add a new cluster kind for redis-cluster-proxy; in most ways it is similar to twemproxy

src/StackExchange.Redis/CommandMap.cs

@@ -21,7 +21,7 @@ internal CommandMap(CommandBytes[] map)
         public static CommandMap Default { get; } = CreateImpl(null, null);
 
         /// <summary>
-        /// The commands available to <a href="twemproxy">https://github.com/twitter/twemproxy</a>
+        /// The commands available to <a href="https://github.com/twitter/twemproxy/">twemproxy</a>
         /// </summary>
         /// <remarks>https://github.com/twitter/twemproxy/blob/master/notes/redis.md</remarks>
         public static CommandMap Twemproxy { get; } = CreateImpl(null, exclusions: new HashSet<RedisCommand>
@@ -53,6 +53,49 @@ internal CommandMap(CommandBytes[] map)
             RedisCommand.SHUTDOWN, RedisCommand.SLAVEOF, RedisCommand.SLOWLOG, RedisCommand.SYNC, RedisCommand.TIME
         });
 
+        /// <summary>
+        /// The commands available to <a href="https://github.com/RedisLabs/redis-cluster-proxy/">redis-cluster-proxy</a>
+        /// </summary>
+        /// <remarks>https://github.com/RedisLabs/redis-cluster-proxy/</remarks>
+        public static CommandMap RedisClusterProxy { get; } = CreateImpl(null, exclusions: new HashSet<RedisCommand>
+        {
+            // via "proxy command unsupported"
+            // RedisCommand.ACL,
+            RedisCommand.ASKING,
+            RedisCommand.CLIENT,
+            RedisCommand.CLUSTER,
+            RedisCommand.CONFIG,
+            RedisCommand.DEBUG,
+            // RedisCommand.HELLO,
+            RedisCommand.INFO,
+            RedisCommand.LATENCY,
+            RedisCommand.MEMORY,
+            RedisCommand.MIGRATE,
+            // RedisCommand.MODULE,
+            RedisCommand.MONITOR,
+            // RedisCommand.PFDEBUG,
+            // RedisCommand.PFSELFTEST,
+            RedisCommand.PSUBSCRIBE,
+            // RedisCommand.PSYNC,
+            RedisCommand.PUBLISH,
+            RedisCommand.PUBSUB,
+            RedisCommand.PUNSUBSCRIBE,
+            RedisCommand.READONLY,
+            RedisCommand.READWRITE,
+            // RedisCommand.REPLCONF,
+            // RedisCommand.REPLICAOF,
+            // RedisCommand.ROLE,
+            RedisCommand.SCRIPT,
+            RedisCommand.SHUTDOWN,
+            RedisCommand.SLAVEOF,
+            RedisCommand.SLOWLOG,
+            RedisCommand.SUBSCRIBE,
+            RedisCommand.SYNC,
+            RedisCommand.TIME,
+            RedisCommand.UNSUBSCRIBE,
+            // RedisCommand.WAIT,
+        });
+
         /// <summary>
         /// The commands available to <a href="ssdb">http://www.ideawu.com/ssdb/</a>
         /// </summary>

src/StackExchange.Redis/ConfigurationOptions.cs

@@ -251,6 +251,8 @@ public CommandMap CommandMap
                 {
                     case Proxy.Twemproxy:
                         return CommandMap.Twemproxy;
+                    case Proxy.RedisClusterProxy:
+                        return CommandMap.RedisClusterProxy;
                     default:
                         return CommandMap.Default;
                 }
@@ -482,7 +484,14 @@ public ConfigurationOptions Clone()
         /// </summary>
         public void SetDefaultPorts()
         {
-            EndPoints.SetDefaultPorts(Ssl ? 6380 : 6379);
+            if (Proxy == Proxy.RedisClusterProxy && !Ssl)
+            {
+                EndPoints.SetDefaultPorts(7777); // default port for redis-cluster-proxy
+            }
+            else
+            {
+                EndPoints.SetDefaultPorts(Ssl ? 6380 : 6379);
+            }
         }
 
         /// <summary>

src/StackExchange.Redis/ConnectionMultiplexer.cs

@@ -1248,7 +1248,12 @@ internal long LastHeartbeatSecondsAgo
         /// <param name="asyncState">The async state object to pass to the created <see cref="RedisSubscriber"/>.</param>
         public ISubscriber GetSubscriber(object asyncState = null)
         {
-            if (RawConfig.Proxy == Proxy.Twemproxy) throw new NotSupportedException("The pub/sub API is not available via twemproxy");
+            switch (RawConfig.Proxy)
+            {
+                case Proxy.Twemproxy:
+                case Proxy.RedisClusterProxy:
+                    throw new NotSupportedException($"The pub/sub API is not available via {RawConfig.Proxy}");
+            }
             return new RedisSubscriber(this, asyncState);
         }
 
