content: /*
   * Copyright 2013-2023 the original author or authors.
   *
   * 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.cloud.nacos.loadbalancer;
  
  import java.util.HashMap;
  import java.util.List;
  import java.util.Map;
  
  import com.alibaba.cloud.nacos.NacosDiscoveryProperties;
  import com.alibaba.cloud.nacos.util.InetIPv6Utils;
  
  import org.springframework.boot.autoconfigure.condition.ConditionalOnBean;
  import org.springframework.boot.autoconfigure.condition.ConditionalOnMissingBean;
  import org.springframework.boot.autoconfigure.condition.ConditionalOnProperty;
  import org.springframework.cloud.client.ConditionalOnBlockingDiscoveryEnabled;
  import org.springframework.cloud.client.ConditionalOnDiscoveryEnabled;
  import org.springframework.cloud.client.ConditionalOnReactiveDiscoveryEnabled;
  import org.springframework.cloud.client.ServiceInstance;
  import org.springframework.cloud.client.discovery.DiscoveryClient;
  import org.springframework.cloud.client.discovery.ReactiveDiscoveryClient;
  import org.springframework.cloud.loadbalancer.core.ReactorLoadBalancer;
  import org.springframework.cloud.loadbalancer.core.ServiceInstanceListSupplier;
  import org.springframework.cloud.loadbalancer.support.LoadBalancerClientFactory;
  import org.springframework.context.ConfigurableApplicationContext;
  import org.springframework.context.annotation.Bean;
  import org.springframework.context.annotation.Configuration;
  import org.springframework.core.annotation.Order;
  import org.springframework.core.env.Environment;
  
  /**
   * {@link ServiceInstanceListSupplier} don't use cache.<br>
   * <br>
   * 1. LoadBalancerCache causes information such as the weight of the service instance to
   * be changed without immediate effect.<br>
   * 2. Nacos itself supports caching.
   *
   * @author XuDaojie
   * @since 2021.1
   */
  @Configuration(proxyBeanMethods = false)
  @ConditionalOnLoadBalancerNacos
  @ConditionalOnDiscoveryEnabled
  public class NacosLoadBalancerClientConfiguration {
  
  	private static final int REACTIVE_SERVICE_INSTANCE_SUPPLIER_ORDER = 183827465;
  
  	@Bean
  	@ConditionalOnMissingBean
  	public ReactorLoadBalancer<ServiceInstance> nacosLoadBalancer(Environment environment,
  			LoadBalancerClientFactory loadBalancerClientFactory,
  			NacosDiscoveryProperties nacosDiscoveryProperties,
  			InetIPv6Utils inetIPv6Utils,
  			List<ServiceInstanceFilter> serviceInstanceFilters,
  			List<LoadBalancerAlgorithm> loadBalancerAlgorithms) {
  		String name = environment.getProperty(LoadBalancerClientFactory.PROPERTY_NAME);
  		Map<String, LoadBalancerAlgorithm> loadBalancerAlgorithmMap = new HashMap<>();
  		loadBalancerAlgorithms.forEach(loadBalancerAlgorithm -> {
  			if (!loadBalancerAlgorithmMap.containsKey(loadBalancerAlgorithm.getServiceId())) {
  				loadBalancerAlgorithmMap.put(loadBalancerAlgorithm.getServiceId(), loadBalancerAlgorithm);
  			}
  		});
  		return new NacosLoadBalancer(
  				loadBalancerClientFactory.getLazyProvider(name,
  						ServiceInstanceListSupplier.class),
  				name, nacosDiscoveryProperties, inetIPv6Utils,
  				serviceInstanceFilters, loadBalancerAlgorithmMap);
  	}
  
  	@Configuration(proxyBeanMethods = false)
  	@ConditionalOnReactiveDiscoveryEnabled
  	@Order(REACTIVE_SERVICE_INSTANCE_SUPPLIER_ORDER)
  	public static class ReactiveSupportConfiguration {
  
  		@Bean
  		@ConditionalOnBean(ReactiveDiscoveryClient.class)
  		@ConditionalOnMissingBean
  		@ConditionalOnProperty(value = "spring.cloud.loadbalancer.configurations", havingValue = "default", matchIfMissing = true)
  		public ServiceInstanceListSupplier discoveryClientServiceInstanceListSupplier(
  				ConfigurableApplicationContext context) {
  			return ServiceInstanceListSupplier.builder().withDiscoveryClient()
  					.build(context);
  		}
  
  		@Bean
  		@ConditionalOnBean(ReactiveDiscoveryClient.class)
  		@ConditionalOnMissingBean
  		@ConditionalOnProperty(value = "spring.cloud.loadbalancer.configurations", havingValue = "zone-preference")
  		public ServiceInstanceListSupplier zonePreferenceDiscoveryClientServiceInstanceListSupplier(
  				ConfigurableApplicationContext context) {
  			return ServiceInstanceListSupplier.builder().withDiscoveryClient()
  					.withZonePreference().build(context);
  		}
  
  	}
  
  	@Configuration(proxyBeanMethods = false)
  	@ConditionalOnBlockingDiscoveryEnabled
  	@Order(REACTIVE_SERVICE_INSTANCE_SUPPLIER_ORDER + 1)
  	public static class BlockingSupportConfiguration {
  
  		@Bean
  		@ConditionalOnBean(DiscoveryClient.class)
  		@ConditionalOnMissingBean
  		@ConditionalOnProperty(value = "spring.cloud.loadbalancer.configurations", havingValue = "default", matchIfMissing = true)
  		public ServiceInstanceListSupplier discoveryClientServiceInstanceListSupplier(
  				ConfigurableApplicationContext context) {
  			return ServiceInstanceListSupplier.builder().withBlockingDiscoveryClient()
  					.build(context);
  		}
  
  		@Bean
  		@ConditionalOnBean(DiscoveryClient.class)
  		@ConditionalOnMissingBean
  		@ConditionalOnProperty(value = "spring.cloud.loadbalancer.configurations", havingValue = "zone-preference")
  		public ServiceInstanceListSupplier zonePreferenceDiscoveryClientServiceInstanceListSupplier(
  				ConfigurableApplicationContext context) {
  			return ServiceInstanceListSupplier.builder().withBlockingDiscoveryClient()
  					.withZonePreference().build(context);
  		}
  	}
  }
  