增加基于Region的权重流量策略

discovery-common/src/main/java/com/nepxion/discovery/common/entity/RegionWeightEntity.java

+package com.nepxion.discovery.common.entity;
+
+/**
+ * <p>Title: Nepxion Discovery</p>
+ * <p>Description: Nepxion Discovery</p>
+ * <p>Copyright: Copyright (c) 2017-2050</p>
+ * <p>Company: Nepxion</p>
+ * @author Haojun Ren
+ * @version 1.0
+ */
+
+import java.io.Serializable;
+import java.util.Map;
+
+import org.apache.commons.lang3.builder.EqualsBuilder;
+import org.apache.commons.lang3.builder.HashCodeBuilder;
+import org.apache.commons.lang3.builder.ToStringBuilder;
+import org.apache.commons.lang3.builder.ToStringStyle;
+
+public class RegionWeightEntity implements Serializable {
+    private static final long serialVersionUID = 3356648245119125011L;
+
+    private Map<String, Integer> weightMap;
+
+    public Map<String, Integer> getWeightMap() {
+        return weightMap;
+    }
+
+    public void setWeightMap(Map<String, Integer> weightMap) {
+        this.weightMap = weightMap;
+    }
+
+    @Override
+    public int hashCode() {
+        return HashCodeBuilder.reflectionHashCode(this);
+    }
+
+    @Override
+    public boolean equals(Object object) {
+        return EqualsBuilder.reflectionEquals(this, object);
+    }
+
+    @Override
+    public String toString() {
+        return ToStringBuilder.reflectionToString(this, ToStringStyle.MULTI_LINE_STYLE);
+    }
+}
\ No newline at end of file

discovery-common/src/main/java/com/nepxion/discovery/common/entity/WeightFilterEntity.java

@@ -14,6 +14,7 @@ import java.util.LinkedHashMap;
 import java.util.List;
 import java.util.Map;
 
+import org.apache.commons.collections4.MapUtils;
 import org.apache.commons.lang3.builder.EqualsBuilder;
 import org.apache.commons.lang3.builder.HashCodeBuilder;
 import org.apache.commons.lang3.builder.ToStringBuilder;
@@ -23,6 +24,7 @@ public class WeightFilterEntity implements Serializable {
     private static final long serialVersionUID = 7313443273653189837L;
 
     private Map<String, List<WeightEntity>> weightEntityMap = new LinkedHashMap<String, List<WeightEntity>>();
+    private RegionWeightEntity regionWeightEntity;
 
     public Map<String, List<WeightEntity>> getWeightEntityMap() {
         return weightEntityMap;
@@ -32,6 +34,18 @@ public class WeightFilterEntity implements Serializable {
         this.weightEntityMap = weightEntityMap;
     }
 
+    public RegionWeightEntity getRegionWeightEntity() {
+        return regionWeightEntity;
+    }
+
+    public void setRegionWeightEntity(RegionWeightEntity regionWeightEntity) {
+        this.regionWeightEntity = regionWeightEntity;
+    }
+
+    public boolean hasWeight() {
+        return MapUtils.isNotEmpty(weightEntityMap) || regionWeightEntity != null;
+    }
+
     @Override
     public int hashCode() {
         return HashCodeBuilder.reflectionHashCode(this);

discovery-common/src/main/java/com/nepxion/discovery/common/util/JsonUtil.java

@@ -9,20 +9,43 @@ package com.nepxion.discovery.common.util;
  * @version 1.0
  */
 
+import java.io.IOException;
+
 import org.apache.commons.lang3.StringUtils;
 
+import com.fasterxml.jackson.core.JsonGenerator;
 import com.fasterxml.jackson.core.JsonProcessingException;
 import com.fasterxml.jackson.core.type.TypeReference;
 import com.fasterxml.jackson.databind.ObjectMapper;
+import com.fasterxml.jackson.databind.SerializerProvider;
+import com.fasterxml.jackson.databind.ser.std.StdSerializer;
 
 public class JsonUtil {
     private static ObjectMapper objectMapper;
 
     static {
         objectMapper = new ObjectMapper();
+        // objectMapper.getSerializerProvider().setNullKeySerializer(new NullKeySerializer());
         // objectMapper.setDateFormat(new SimpleDateFormat(DiscoveryConstant.DATE_FORMAT));
     }
 
