Add tweaks to RedisSentinel API

Author: mythz

src/ServiceStack.Redis/RedisSentinel.cs

@@ -24,36 +24,43 @@ public class RedisSentinel : IRedisSentinel
         private int sentinelIndex = -1;
         private List<string> sentinels;
         private RedisSentinelWorker worker;
-        internal IRedisClientsManager redisManager;
         private static int MaxFailures = 5;
+
+        public IRedisClientsManager RedisManager { get; set; }
         public Action<IRedisClientsManager> OnFailover { get; set; }
-        public Action OnWorkerError { get; set; }
-        public Action<string,string> OnSentinelMessageReceived { get; set; }
+        public Action<Exception> OnWorkerError { get; set; }
+        public Action<string, string> OnSentinelMessageReceived { get; set; }
+
+        public RedisSentinel(string sentinelHost, string sentinelName)
+            : this(new[] { sentinelHost }, sentinelName) { }
 
         public RedisSentinel(IEnumerable<string> sentinelHosts, string sentinelName)
         {
             this.sentinels = sentinelHosts != null ? sentinelHosts.ToList() : null;
-            if (sentinelHosts == null || sentinels.Count == 0) 
+            if (sentinelHosts == null || sentinels.Count == 0)
                 throw new ArgumentException("sentinels must have at least one entry");
 
             this.sentinelName = sentinelName;
             this.RedisManagerFactory = new RedisManagerFactory();
         }
 
+        [Obsolete("Use Start()")]
+        public IRedisClientsManager Setup()
+        {
+            return Start();
+        }
+
         /// <summary>
-        /// Initialize channel and register client manager
+        /// Initialize Sentinel Subscription and Configure Redis ClientsManager
         /// </summary>
-        /// <param name="container"></param>
-        public IRedisClientsManager Setup()
+        public IRedisClientsManager Start()
         {
             GetValidSentinel();
 
-            if (this.redisManager == null)
-            {
+            if (this.RedisManager == null)
                 throw new ApplicationException("Unable to resolve sentinels!");
-            }
 
-            return this.redisManager;
+            return this.RedisManager;
         }
 
         public Func<string, string> HostFilter { get; set; }
@@ -75,23 +82,23 @@ private RedisSentinelWorker GetValidSentinel()
 
             RedisException lastEx = null;
 
-            while (this.redisManager == null && ShouldRetry())
+            while (this.RedisManager == null && ShouldRetry())
             {
                 try
                 {
                     this.worker = GetNextSentinel();
-                    this.redisManager = worker.GetClientManager();
+                    this.RedisManager = worker.GetClientManager();
                     this.worker.BeginListeningForConfigurationChanges();
                     return this.worker;
                 }
                 catch (RedisException ex)
                 {
+                    if (OnWorkerError != null)
+                        OnWorkerError(ex);
+
                     lastEx = ex;
                     if (this.worker != null)
-                    {
-                        this.worker.SentinelError -= Worker_SentinelError;
                         this.worker.Dispose();
-                    }
 
                     this.failures++;
                 }
@@ -115,13 +122,13 @@ private RedisSentinelWorker GetNextSentinel()
             sentinelIndex++;
 
             if (sentinelIndex >= sentinels.Count)
-            {
                 sentinelIndex = 0;
-            }
 
-            var sentinelWorker = new RedisSentinelWorker(this, sentinels[sentinelIndex], this.sentinelName);
+            var sentinelWorker = new RedisSentinelWorker(this, sentinels[sentinelIndex], this.sentinelName)
+            {
+                OnSentinelError = OnSentinelError
+            };
 
-            sentinelWorker.SentinelError += Worker_SentinelError;
             return sentinelWorker;
         }
 
@@ -130,21 +137,17 @@ private RedisSentinelWorker GetNextSentinel()
         /// </summary>
         /// <param name="sender"></param>
         /// <param name="e"></param>
-        private void Worker_SentinelError(object sender, EventArgs e)
+        private void OnSentinelError(Exception ex)
         {
-            var worker = sender as RedisSentinelWorker;
-
-            if (worker != null)
+            if (this.worker != null)
             {
-                Log.Info("Error on existing SentinelWorker, reconnecting...");
+                Log.Error("Error on existing SentinelWorker, reconnecting...");
+
                 if (OnWorkerError != null)
-                {
-                    OnWorkerError();
-                }
+                    OnWorkerError(ex);
 
