Spring Cloud Gateway集成Sentinel，限流

1、添加依赖

		
			com.alibaba.csp
			sentinel-core
			1.6.3
		
		
			com.alibaba.csp
			sentinel-spring-cloud-gateway-adapter
			1.6.3
		
		
			com.alibaba.csp
			sentinel-transport-simple-http
			1.6.3
		

添加限流规则，设置限流参数

//设置API
Set definitions = new HashSet<>();
ApiDefinition api1 = new ApiDefinition("account_api")
        .setPredicateItems(new HashSet() {{
            add(new ApiPathPredicateItem().setPattern("/api/v1/account/**")
                    .setMatchStrategy(SentinelGatewayConstants.URL_MATCH_STRATEGY_PREFIX));
        }});


//设置规则
rules.add(new GatewayFlowRule("userplatform")
        .setCount(2)
        .setIntervalSec(1)
);

rules.add(new GatewayFlowRule("account_api")
        .setResourceMode(SentinelGatewayConstants.RESOURCE_MODE_CUSTOM_API_NAME)
        .setCount(5)
        .setIntervalSec(1)
);

具体配置类

@Configuration
public class GatewayConfiguration {

    private String RESOURCE_NAME = "xxxA";
    private final List viewResolvers;
    private final ServerCodecConfigurer serverCodecConfigurer;

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

    @Bean
    @Order(Ordered.HIGHEST_PRECEDENCE)
    public SentinelGatewayBlockExceptionHandler sentinelGatewayBlockExceptionHandler() {
        // Register the block exception handler for Spring Cloud Gateway.
        return new SentinelGatewayBlockExceptionHandler(viewResolvers, serverCodecConfigurer);
    }

    @Bean
    @Order(-5)
    public GlobalFilter sentinelGatewayFilter() {
        return new SentinelGatewayFilter();
    }

    @PostConstruct
    public void doInit() {
        initCustomizedApis();
        initGatewayRules();
    }

    private void initCustomizedApis() {
        Set definitions = new HashSet<>();
        ApiDefinition api1 = new ApiDefinition("account_api")
                .setPredicateItems(new HashSet() {{
                    add(new ApiPathPredicateItem().setPattern("/api/v1/account/**")
                            .setMatchStrategy(SentinelGatewayConstants.URL_MATCH_STRATEGY_PREFIX));
                }});

        ApiDefinition api2 = new ApiDefinition("account_api_limit_accountId")
                .setPredicateItems(new HashSet() {{
                    add(new ApiPathPredicateItem().setPattern("/api/v1/account/**")
                            .setMatchStrategy(SentinelGatewayConstants.URL_MATCH_STRATEGY_PREFIX));
                }});
        definitions.add(api1);
        definitions.add(api2);
        GatewayApiDefinitionManager.loadApiDefinitions(definitions);
    }

    private void initGatewayRules() {
        Set rules = new HashSet<>();
        rules.add(new GatewayFlowRule("userplatform")
                .setCount(2)
                .setIntervalSec(1)
        );

        rules.add(new GatewayFlowRule("account_api")
                .setResourceMode(SentinelGatewayConstants.RESOURCE_MODE_CUSTOM_API_NAME)
                .setCount(3)
                .setIntervalSec(1)
        );

       /* rules.add(new GatewayFlowRule("account_api_limit_accountId")
                .setResourceMode(SentinelGatewayConstants.RESOURCE_MODE_CUSTOM_API_NAME)
                .setCount(1)
                .setIntervalSec(1)
                .setParamItem(new GatewayParamFlowItem()
                        .setParseStrategy(SentinelGatewayConstants.PARAM_PARSE_STRATEGY_URL_PARAM)
                        .setFieldName("accountId")
                )
        );*/
        GatewayRuleManager.loadRules(rules);
    }

}

2、启动dashboard

dashboard下载地址：Sentinel releases
java -Dserver.port=8080 -Dproject.name=sentinel-dashboard-test -jar ~/soft/sentinel-dashboard-1.6.3.jar
浏览器访问：localhost:8080 默认用户名和密码都是sentinel。
连接dashboard

3、在gateway项目中添加JVM参数

-Djava.net.preferIPv4Stack=true -Dcsp.sentinel.dashboard.server=localhost:8080 -Dcsp.sentinel.api.port=8666 -Dproject.name=MYAPP -Dcsp.sentinel.app.type=1
例如idea中添加JVM参数

说明：-Dcsp.sentinel.app.type=1 这个参数是Gateway接入Sentinel才需要配置，配置上之后dashboard会展示出为gateway特别定制的界面。而且这个功能在1.6.3版本才有，于2019.07合入的新功能。

4、触发客户端连接控制台

客户端配置好了与控制台的连接参数之后，并不会主动连接上控制台，需要触发一次客户端的规则才会开始进行初始化，并向控制台发送心跳和客户端规则等信息。（注意）

流控规则：

5、请求链路：

6、API管理：

7、更改流控规则

动态生效，限流后会报Blocked by Sentinel: ParamFlowException异常。
可以针对请求头中的参数如Authorization，请求参数名和参数值，uri，ip等进行限流。

8、实时监控