+    public static class NullKeySerializer extends StdSerializer<Object> {
+        private static final long serialVersionUID = -9176767187240330396L;
+
+        public NullKeySerializer() {
+            this(null);
+        }
+
+        public NullKeySerializer(Class<Object> object) {
+            super(object);
+        }
+
+        @Override
+        public void serialize(Object value, JsonGenerator gen, SerializerProvider provider) throws IOException {
+            gen.writeFieldName(StringUtils.EMPTY);
+        }
+    }
+
     public static <T> String toJson(T object) {
         if (object == null) {
             throw new IllegalArgumentException("Object is null");

discovery-plugin-admin-center/src/main/java/com/nepxion/discovery/plugin/admincenter/endpoint/RouterEndpoint.java

@@ -40,6 +40,7 @@ import com.fasterxml.jackson.core.type.TypeReference;
 import com.nepxion.discovery.common.constant.DiscoveryConstant;
 import com.nepxion.discovery.common.entity.CustomizationEntity;
 import com.nepxion.discovery.common.entity.DiscoveryEntity;
+import com.nepxion.discovery.common.entity.RegionWeightEntity;
 import com.nepxion.discovery.common.entity.RouterEntity;
 import com.nepxion.discovery.common.entity.RuleEntity;
 import com.nepxion.discovery.common.entity.WeightEntity;
@@ -126,7 +127,7 @@ public class RouterEndpoint {
         String region = pluginAdapter.getRegion();
         String host = pluginAdapter.getHost();
         int port = pluginAdapter.getPort();
-        int weight = getWeight(serviceId, version);
+        int weight = getWeight(serviceId, version, region);
         Map<String, String> customMap = getCustomMap(serviceId);
         String contextPath = pluginAdapter.getContextPath();
 
@@ -164,7 +165,7 @@ public class RouterEndpoint {
             String region = metadata.get(DiscoveryConstant.REGION);
             String host = instance.getHost();
             int port = instance.getPort();
-            int weight = getWeight(routeServiceId, version);
+            int weight = getWeight(routeServiceId, version, region);
             Map<String, String> customMap = getCustomMap(serviceId);
             String contextPath = metadata.get(DiscoveryConstant.SPRING_APPLICATION_CONTEXT_PATH);
 
@@ -270,7 +271,7 @@ public class RouterEndpoint {
         return routerEntityList;
     }
 
-    private int getWeight(String providerServiceId, String providerVersion) {
+    private int getWeight(String providerServiceId, String providerVersion, String providerRegion) {
         RuleEntity ruleEntity = pluginAdapter.getRule();
         if (ruleEntity == null) {
             return -1;
@@ -286,23 +287,35 @@ public class RouterEndpoint {
             return -1;
         }
 
-        Map<String, List<WeightEntity>> weightEntityMap = weightFilterEntity.getWeightEntityMap();
-        if (MapUtils.isEmpty(weightEntityMap)) {
+        if (!weightFilterEntity.hasWeight()) {
             return -1;
         }
 
+        Map<String, List<WeightEntity>> weightEntityMap = weightFilterEntity.getWeightEntityMap();
+        RegionWeightEntity regionWeightEntity = weightFilterEntity.getRegionWeightEntity();
+
         String serviceId = pluginAdapter.getServiceId();
         // 取局部的权重配置
         int weight = getWeight(serviceId, providerServiceId, providerVersion, weightEntityMap);
+
         // 局部权重配置没找到，取全局的权重配置
         if (weight < 0) {
-            weight = getWeight(null, providerServiceId, providerVersion, weightEntityMap);
+            weight = getWeight(StringUtils.EMPTY, providerServiceId, providerVersion, weightEntityMap);
+        }
+
+        // 全局的权重配置没找到，取区域的权重配置
+        if (weight < 0) {
+            weight = getWeight(providerRegion, regionWeightEntity);
         }
 
         return weight;
     }
 
     private int getWeight(String consumerServiceId, String providerServiceId, String providerVersion, Map<String, List<WeightEntity>> weightEntityMap) {
+        if (MapUtils.isEmpty(weightEntityMap)) {
+            return -1;
+        }
+
         List<WeightEntity> weightEntityList = weightEntityMap.get(consumerServiceId);
         if (CollectionUtils.isEmpty(weightEntityList)) {
             return -1;
@@ -312,6 +325,10 @@ public class RouterEndpoint {
             String providerServiceName = weightEntity.getProviderServiceName();
             if (StringUtils.equalsIgnoreCase(providerServiceName, providerServiceId)) {
                 Map<String, Integer> weightMap = weightEntity.getWeightMap();
+                if (MapUtils.isEmpty(weightMap)) {
+                    return -1;
+                }
+
                 Integer weight = weightMap.get(providerVersion);
                 if (weight != null) {
                     return weight;
@@ -324,6 +341,28 @@ public class RouterEndpoint {
         return -1;
     }
 