                 // dispose the worker
-                worker.SentinelError -= Worker_SentinelError;
-                worker.Dispose();
+                this.worker.Dispose();
 
                 // get a new worker and start looking for more changes
                 this.worker = GetNextSentinel();
@@ -154,15 +157,13 @@ private void Worker_SentinelError(object sender, EventArgs e)
 
         public SentinelInfo FailoverToSentinelHosts()
         {
-            var worker = GetValidSentinel();
-            return worker.ConfigureRedisFromSentinel();            
+            return GetValidSentinel().ConfigureRedisFromSentinel();
         }
 
         public void Dispose()
         {
             if (worker != null)
             {
-                worker.SentinelError -= Worker_SentinelError;
                 worker.Dispose();
                 worker = null;
             }
@@ -178,7 +179,7 @@ public class SentinelInfo
     public SentinelInfo(List<string> redisMasters, List<string> redisSlaves)
     {
         RedisMasters = redisMasters != null ? redisMasters.ToArray() : new string[0];
-        RedisSlaves = redisSlaves != null ? RedisSlaves.ToArray() : new string[0];
+        RedisSlaves = redisSlaves != null ? redisSlaves.ToArray() : new string[0];
     }
 
     public override string ToString()

src/ServiceStack.Redis/RedisSentinelWorker.cs

@@ -19,12 +19,13 @@ internal class RedisSentinelWorker : IDisposable
         private string host;
         private IRedisClientsManager redisManager;
 
-        public event EventHandler SentinelError;
+        public Action<Exception> OnSentinelError;
 
         public RedisSentinelWorker(RedisSentinel redisSentinel, string host, string sentinelName)
         {
+
             this.redisSentinel = redisSentinel;
-            this.redisManager = redisSentinel.redisManager;
+            this.redisManager = redisSentinel.RedisManager;
             this.sentinelName = sentinelName;
 
             //Sentinel Servers doesn't support DB, reset to 0
@@ -33,7 +34,8 @@ public RedisSentinelWorker(RedisSentinel redisSentinel, string host, string sent
             this.sentinelSubscription = this.sentinelPubSubClient.CreateSubscription();
             this.sentinelSubscription.OnMessage = SentinelMessageReceived;
 
-            Log.Info("Set up Redis Sentinel on {0}".Fmt(host));
+            if (Log.IsDebugEnabled)
+                Log.Debug("Set up Redis Sentinel on {0}".Fmt(host));
         }
 
         private void SubscribeForChanges(object arg)
@@ -43,14 +45,13 @@ private void SubscribeForChanges(object arg)
                 // subscribe to all messages
                 this.sentinelSubscription.SubscribeToChannelsMatching("*");
             }
-            catch (Exception)
+            catch (Exception ex)
             {
-                Log.Error("Problem Subscribing to Redis Channel on {0}:{1}".Fmt(this.sentinelClient.Host, this.sentinelClient.Port));
-                // problem communicating to sentinel
-                if (SentinelError != null)
-                {
-                    SentinelError(this, EventArgs.Empty);
-                }
+                Log.Error("Error Subscribing to Redis Channel on {0}:{1}"
+                    .Fmt(this.sentinelClient.Host, this.sentinelClient.Port), ex);
+
+                if (OnSentinelError != null)
+                    OnSentinelError(ex);
             }
         }
 
@@ -61,6 +62,9 @@ private void SubscribeForChanges(object arg)
         /// <param name="message"></param>
         private void SentinelMessageReceived(string channel, string message)
         {
+            if (Log.IsDebugEnabled)
+                Log.Debug("Received '{0}' on channel '{1}' from Sentinel".Fmt(channel, message));
+
             // {+|-}sdown is the event for server coming up or down
             if (channel.ToLower().Contains("sdown"))
             {
@@ -70,9 +74,7 @@ private void SentinelMessageReceived(string channel, string message)
             }
 
             if (redisSentinel.OnSentinelMessageReceived != null)
-            {
                 redisSentinel.OnSentinelMessageReceived(channel, message);
-            }
         }
 
         /// <summary>