init

Ocelot.Provider.Nacos/NacosClient/LoadBalance/WeightRoundRobinLBStrategy.cs

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+using Nacos;
+using System.Collections.Generic;
+using System.Linq;
+using Nacos.V2.Naming.Dtos;
+namespace Ocelot.Provider.Nacos.NacosClient
+{
+    public class WeightRoundRobinLBStrategy : ILBStrategy
+    {
+        public LBStrategyName Name => LBStrategyName.WeightRoundRobin;
+
+        private int _pos;
+
+        private static object obj = new object();
+
+        public Instance GetHost(List<Instance> list)
+        {
+            // aliyun sae, the instanceid returns empty string
+            // when the instanceid is empty, create a new one, but the group was missed.
+            list.ForEach(x => { x.InstanceId = string.IsNullOrWhiteSpace(x.InstanceId) ? $"{x.Ip}#{x.Port}#{x.ClusterName}#{x.ServiceName}" : x.InstanceId; });
+
+            var tmp = list.Select(x => new LbKv
+            {
+                InstanceId = x.InstanceId,
+                Weight = x.Weight
+            }).GroupBy(x => x.InstanceId).Select(x => new LbKv
+            {
+                InstanceId = x.Key,
+                Weight = x.Max(y => y.Weight)
+            }).ToList();
+
+            // <instanceid, weight>
+            var dic = tmp.ToDictionary(k => k.InstanceId, v => (int)v.Weight);
+
+            var srcInstanceIdList = dic.Keys.ToList();
+            var tagInstanceIdList = new List<string>();
+
+            foreach (var item in srcInstanceIdList)
+            {
+                dic.TryGetValue(item, out var weight);
+
+                for (int i = 0; i < weight; i++)
+                    tagInstanceIdList.Add(item);
+            }
+
+            var instanceId = string.Empty;
+
+            lock (obj)
+            {
+                if (_pos >= tagInstanceIdList.Count)
+                    _pos = 0;
+
+                instanceId = tagInstanceIdList[_pos];
+                _pos++;
+            }
+
+            var instance = list.FirstOrDefault(x => x.InstanceId.Equals(instanceId));
+
+            if (instance == null)
+            {
+                var arr = instanceId.Split("#");
+                var ip = arr[0];
+                int.TryParse(arr[1], out var port);
+                var cluster = arr[2];
+
+                instance = list.First(x => x.Ip.Equals(ip) && x.Port == port && x.ClusterName.Equals(cluster));
+            }
+
+            return instance;
+        }
+    }
+}