+    private int getWeight(String providerRegion, RegionWeightEntity regionWeightEntity) {
+        if (StringUtils.isEmpty(providerRegion)) {
+            return -1;
+        }
+
+        if (regionWeightEntity == null) {
+            return -1;
+        }
+
+        Map<String, Integer> weightMap = regionWeightEntity.getWeightMap();
+        if (MapUtils.isEmpty(weightMap)) {
+            return -1;
+        }
+
+        Integer weight = weightMap.get(providerRegion);
+        if (weight != null) {
+            return weight;
+        } else {
+            return -1;
+        }
+    }
+
     private Map<String, String> getCustomMap(String serviceId) {
         RuleEntity ruleEntity = pluginAdapter.getRule();
         if (ruleEntity == null) {

discovery-plugin-config-center/src/main/java/com/nepxion/discovery/plugin/configcenter/constant/ConfigConstant.java

@@ -15,6 +15,7 @@ public class ConfigConstant {
     public static final String DISCOVERY_ELEMENT_NAME = "discovery";
     public static final String CUSTOMIZATION_ELEMENT_NAME = "customization";
     public static final String SERVICE_ELEMENT_NAME = "service";
+    public static final String REGION_ELEMENT_NAME = "region";
     public static final String BLACKLIST_ELEMENT_NAME = "blacklist";
     public static final String WHITELIST_ELEMENT_NAME = "whitelist";
     public static final String COUNT_ELEMENT_NAME = "count";

discovery-plugin-config-center/src/main/java/com/nepxion/discovery/plugin/configcenter/parser/xml/XmlConfigParser.java

@@ -30,6 +30,7 @@ import com.nepxion.discovery.common.entity.DiscoveryEntity;
 import com.nepxion.discovery.common.entity.FilterHolderEntity;
 import com.nepxion.discovery.common.entity.FilterType;
 import com.nepxion.discovery.common.entity.HostFilterEntity;
+import com.nepxion.discovery.common.entity.RegionWeightEntity;
 import com.nepxion.discovery.common.entity.RegisterEntity;
 import com.nepxion.discovery.common.entity.RuleEntity;
 import com.nepxion.discovery.common.entity.VersionEntity;
@@ -371,8 +372,10 @@ public class XmlConfigParser implements PluginConfigParser {
                     String consumerServiceName = null;
                     if (consumerServiceNameAttribute != null) {
                         consumerServiceName = consumerServiceNameAttribute.getData().toString().trim();
-                        weightEntity.setConsumerServiceName(consumerServiceName);
+                    } else {
+                        consumerServiceName = StringUtils.EMPTY;
                     }
+                    weightEntity.setConsumerServiceName(consumerServiceName);
 
                     Attribute providerServiceNameAttribute = childElement.attribute(ConfigConstant.PROVIDER_SERVICE_NAME_ATTRIBUTE_NAME);
                     if (providerServiceNameAttribute == null) {
@@ -407,6 +410,34 @@ public class XmlConfigParser implements PluginConfigParser {
                     }
 
                     weightEntityList.add(weightEntity);
+                } else if (StringUtils.equals(childElement.getName(), ConfigConstant.REGION_ELEMENT_NAME)) {
+                    RegionWeightEntity regionWeightEntity = weightFilterEntity.getRegionWeightEntity();
+                    if (regionWeightEntity != null) {
+                        throw new DiscoveryException("Allow only one element[" + ConfigConstant.REGION_ELEMENT_NAME + "] to be configed");
+                    }
+
+                    regionWeightEntity = new RegionWeightEntity();
+
+                    Attribute providerWeightValueAttribute = childElement.attribute(ConfigConstant.PROVIDER_WEIGHT_VALUE_ATTRIBUTE_NAME);
+                    if (providerWeightValueAttribute == null) {
+                        throw new DiscoveryException("Attribute[" + ConfigConstant.PROVIDER_WEIGHT_VALUE_ATTRIBUTE_NAME + "] in element[" + childElement.getName() + "] is missing");
+                    }
+                    String providerWeightValue = providerWeightValueAttribute.getData().toString().trim();
+                    Map<String, Integer> weightMap = new LinkedHashMap<String, Integer>();
+                    List<String> providerWeightValueList = parseList(providerWeightValue);
+                    for (String value : providerWeightValueList) {
+                        String[] valueArray = StringUtils.split(value, ConfigConstant.SEPARATE);
+                        String region = valueArray[0].trim();
+                        int weight = Integer.valueOf(valueArray[1].trim());
+                        if (weight < 0) {
+                            throw new DiscoveryException("Attribute[" + ConfigConstant.PROVIDER_WEIGHT_VALUE_ATTRIBUTE_NAME + "] in element[" + childElement.getName() + "] has weight value less than 0");
+                        }
+
+                        weightMap.put(region, weight);
+                    }
+                    regionWeightEntity.setWeightMap(weightMap);
+
+                    weightFilterEntity.setRegionWeightEntity(regionWeightEntity);
                 }
             }
         }

