深入Java微服务之网关系列2：常见Java网关实现方案对比

@RequestMapping(value = {"/getUser"}, method = RequestMethod.GET)
    public String getUser() {
        Map<String ,String> user = new HashMap<>();
        user.put("name", "张三");
        user.put("age", "45");
        String s = JSONObject.toJSONString(user);
        return s;
    }
复制代码

        <dependency>
            <groupId>org.springframework.cloud</groupId>
            spring-cloud-starter-gateway
            <version>2.0.4.RELEASE</version>
        </dependency>
复制代码

spring:
  cloud:
    gateway:
      routes:
      - predicates:
            - Path =/gateway/**  #匹配规则
        uri: http://localhost:8099/getUser    #服务1的访问地址
        filters:
            - StripRrefix: 1 #去掉前缀
 server：
    port: 8077
复制代码

/**
 * 动态路由服务
 */
@Service
public class GoRouteServiceImpl implements ApplicationEventPublisherAware {
    @Autowired
    private RouteDefinitionWriter routeDefinitionWriter;
    private ApplicationEventPublisher publisher;
    @Override
    public void setApplicationEventPublisher(ApplicationEventPublisher applicationEventPublisher) {
        this.publisher = applicationEventPublisher;
    }
    //增加路由
    public String add(RouteDefinition definition) {
        routeDefinitionWriter.save(Mono.just(definition)).subscribe();
        this.publisher.publishEvent(new RefreshRoutesEvent(this));
        return "success";
    }
    //更新路由
    public String update(RouteDefinition definition) {
        try {
            delete(definition.getId());
        } catch (Exception e) {
            return "update fail,not find route  routeId: "+definition.getId();
        }
        try {
            routeDefinitionWriter.save(Mono.just(definition)).subscribe();
            this.publisher.publishEvent(new RefreshRoutesEvent(this));
            return "success";
        } catch (Exception e) {
            return "update route  fail";
        }
    }
    //删除路由
    public Mono<ResponseEntity<Object>> delete(String id) {
        return this.routeDefinitionWriter.delete(Mono.just(id)).then(Mono.defer(() -> {
            return Mono.just(ResponseEntity.ok().build());
        })).onErrorResume((t) -> {
            return t instanceof NotFoundException;
        }, (t) -> {
            return Mono.just(ResponseEntity.notFound().build());
        });
    }
}
复制代码

@RestController
@RequestMapping("/changeRoute")
public class ChangeRouteController {
    @Autowired
    private GoRouteServiceImpl goRouteServiceImpl;
    //增加路由
    @PostMapping("/add")
    public String add(@RequestBody GatewayRouteDefinition gwdefinition) {
        String flag = "fail";
        try {
            RouteDefinition definition = assembleRouteDefinition(gwdefinition);
            flag = this.goRouteService.add(definition);
        } catch (Exception e) {
            e.printStackTrace();
        }
        return flag;
    }
    //删除路由
    @DeleteMapping("/routes/{id}")
    public Mono<ResponseEntity<Object>> delete(@PathVariable String id) {
        try {
            return this.goRouteService.delete(id);
        }catch (Exception e){
            e.printStackTrace();
        }
        return null;
    }
    //更新路由
    @PostMapping("/update")
    public String update(@RequestBody GatewayRouteDefinition gwdefinition) {
        RouteDefinition definition = assembleRouteDefinition(gwdefinition);
        return this.goRouteService.update(definition);
    }
    //把传递进来的参数转换成路由对象
    private RouteDefinition assembleRouteDefinition(GatewayRouteDefinition gwdefinition) {
        RouteDefinition definition = new RouteDefinition();
        definition.setId(gwdefinition.getId());
        definition.setOrder(gwdefinition.getOrder());
        //设置断言
        List<PredicateDefinition> pdList=new ArrayList<>();
        List<GatewayPredicateDefinition> gatewayPredicateDefinitionList=gwdefinition.getPredicates();
        for (GatewayPredicateDefinition gpDefinition: gatewayPredicateDefinitionList) {
            PredicateDefinition predicate = new PredicateDefinition();
            predicate.setArgs(gpDefinition.getArgs());
            predicate.setName(gpDefinition.getName());
            pdList.add(predicate);
        }
        definition.setPredicates(pdList);
        //设置过滤器
        List<FilterDefinition> filters = new ArrayList();
        List<GatewayFilterDefinition> gatewayFilters = gwdefinition.getFilters();
        for(GatewayFilterDefinition filterDefinition : gatewayFilters){
            FilterDefinition filter = new FilterDefinition();
            filter.setName(filterDefinition.getName());
            filter.setArgs(filterDefinition.getArgs());
            filters.add(filter);
        }
        definition.setFilters(filters);
        URI uri = null;
        if(gwdefinition.getUri().startsWith("http")){
            uri = UriComponentsBuilder.fromHttpUrl(gwdefinition.getUri()).build().toUri();
        }else{
            // uri为 lb://consumer-service 时使用下面的方法
            uri = URI.create(gwdefinition.getUri());
        }
        definition.setUri(uri);
        return definition;
    }
}
复制代码

@Service
@Slf4j
public class AllDefineFilter implements GlobalFilter,Ordered{
    @Override
    public Mono<Void> filter(ServerWebExchange exchange, GatewayFilterChain chain) {
        log.info("[pre]-Enter AllDefineFilter");
        return chain.filter(exchange).then(Mono.fromRunnable(()->{
            log.info("[post]-Return Result");
        }));
    }
    @Override
    public int getOrder() {
        return 0;
    }
}
复制代码

@Component
@Slf4j
public class UserDefineGatewayFilter extends AbstractGatewayFilterFactory<UserDefineGatewayFilter.GpConfig>{

    public UserDefineGatewayFilter(){
        super(GpConfig.class);
    }

    @Override
    public GatewayFilter apply(GpConfig config) {
        return ((exchange, chain) -> {
            log.info("[Pre] Filter Request,name:"+config.getName());
            return chain.filter(exchange).then(Mono.fromRunnable(()->{
                log.info("[Post] Response Filter");
            }));
        });
    }

    public static class UserConfig{
        private String name;

        public String getName() {
            return name;
        }

        public void setName(String name) {
            this.name = name;
        }
    }
}
复制代码