Akka.Persistence: automatically start snapshot store correctly (#2806)

* close #2770 - automatically start snapshot store correctly

* added copyright header

src/core/Akka.Persistence.Tests/Akka.Persistence.Tests.csproj

@@ -100,6 +100,7 @@
     <Compile Include="LoadPluginSpec.cs" />
     <Compile Include="MemoryEventAdapterSpec.cs" />
     <Compile Include="PerformanceSpec.cs" />
+    <Compile Include="PersistenceConfigAutoStartSpec.cs" />
     <Compile Include="PersistenceConfigSpec.cs" />
     <Compile Include="PersistenceSpec.cs" />
     <Compile Include="PersistentActorBoundedStashingSpec.cs" />

src/core/Akka.Persistence.Tests/PersistenceConfigAutoStartSpec.cs

@@ -0,0 +1,107 @@
+//-----------------------------------------------------------------------
+// <copyright file="PersistenceConfigAutoStartSpec.cs" company="Akka.NET Project">
+//     Copyright (C) 2009-2016 Lightbend Inc. <http://www.lightbend.com>
+//     Copyright (C) 2013-2016 Akka.NET project <https://github.com/akkadotnet/akka.net>
+// </copyright>
+//-----------------------------------------------------------------------
+
+using Akka.Actor;
+using Akka.Configuration;
+using Akka.Persistence.Journal;
+using Akka.Persistence.Snapshot;
+using Akka.TestKit;
+using Xunit;
+using Xunit.Abstractions;
+
+namespace Akka.Persistence.Tests
+{
+    public class PersistenceConfigAutoStartSpec : AkkaSpec
+    {
+        #region internal classes
+
+        private sealed class TestRequest
+        {
+            public static readonly TestRequest Instance = new TestRequest();
+
+            private TestRequest()
+            {
+            }
+        }
+
+        public class TestJournal : MemoryJournal
+        {
+            private readonly string _testValue;
+
+            public TestJournal(Config config)
+            {
+                _testValue = config.GetString("test-value");
+            }
+
+            protected override bool AroundReceive(Receive receive, object message)
+            {
+                if (message is TestRequest)
+                {
+                    Sender.Tell(_testValue);
+                    return true;
+                }
+                else return base.AroundReceive(receive, message);
+            }
+        }
+
+        public class TestSnapshotStore : LocalSnapshotStore
+        {
+            private readonly string _testValue;
+
+            public TestSnapshotStore(Config config)
+            {
+                _testValue = config.GetString("test-value");
+            }
+
+            protected override bool AroundReceive(Receive receive, object message)
+            {
+                if (message is TestRequest)
+                {
+                    Sender.Tell(_testValue);
+                    return true;
+                }
+                else return base.AroundReceive(receive, message);
+            }
+        }
+
+        #endregion
+
+        private static readonly Config AutoStartConfig = ConfigurationFactory.ParseString(@"
+            akka.loglevel = INFO
+            akka.persistence.journal {
+                test {
+                    class = ""Akka.Persistence.Tests.PersistenceConfigAutoStartSpec+TestJournal, Akka.Persistence.Tests""
+                    plugin-dispatcher = ""akka.actor.default-dispatcher""
+                    test-value = ""A""
+                }
+                auto-start-journals = [akka.persistence.journal.test]
+            }
+            akka.persistence.snapshot-store {
+                test {
+                    class = ""Akka.Persistence.Tests.PersistenceConfigAutoStartSpec+TestSnapshotStore, Akka.Persistence.Tests""
+                    plugin-dispatcher = ""akka.actor.default-dispatcher""
+                    test-value = ""C""
+                }
+                auto-start-snapshot-stores = [akka.persistence.snapshot-store.test]
+            }
+        ");
+
+        public PersistenceConfigAutoStartSpec(ITestOutputHelper output = null) : base(AutoStartConfig, output)
+        {
+        }
+
+        [Fact]
+        public void Persistence_should_auto_start_journal_and_snapshotstore_when_specified()
+        {
+            EventFilter.Info(message: "Auto-starting journal plugin `akka.persistence.journal.test`")
+                .And.Info(message: "Auto-starting snapshot store `akka.persistence.snapshot-store.test`").Expect(2, () =>
+            {
+                var persistence = Persistence.Instance.Apply(Sys);
+            });
+        }
+    }
+}

src/core/Akka.Persistence/Persistence.cs

@@ -34,7 +34,7 @@ public PluginHolder(IActorRef @ref, EventAdapters adapters, Config config)
     }
 
     /// <summary>
-    /// TBD
+    /// Launches the Akka.Persistence runtime
     /// </summary>
     public class PersistenceExtension : IExtension
     {
@@ -55,12 +55,15 @@ public class PersistenceExtension : IExtension
         private const string SnapshotStoreFallbackConfigPath = "akka.persistence.snapshot-store-plugin-fallback";
 
         /// <summary>
-        /// TBD
+        /// Creates a new Akka.Persistence extension.
         /// </summary>
-        /// <param name="system">TBD</param>
-        /// <exception cref="NullReferenceException">TBD
+        /// <param name="system">The ActorSystem that will be using Akka.Persistence</param>
+        /// <exception cref="NullReferenceException">
         /// This exception is thrown when the default journal plugin, <c>journal.plugin</c> is not configured.
         /// </exception>
+        /// <remarks>
+        /// DO NOT CALL DIRECTLY. Will be instantiated automatically be Akka.Persistence actors.
+        /// </remarks>
         public PersistenceExtension(ExtendedActorSystem system)
         {
             _system = system;
@@ -106,7 +109,7 @@ public PersistenceExtension(ExtendedActorSystem system)
                 JournalFor(id);
             });
 
-            _config.GetStringList("journal.auto-start-snapshot-stores").ForEach(id =>
+            _config.GetStringList("snapshot-store.auto-start-snapshot-stores").ForEach(id =>
             {
                 if (_log.IsInfoEnabled)
                     _log.Info("Auto-starting snapshot store `{0}`", id);
@@ -120,7 +123,7 @@ public PersistenceExtension(ExtendedActorSystem system)
         public IStashOverflowStrategy DefaultInternalStashOverflowStrategy => _defaultInternalStashOverflowStrategy.Value;
 
         /// <summary>
-        /// TBD
+        /// The Akka.Persistence settings for the journal and snapshot store
         /// </summary>
         public PersistenceSettings Settings { get; }