discovery-plugin-framework/src/main/java/com/nepxion/discovery/plugin/framework/adapter/AbstractPluginAdapter.java

@@ -151,4 +151,9 @@ public abstract class AbstractPluginAdapter implements PluginAdapter {
     public String getServerVersion(Server server) {
         return getServerMetadata(server).get(DiscoveryConstant.VERSION);
     }
+
+    @Override
+    public String getServerRegion(Server server) {
+        return getServerMetadata(server).get(DiscoveryConstant.REGION);
+    }
 }
\ No newline at end of file

discovery-plugin-framework/src/main/java/com/nepxion/discovery/plugin/framework/adapter/PluginAdapter.java

@@ -54,4 +54,6 @@ public interface PluginAdapter {
     Map<String, String> getServerMetadata(Server server);
 
     String getServerVersion(Server server);
+
+    String getServerRegion(Server server);
 }
\ No newline at end of file

discovery-plugin-framework/src/main/java/com/nepxion/discovery/plugin/framework/decorator/PredicateBasedRuleDecorator.java

@@ -10,14 +10,12 @@ package com.nepxion.discovery.plugin.framework.decorator;
  */
 
 import java.util.List;
-import java.util.Map;
 
 import javax.annotation.PostConstruct;
 
-import org.apache.commons.collections4.MapUtils;
 import org.springframework.beans.factory.annotation.Autowired;
 
-import com.nepxion.discovery.common.entity.WeightEntity;
+import com.nepxion.discovery.common.entity.WeightFilterEntity;
 import com.nepxion.discovery.plugin.framework.adapter.PluginAdapter;
 import com.nepxion.discovery.plugin.framework.loadbalance.WeightRandomLoadBalance;
 import com.netflix.loadbalancer.PredicateBasedRule;
@@ -37,15 +35,15 @@ public abstract class PredicateBasedRuleDecorator extends PredicateBasedRule {
 
     @Override
     public Server choose(Object key) {
-        Map<String, List<WeightEntity>> weightEntityMap = weightRandomLoadBalance.getWeightEntityMap();
-        if (MapUtils.isEmpty(weightEntityMap)) {
+        WeightFilterEntity weightFilterEntity = weightRandomLoadBalance.getWeightFilterEntity();
+        if (!weightFilterEntity.hasWeight()) {
             return super.choose(key);
         }
 
         List<Server> eligibleServers = getPredicate().getEligibleServers(getLoadBalancer().getAllServers(), key);
 
         try {
-            return weightRandomLoadBalance.choose(eligibleServers, weightEntityMap);
+            return weightRandomLoadBalance.choose(eligibleServers, weightFilterEntity);
         } catch (Exception e) {
             return super.choose(key);
         }

discovery-plugin-framework/src/main/java/com/nepxion/discovery/plugin/framework/decorator/ZoneAvoidanceRuleDecorator.java

@@ -10,14 +10,12 @@ package com.nepxion.discovery.plugin.framework.decorator;
  */
 
 import java.util.List;
-import java.util.Map;
 
 import javax.annotation.PostConstruct;
 
-import org.apache.commons.collections4.MapUtils;
 import org.springframework.beans.factory.annotation.Autowired;
 
-import com.nepxion.discovery.common.entity.WeightEntity;
+import com.nepxion.discovery.common.entity.WeightFilterEntity;
 import com.nepxion.discovery.plugin.framework.adapter.PluginAdapter;
 import com.nepxion.discovery.plugin.framework.loadbalance.WeightRandomLoadBalance;
 import com.netflix.loadbalancer.Server;
@@ -37,15 +35,15 @@ public class ZoneAvoidanceRuleDecorator extends ZoneAvoidanceRule {
 