@@ -1263,7 +1268,15 @@ public IDatabase GetDatabase(int db = -1, object asyncState = null)
                 db = RawConfig.DefaultDatabase ?? 0;
 
             if (db < 0) throw new ArgumentOutOfRangeException(nameof(db));
-            if (db != 0 && RawConfig.Proxy == Proxy.Twemproxy) throw new NotSupportedException("Twemproxy only supports database 0");
+            if (db != 0)
+            {
+                switch (RawConfig.Proxy)
+                {
+                    case Proxy.Twemproxy:
+                    case Proxy.RedisClusterProxy:
+                        throw new NotSupportedException($"{RawConfig.Proxy} only supports database 0");
+                }
+            }
 
             // if there's no async-state, and the DB is suitable, we can hand out a re-used instance
             return (asyncState == null && db <= MaxCachedDatabaseInstance)
@@ -1318,7 +1331,12 @@ public IDatabase GetDatabase(int db = -1, object asyncState = null)
         public IServer GetServer(EndPoint endpoint, object asyncState = null)
         {
             if (endpoint == null) throw new ArgumentNullException(nameof(endpoint));
-            if (RawConfig.Proxy == Proxy.Twemproxy) throw new NotSupportedException("The server API is not available via twemproxy");
+            switch (RawConfig.Proxy)
+            {
+                case Proxy.RedisClusterProxy:
+                case Proxy.Twemproxy:
+                    throw new NotSupportedException($"The server API is not available via {RawConfig.Proxy}");
+            }
             var server = (ServerEndPoint)servers[endpoint];
             if (server == null) throw new ArgumentException("The specified endpoint is not defined", nameof(endpoint));
             return new RedisServer(this, server, asyncState);
@@ -1634,6 +1652,7 @@ internal async Task<bool> ReconfigureAsync(bool first, bool reconfigureAll, LogP
                                     {
                                         case ServerType.Twemproxy:
                                         case ServerType.Standalone:
+                                        case ServerType.RedisClusterProxy:
                                             standaloneCount++;
                                             break;
                                         case ServerType.Sentinel:
@@ -1657,6 +1676,7 @@ internal async Task<bool> ReconfigureAsync(bool first, bool reconfigureAll, LogP
                                     switch (server.ServerType)
                                     {
                                         case ServerType.Twemproxy:
+                                        case ServerType.RedisClusterProxy:
                                         case ServerType.Sentinel:
                                         case ServerType.Standalone:
                                         case ServerType.Cluster:
@@ -1701,17 +1721,24 @@ internal async Task<bool> ReconfigureAsync(bool first, bool reconfigureAll, LogP
                     if (clusterCount == 0)
                     {
                         // set the serverSelectionStrategy
-                        if (RawConfig.Proxy == Proxy.Twemproxy)
-                        {
-                            ServerSelectionStrategy.ServerType = ServerType.Twemproxy;
-                        }
-                        else if (standaloneCount == 0 && sentinelCount > 0)
-                        {
-                            ServerSelectionStrategy.ServerType = ServerType.Sentinel;
-                        }
-                        else
+                        switch (RawConfig.Proxy)
                         {
-                            ServerSelectionStrategy.ServerType = ServerType.Standalone;
+                            case Proxy.Twemproxy:
+                                ServerSelectionStrategy.ServerType = ServerType.Twemproxy;
+                                break;
+                            case Proxy.RedisClusterProxy:
+                                ServerSelectionStrategy.ServerType = ServerType.RedisClusterProxy;
+                                break;
+                            default:
+                                if (standaloneCount == 0 && sentinelCount > 0)
+                                {
+                                    ServerSelectionStrategy.ServerType = ServerType.Sentinel;
+                                }
+                                else
+                                {
+                                    ServerSelectionStrategy.ServerType = ServerType.Standalone;
+                                }
+                                break;
                         }
                         var preferred = await NominatePreferredMaster(log, servers, useTieBreakers, tieBreakers, masters).ObserveErrors().ForAwait();
                         foreach (var master in masters)

