content: /*
   * Copyright 1999-2019 Alibaba Group Holding Ltd.
   *
   * Licensed under the Apache License, Version 2.0 (the "License");
   * you may not use this file except in compliance with the License.
   * You may obtain a copy of the License at
   *
   *      https://www.apache.org/licenses/LICENSE-2.0
   *
   * Unless required by applicable law or agreed to in writing, software
   * distributed under the License is distributed on an "AS IS" BASIS,
   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
   * See the License for the specific language governing permissions and
   * limitations under the License.
   */
  package com.alibaba.csp.sentinel.demo.spring.sc.gateway;
  
  import java.util.Collections;
  import java.util.HashSet;
  import java.util.List;
  import java.util.Set;
  
  import javax.annotation.PostConstruct;
  
  import com.alibaba.csp.sentinel.adapter.gateway.common.SentinelGatewayConstants;
  import com.alibaba.csp.sentinel.adapter.gateway.common.api.ApiDefinition;
  import com.alibaba.csp.sentinel.adapter.gateway.common.api.ApiPathPredicateItem;
  import com.alibaba.csp.sentinel.adapter.gateway.common.api.ApiPredicateItem;
  import com.alibaba.csp.sentinel.adapter.gateway.common.api.GatewayApiDefinitionManager;
  import com.alibaba.csp.sentinel.adapter.gateway.common.rule.GatewayFlowRule;
  import com.alibaba.csp.sentinel.adapter.gateway.common.rule.GatewayParamFlowItem;
  import com.alibaba.csp.sentinel.adapter.gateway.common.rule.GatewayRuleManager;
  import com.alibaba.csp.sentinel.adapter.gateway.sc.SentinelGatewayFilter;
  import com.alibaba.csp.sentinel.adapter.gateway.sc.exception.SentinelGatewayBlockExceptionHandler;
  import com.alibaba.csp.sentinel.slots.block.RuleConstant;
  
  import org.springframework.beans.factory.ObjectProvider;
  import org.springframework.cloud.gateway.filter.GlobalFilter;
  import org.springframework.context.annotation.Bean;
  import org.springframework.context.annotation.Configuration;
  import org.springframework.core.Ordered;
  import org.springframework.core.annotation.Order;
  import org.springframework.http.codec.ServerCodecConfigurer;
  import org.springframework.web.reactive.result.view.ViewResolver;
  
  /**
   * @author Eric Zhao
   */
  @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;
      }
  
      @Bean
      @Order(Ordered.HIGHEST_PRECEDENCE)
      public SentinelGatewayBlockExceptionHandler sentinelGatewayBlockExceptionHandler() {
          // Register the block exception handler for Spring Cloud Gateway.
          return new SentinelGatewayBlockExceptionHandler(viewResolvers, serverCodecConfigurer);
      }
  
      @Bean
      @Order(-1)
      public GlobalFilter sentinelGatewayFilter() {
          return new SentinelGatewayFilter();
      }
  
      @PostConstruct
      public void doInit() {
          initCustomizedApis();
          initGatewayRules();
      }
  
      private void initCustomizedApis() {
          Set<ApiDefinition> definitions = new HashSet<>();
          ApiDefinition api1 = new ApiDefinition("some_customized_api")
              .setPredicateItems(new HashSet<ApiPredicateItem>() {{
                  add(new ApiPathPredicateItem().setPattern("/ahas"));
                  add(new ApiPathPredicateItem().setPattern("/product/**")
                      .setMatchStrategy(SentinelGatewayConstants.URL_MATCH_STRATEGY_PREFIX));
              }});
          ApiDefinition api2 = new ApiDefinition("another_customized_api")
              .setPredicateItems(new HashSet<ApiPredicateItem>() {{
                  add(new ApiPathPredicateItem().setPattern("/**")
                      .setMatchStrategy(SentinelGatewayConstants.URL_MATCH_STRATEGY_PREFIX));
              }});
          definitions.add(api1);
          definitions.add(api2);
          GatewayApiDefinitionManager.loadApiDefinitions(definitions);
      }
  
      private void initGatewayRules() {
          Set<GatewayFlowRule> rules = new HashSet<>();
          rules.add(new GatewayFlowRule("aliyun_route")
              .setCount(10)
              .setIntervalSec(1)
          );
          rules.add(new GatewayFlowRule("aliyun_route")
              .setCount(2)
              .setIntervalSec(2)
              .setBurst(2)
              .setParamItem(new GatewayParamFlowItem()
                  .setParseStrategy(SentinelGatewayConstants.PARAM_PARSE_STRATEGY_CLIENT_IP)
              )
          );
          rules.add(new GatewayFlowRule("httpbin_route")
              .setCount(10)
              .setIntervalSec(1)
              .setControlBehavior(RuleConstant.CONTROL_BEHAVIOR_RATE_LIMITER)
              .setMaxQueueingTimeoutMs(600)
              .setParamItem(new GatewayParamFlowItem()
                  .setParseStrategy(SentinelGatewayConstants.PARAM_PARSE_STRATEGY_HEADER)
                  .setFieldName("X-Sentinel-Flag")
              )
          );
          rules.add(new GatewayFlowRule("httpbin_route")
              .setCount(1)
              .setIntervalSec(1)
              .setParamItem(new GatewayParamFlowItem()
                  .setParseStrategy(SentinelGatewayConstants.PARAM_PARSE_STRATEGY_URL_PARAM)
                  .setFieldName("pa")
              )
          );
          rules.add(new GatewayFlowRule("httpbin_route")
              .setCount(2)
              .setIntervalSec(30)
              .setParamItem(new GatewayParamFlowItem()
                  .setParseStrategy(SentinelGatewayConstants.PARAM_PARSE_STRATEGY_URL_PARAM)
                  .setFieldName("type")
                  .setPattern("warn")
                  .setMatchStrategy(SentinelGatewayConstants.PARAM_MATCH_STRATEGY_CONTAINS)
              )
          );
  
          rules.add(new GatewayFlowRule("some_customized_api")
              .setResourceMode(SentinelGatewayConstants.RESOURCE_MODE_CUSTOM_API_NAME)
              .setCount(5)
              .setIntervalSec(1)
              .setParamItem(new GatewayParamFlowItem()
                  .setParseStrategy(SentinelGatewayConstants.PARAM_PARSE_STRATEGY_URL_PARAM)
                  .setFieldName("pn")
              )
          );
          GatewayRuleManager.loadRules(rules);
      }
  }
  