<dependency>
	<groupId>com.alibaba.csp</groupId>
	<artifactId>sentinel-spring-cloud-gateway-adapter</artifactId>
</dependency>

@Configuration
public class GatewayConfiguration {
    private final List<ViewResolver> viewResolvers;
    private final ServerCodecConfigurer serverCodecConfigurer;

    public GatewayConfiguration(ObjectProvider<List<ViewResolver>> viewResolversProvider, ServerCodecConfigurer serverCodecConfigurer) {
        this.viewResolvers = viewResolversProvider.getIfAvailable(Collections::emptyList);
        this.serverCodecConfigurer = serverCodecConfigurer;
    }

    //初始化一個限流的過濾器
    @Bean
    @Order(Ordered.HIGHEST_PRECEDENCE)
    public GlobalFilter sentinelGatewayFilter() {
        return new SentinelGatewayFilter();
    }

    //配置初始化的限流參數(shù)
    @PostConstruct
    public void initGatewayRules() {
        Set<GatewayFlowRule> rules = new HashSet<>();
        rules.add(new GatewayFlowRule("shop-product")//資源名稱,對應路由id
                        .setCount(1)//限流閥值
                        .setIntervalSec(1)//統(tǒng)計時間窗口,單位是秒,默認是1秒
        );
        GatewayRuleManager.loadRules(rules);
    }


    //配置限流異常處理器
    @Bean
    @Order(Ordered.HIGHEST_PRECEDENCE)
    public SentinelGatewayBlockExceptionHandler sentinelGatewayBlockExceptionHandler() {
        return new SentinelGatewayBlockExceptionHandler(viewResolvers, serverCodecConfigurer);
    }

    //自定義限流異常頁面
    @PostConstruct
    public void initBlockHandlers() {
        BlockRequestHandler blockRequestHandler = new BlockRequestHandler() {
            @Override
            public Mono<ServerResponse> handleRequest(ServerWebExchange serverWebExchange, Throwable throwable) {
                Map map= new HashMap<>();
                map.put("code", 0);
                map.put("message", "接口被限流了");
                return ServerResponse
                        .status(HttpStatus.OK)
                        .contentType(MediaType.APPLICATION_JSON_UTF8)
                        .body(BodyInserters.fromObject(map));
            }
        } ;
        GatewayCallbackManager.setBlockHandler(blockRequestHandler);
    }
}

//配置初始化的限流參數(shù)
@PostConstruct
public void initGatewayRules() {
    Set<GatewayFlowRule> rules = new HashSet<>();
    rules.add(new GatewayFlowRule("shop_product_api").setCount(1).setIntervalSec(1));
    rules.add(new GatewayFlowRule("shop_order_api").setCount(1).setIntervalSec(1));
    GatewayRuleManager.loadRules(rules);
}

//自定義API分組
@PostConstruct
private void initCustomizedApis(){
    Set<ApiDefinition> definitions = new HashSet<>();
    //定義小組1
    ApiDefinition api1 = new ApiDefinition("shop_product_api")
            .setPredicateItems(new HashSet<ApiPredicateItem>(){{
                //以/product/product/api1開頭的請求
                add(new ApiPathPredicateItem().setPattern("/product/product/**")
                        .setMatchStrategy(SentinelGatewayConstants.URL_MATCH_STRATEGY_PREFIX));
            }});
    //定義小組2
    ApiDefinition api2 = new ApiDefinition("shop_order_api")
            .setPredicateItems(new HashSet<ApiPredicateItem>(){{
                //完全匹配/order/order2/message
                add(new ApiPathPredicateItem().setPattern("/order/order2/message"));
            }});
    definitions.add(api1);
    definitions.add(api2);
    GatewayApiDefinitionManager.loadApiDefinitions(definitions);
}