import springfox.documentation.builders.RequestHandlerSelectors;
import springfox.documentation.service.ApiInfo;
import springfox.documentation.spi.DocumentationType;
import springfox.documentation.spring.web.plugins.Docket;
import springfox.documentation.swagger2.annotations.EnableSwagger2;

@Configuration
@EnableSwagger2
public class Awagger2Config {
@Bean
public Docket createRestApi(){
return new Docket(DocumentationType.SWAGGER_2).apiInfo(getApiInfo()).select()
.apis(RequestHandlerSelectors.basePackage("com.mallapp.api"))
.apis(RequestHandlerSelectors.withMethodAnnotation(ApiOperation.class))
.paths(PathSelectors.any())
.build();
}
private ApiInfo getApiInfo(){
return new ApiInfoBuilder().title("Mall App Swagger Apis").description("For mall-service 's app use")
.version("V1.0").build();
}
}

服务启动类：

FeignApplication

package com.mallapp;

import com.common.constant.SystemConstant;
import com.common.util.JedisUtil;
import com.mallapp.config.UriFilterConfig;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.boot.CommandLineRunner;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.cloud.client.discovery.EnableDiscoveryClient;
import org.springframework.cloud.netflix.eureka.EnableEurekaClient;
import org.springframework.cloud.netflix.feign.EnableFeignClients;

import java.util.Date;

@SpringBootApplication
@EnableFeignClients
@EnableEurekaClient
@EnableDiscoveryClient
public class FeignApplication implements CommandLineRunner{
@Autowired
private UriFilterConfig uriFilterConfig;
public static void main(String[] args){
SpringApplication.run(FeignApplication.class,args);
}
@Override
public void run(String... strings) throws Exception {
System.out.println("Begin to init data......"+new Date());
System.out.println(uriFilterConfig.getFilterList());
for(String url : uriFilterConfig.getFilterList()){
JedisUtil.SETS.sadd(SystemConstant.URL_NEED_CHECK_KEY,url);
}
}
}

我们分别启动服务消费者和服务提供者，然后进行postman测试或者前端测试：