     @Override
     public Server choose(Object key) {
-        Map<String, List<WeightEntity>> weightEntityMap = weightRandomLoadBalance.getWeightEntityMap();
-        if (MapUtils.isEmpty(weightEntityMap)) {
+        WeightFilterEntity weightFilterEntity = weightRandomLoadBalance.getWeightFilterEntity();
+        if (!weightFilterEntity.hasWeight()) {
             return super.choose(key);
         }
 
         List<Server> eligibleServers = getPredicate().getEligibleServers(getLoadBalancer().getAllServers(), key);
 
         try {
-            return weightRandomLoadBalance.choose(eligibleServers, weightEntityMap);
+            return weightRandomLoadBalance.choose(eligibleServers, weightFilterEntity);
         } catch (Exception e) {
             return super.choose(key);
         }

discovery-plugin-framework/src/main/java/com/nepxion/discovery/plugin/framework/loadbalance/WeightRandomLoadBalance.java

@@ -18,6 +18,7 @@ import org.apache.commons.collections4.MapUtils;
 import org.apache.commons.lang3.StringUtils;
 
 import com.nepxion.discovery.common.entity.DiscoveryEntity;
+import com.nepxion.discovery.common.entity.RegionWeightEntity;
 import com.nepxion.discovery.common.entity.RuleEntity;
 import com.nepxion.discovery.common.entity.WeightEntity;
 import com.nepxion.discovery.common.entity.WeightFilterEntity;
@@ -28,7 +29,7 @@ import com.netflix.loadbalancer.Server;
 public class WeightRandomLoadBalance {
     private PluginAdapter pluginAdapter;
 
-    public Map<String, List<WeightEntity>> getWeightEntityMap() {
+    public WeightFilterEntity getWeightFilterEntity() {
         RuleEntity ruleEntity = pluginAdapter.getRule();
         if (ruleEntity == null) {
             return null;
@@ -40,19 +41,11 @@ public class WeightRandomLoadBalance {
         }
 
         WeightFilterEntity weightFilterEntity = discoveryEntity.getWeightFilterEntity();
-        if (weightFilterEntity == null) {
-            return null;
-        }
 
-        Map<String, List<WeightEntity>> weightEntityMap = weightFilterEntity.getWeightEntityMap();
-        if (MapUtils.isEmpty(weightEntityMap)) {
-            return null;
+        return weightFilterEntity;
     }
 
-        return weightEntityMap;
-    }
-
-    public Server choose(List<Server> serverList, Map<String, List<WeightEntity>> weightEntityMap) {
+    public Server choose(List<Server> serverList, WeightFilterEntity weightFilterEntity) {
         if (CollectionUtils.isEmpty(serverList)) {
             return null;
         }
@@ -60,7 +53,7 @@ public class WeightRandomLoadBalance {
         int[] weights = new int[serverList.size()];
         for (int i = 0; i < serverList.size(); i++) {
             Server server = serverList.get(i);
-            int weight = getWeight(server, weightEntityMap);
+            int weight = getWeight(server, weightFilterEntity);
             if (weight > 0) {
                 weights[i] = weight;
             }
@@ -99,26 +92,40 @@ public class WeightRandomLoadBalance {
         return weightHolder[0][0];
     }
 
-    private int getWeight(Server server, Map<String, List<WeightEntity>> weightEntityMap) {
+    private int getWeight(Server server, WeightFilterEntity weightFilterEntity) {
+        Map<String, List<WeightEntity>> weightEntityMap = weightFilterEntity.getWeightEntityMap();
+        RegionWeightEntity regionWeightEntity = weightFilterEntity.getRegionWeightEntity();
+
         String providerServiceId = server.getMetaInfo().getAppName();
         String providerVersion = pluginAdapter.getServerVersion(server);
+        String providerRegion = pluginAdapter.getServerRegion(server);
 
         String serviceId = pluginAdapter.getServiceId();
         // 取局部的权重配置
         int weight = getWeight(serviceId, providerServiceId, providerVersion, weightEntityMap);
+
         // 局部权重配置没找到，取全局的权重配置
         if (weight < 0) {
-            weight = getWeight(null, providerServiceId, providerVersion, weightEntityMap);
+            weight = getWeight(StringUtils.EMPTY, providerServiceId, providerVersion, weightEntityMap);
         }
 
