[Java] 详解Spring Cloud Gateway 数据库存储路由信息的扩展方案

# zuul 的配置形式
routes:
 pig-auth:
  path: /auth/**
  serviceid: pig-auth
  stripprefix: true
# gateway 的配置形式
routes:
- id: pigx-auth
  uri: lb://pigx-auth
 predicates:
 - path=/auth/**
 filters:
 - validatecodegatewayfilter

• dispatcherhandler 接管用户请求
  
• routepredicatehandlermapping 路由匹配
  
  
  • 根据routelocator获取 routedefinitionlocator
    
  • 返回多个routedefinitionlocator.getroutedefinitions()的路由定义信息
    
  
  
• filteringwebhandler执行路由定义中的filter 最后路由到具体的业务服务中
  

// 上图动态路由的信息保存的默认实现是基于内存的实现
public class inmemoryroutedefinitionrepository implements routedefinitionrepository {
  private final map<string, routedefinition> routes = synchronizedmap(new linkedhashmap<string, routedefinition>());
  @override
  public mono<void> save(mono<routedefinition> route){}
  @override
  public mono<void> delete(mono<string> routeid){}
 
  @override
  public flux<routedefinition> getroutedefinitions(){}
}

• spring cloud gateway 基于webflux 背压，暂时不支持mysql 数据库
  
• redis-reactive 支持 spring cloudgateway 的背压，同时还可以实现分布式，高性能
  

• 增加一个路由管理模块，参考gatewaycontrollerendpoint实现，启动时加载数据库中配置文件到redis
  
• 网关模块重写routedefinitionrepository，getroutedefinitions（）取redis中读取即可实现
  
• 前端配合 json-view 类似插件，直接修改展示。
  

/**
 * @author lengleng
 * @date 2018年11月06日10:27:55
 * <p>
 * 动态路由处理类
 */
@slf4j
@allargsconstructor
@service("sysrouteconfservice")
public class sysrouteconfserviceimpl extends serviceimpl<sysrouteconfmapper, sysrouteconf> implements sysrouteconfservice {
  private final redistemplate redistemplate;
  private final applicationeventpublisher applicationeventpublisher;
 
  /**
   * 获取全部路由
   * <p>
   * redisroutedefinitionwriter.java
   * propertiesroutedefinitionlocator.java
   *
   * @return
   */
  @override
  public list<sysrouteconf> routes() {
  sysrouteconf condition = new sysrouteconf();
  condition.setdelflag(commonconstant.status_normal);
  return basemapper.selectlist(new entitywrapper<>(condition));
  }
 
  /**
   * 更新路由信息
   *
   * @param routes 路由信息
   * @return
   */
  @override
  public mono<void> editroutes(jsonarray routes) {
  // 清空redis 缓存
  boolean result = redistemplate.delete(commonconstant.route_key);
  log.info("清空网关路由 {} ", result);
 
  // 遍历修改的routes，保存到redis
  list<routedefinitionvo> routedefinitionvolist = new arraylist<>();
  routes.foreach(value -> {
    log.info("更新路由 ->{}", value);
    routedefinitionvo vo = new routedefinitionvo();
    map<string, object> map = (map) value;
 
    object id = map.get("routeid");
    if (id != null) {
    vo.setid(string.valueof(id));
    }
 
    object predicates = map.get("predicates");
    if (predicates != null) {
    jsonarray predicatesarray = (jsonarray) predicates;
    list<predicatedefinition> predicatedefinitionlist =
      predicatesarray.tolist(predicatedefinition.class);
    vo.setpredicates(predicatedefinitionlist);
    }
 
    object filters = map.get("filters");
    if (filters != null) {
    jsonarray filtersarray = (jsonarray) filters;
    list<filterdefinition> filterdefinitionlist
      = filtersarray.tolist(filterdefinition.class);
    vo.setfilters(filterdefinitionlist);
    }
 
    object uri = map.get("uri");
    if (uri != null) {
    vo.seturi(uri.create(string.valueof(uri)));
    }
 
    object order = map.get("order");
    if (order != null) {
    vo.setorder(integer.parseint(string.valueof(order)));
    }
 
    redistemplate.sethashvalueserializer(new jackson2jsonredisserializer<>(routedefinitionvo.class));
    redistemplate.opsforhash().put(commonconstant.route_key, vo.getid(), vo);
    routedefinitionvolist.add(vo);
  });
 
  // 逻辑删除全部
  sysrouteconf condition = new sysrouteconf();
  condition.setdelflag(commonconstant.status_normal);
  this.delete(new entitywrapper<>(condition));
 
  //插入生效路由
  list<sysrouteconf> routeconflist = routedefinitionvolist.stream().map(vo -> {
    sysrouteconf routeconf = new sysrouteconf();
    routeconf.setrouteid(vo.getid());
    routeconf.setfilters(jsonutil.tojsonstr(vo.getfilters()));
    routeconf.setpredicates(jsonutil.tojsonstr(vo.getpredicates()));
    routeconf.setorder(vo.getorder());
    routeconf.seturi(vo.geturi().tostring());
    return routeconf;
  }).collect(collectors.tolist());
  this.insertbatch(routeconflist);
  log.debug("更新网关路由结束 ");
 
  this.applicationeventpublisher.publishevent(new refreshroutesevent(this));
  return mono.empty();
  }
}

@slf4j
@component
@allargsconstructor
public class redisroutedefinitionwriter implements routedefinitionrepository {
  private final redistemplate redistemplate;
 
  @override
  public mono<void> save(mono<routedefinition> route) {
  return route.flatmap(r -> {
    routedefinitionvo vo = new routedefinitionvo();
    beanutils.copyproperties(r, vo);
    log.info("保存路由信息{}", vo);
    redistemplate.opsforhash().put(commonconstant.route_key, r.getid(), vo);
    return mono.empty();
  });
  }
  @override
  public mono<void> delete(mono<string> routeid) {
  routeid.subscribe(id -> {
    log.info("删除路由信息{}", id);
    redistemplate.opsforhash().delete(commonconstant.route_key, id);
  });
  return mono.empty();
  }
 
  @override
  public flux<routedefinition> getroutedefinitions() {
  redistemplate.sethashvalueserializer(new jackson2jsonredisserializer<>(routedefinitionvo.class));
  list<routedefinitionvo> values = redistemplate.opsforhash().values(commonconstant.route_key);
  list<routedefinition> definitionlist = new arraylist<>();
  values.foreach(vo -> {
    routedefinition routedefinition = new routedefinition();
    beanutils.copyproperties(vo, routedefinition);
    definitionlist.add(vo);
  });
  log.debug("redis 中路由定义条数： {}， {}", definitionlist.size(), definitionlist);
  return flux.fromiterable(definitionlist);
  }
}