src/StackExchange.Redis/Enums/Proxy.cs

@@ -12,6 +12,10 @@ public enum Proxy
         /// <summary>
         /// Communication via <a href="https://github.com/twitter/twemproxy">twemproxy</a>
         /// </summary>
-        Twemproxy
+        Twemproxy,
+        /// <summary>
+        /// Communication via <a href="https://github.com/RedisLabs/redis-cluster-proxy">redis-cluster-proxy</a>
+        /// </summary>
+        RedisClusterProxy,
     }
 }

src/StackExchange.Redis/Enums/ServerType.cs

@@ -20,6 +20,10 @@ public enum ServerType
         /// <summary>
         /// Distributed redis installation via <a href="https://github.com/twitter/twemproxy">twemproxy</a>
         /// </summary>
-        Twemproxy
+        Twemproxy,
+        /// <summary>
+        /// Distributed redis installation via <a href="https://github.com/RedisLabs/redis-cluster-proxy">redis-cluster-proxy</a>
+        /// </summary>
+        RedisClusterProxy,
     }
 }

src/StackExchange.Redis/ServerEndPoint.cs

@@ -57,11 +57,19 @@ public ServerEndPoint(ConnectionMultiplexer multiplexer, EndPoint endpoint)
             writeEverySeconds = config.KeepAlive > 0 ? config.KeepAlive : 60;
             serverType = ServerType.Standalone;
 
-            // overrides for twemproxy
-            if (multiplexer.RawConfig.Proxy == Proxy.Twemproxy)
+            // overrides for twemproxy etc
+            switch (multiplexer.RawConfig.Proxy)
             {
-                databases = 1;
-                serverType = ServerType.Twemproxy;
+                case Proxy.Twemproxy:
+                    databases = 1;
+                    serverType = ServerType.Twemproxy;
+                    break;
+                case Proxy.RedisClusterProxy:
+                    databases = 1;
+                    serverType = ServerType.RedisClusterProxy;
+                    if (version < RedisFeatures.v3_0_0) // cluster is at least 3.0
+                        version = RedisFeatures.v3_0_0;
+                    break;
             }
         }
 
@@ -254,11 +262,13 @@ internal void AddScript(string script, byte[] hash)
 
         internal void AutoConfigure(PhysicalConnection connection)
         {
-            if (serverType == ServerType.Twemproxy)
+            switch (serverType)
             {
-                // don't try to detect configuration; all the config commands are disabled, and
-                // the fallback master/slave detection won't help
-                return;
+                case ServerType.Twemproxy:
+                case ServerType.RedisClusterProxy:
+                    // don't try to detect configuration; all the config commands are disabled, and
+                    // the fallback master/slave detection won't help
+                    return;
             }
 
             var commandMap = Multiplexer.CommandMap;

tests/StackExchange.Redis.Tests/RedisClusterProxyTests.cs

+using System;
+using Xunit;
+using Xunit.Abstractions;
+
+namespace StackExchange.Redis.Tests
+{
+    public class RedisClusterProxyTests : TestBase
+    {
+        public RedisClusterProxyTests(ITestOutputHelper output) : base(output) { }
+
+        protected override string GetConfiguration() => "127.0.0.1,proxy=RedisClusterProxy,version=5.0";
+
+        [Fact(Skip = "No CI build for this yet")]
+        public void CanConnectToClusterProxy()
+        {
+            using (var conn = Create())
+            {
+                var expected = Guid.NewGuid().ToString();
+                var db = conn.GetDatabase();
+                RedisKey key = Me();
+                db.StringSet(key, expected);
+                var actual = (string)db.StringGet(key);
+                Assert.Equal(expected, actual);
+
+                // check it knows that we're dealing with a cluster
+                var ex = Assert.Throws<NotSupportedException>(() => conn.GetServer("abc"));
+                Assert.Equal("The server API is not available via RedisClusterProxy", ex.Message);
+
+                ex = Assert.Throws<NotSupportedException>(() => conn.GetSubscriber("abc"));
+                Assert.Equal("The pub/sub API is not available via RedisClusterProxy", ex.Message);
+
+                // test a script
+                const string LUA_SCRIPT = "return redis.call('info')";
+                var name = (string)db.ScriptEvaluate(LUA_SCRIPT);
+                Log($"client: {name}");
+                // run it twice to check we didn't rely on script hashing (SCRIPT is disabled)
+                _ = db.ScriptEvaluate(LUA_SCRIPT);
+            }
+        }
+    }
+}