+        // 全局的权重配置没找到，取区域的权重配置
         if (weight < 0) {
-            throw new DiscoveryException("Weight isn't configed for serviceId=" + providerServiceId + ", version=" + providerVersion);
+            weight = getWeight(providerRegion, regionWeightEntity);
+        }
+
+        if (weight < 0) {
+            throw new DiscoveryException("Weight isn't configed for serviceId=" + providerServiceId);
         }
 
         return weight;
     }
 
     private int getWeight(String consumerServiceId, String providerServiceId, String providerVersion, Map<String, List<WeightEntity>> weightEntityMap) {
+        if (MapUtils.isEmpty(weightEntityMap)) {
+            return -1;
+        }
+
         List<WeightEntity> weightEntityList = weightEntityMap.get(consumerServiceId);
         if (CollectionUtils.isEmpty(weightEntityList)) {
             return -1;
@@ -128,6 +135,10 @@ public class WeightRandomLoadBalance {
             String providerServiceName = weightEntity.getProviderServiceName();
             if (StringUtils.equalsIgnoreCase(providerServiceName, providerServiceId)) {
                 Map<String, Integer> weightMap = weightEntity.getWeightMap();
+                if (MapUtils.isEmpty(weightMap)) {
+                    return -1;
+                }
+
                 Integer weight = weightMap.get(providerVersion);
                 if (weight != null) {
                     return weight;
@@ -140,6 +151,28 @@ public class WeightRandomLoadBalance {
         return -1;
     }
 
+    private int getWeight(String providerRegion, RegionWeightEntity regionWeightEntity) {
+        if (StringUtils.isEmpty(providerRegion)) {
+            return -1;
+        }
+
+        if (regionWeightEntity == null) {
+            return -1;
+        }
+
+        Map<String, Integer> weightMap = regionWeightEntity.getWeightMap();
+        if (MapUtils.isEmpty(weightMap)) {
+            return -1;
+        }
+
+        Integer weight = weightMap.get(providerRegion);
+        if (weight != null) {
+            return weight;
+        } else {
+            return -1;
+        }
+    }
+
     public void setPluginAdapter(PluginAdapter pluginAdapter) {
         this.pluginAdapter = pluginAdapter;
     }

discovery-springcloud-example-service/src/main/resources/rule.json

@@ -92,13 +92,32 @@
                             "1.1": 10
                         }
                     }
+                ], 
+                "": [
+                    {
+                        "consumerServiceName": "", 
+                        "providerServiceName": "discovery-springcloud-example-c", 
+                        "weightMap": {
+                            "1.0": 80, 
+                            "1.1": 20
+                        }
+                    }
                 ]
+            }, 
+            "regionWeightEntity": {
+                "weightMap": {
+                    "dev": 85, 
+                    "qa": 15
+                }
             }
         }
     }, 
     "customizationEntity": {
         "customizationMap": {
-            "discovery-springcloud-example-b": {
+            "discovery-springcloud-example-a": {
+                "database": "qa"
+            }, 
+            "discovery-springcloud-example-c": {
                 "database": "prod"
             }
         }

discovery-springcloud-example-service/src/main/resources/rule.xml

@@ -73,10 +73,13 @@
         <!-- 2. 局部配置，即指定consumer-service-name，专门为该消费端配置权重。全局配置，即不指定consumer-service-name，为所有消费端配置相同情形的权重。当局部配置和全局配置同时存在的时候，以局部配置优先 -->
         <!-- 3. 尽量为线上所有版本都赋予权重值 -->
         <weight>
+            <!-- 权重流量配置有如下三种方式，粒度由细到粗，优先级分别是由高到底，即先从第一种方式取权重流量值，取不到则到第二种方式取值，再取不到则到第二种方式取值，再取不到则忽略。使用者按照实际情况，选择一种即可 -->
             <!-- 表示消费端服务b访问提供端服务c的时候，提供端服务c的1.0版本提供90%的权重流量，1.1版本提供10%的权重流量 -->
             <service consumer-service-name="discovery-springcloud-example-b" provider-service-name="discovery-springcloud-example-c" provider-weight-value="1.0=90;1.1=10"/>
             <!-- 表示所有消费端服务访问提供端服务c的时候，提供端服务c的1.0版本提供80%的权重流量，1.1版本提供20%的权重流量 -->
             <service provider-service-name="discovery-springcloud-example-c" provider-weight-value="1.0=80;1.1=20"/>
+            <!-- 表示外界调用进来后，区域（region）为dev的服务提供85%的权重流量，区域（region）为qa的服务提供15%的权重流量 -->
+            <!-- <region provider-weight-value="dev=85;qa=15"/> -->
         </weight>
     </discovery>