Test and docs about configuring log levels with sagas. Closes GH-1824

docs/guide/durability/sagas.md

@@ -504,6 +504,13 @@ public void Handle(OrderTimeout timeout, ILogger<Order> logger)
 <sup><a href='https://github.com/JasperFx/wolverine/blob/main/src/Samples/OrderSagaSample/OrderSaga.cs#L51-L63' title='Snippet source file'>snippet source</a> | <a href='#snippet-sample_handling_a_timeout_message' title='Start of snippet'>anchor</a></sup>
 <!-- endSnippet -->
 
+## Saga Concurrency
+
+Both the Marten and EF Core backed saga support has built in support for optimistic concurrency checks on persisting
+a saga after handling a command. See [Dealing with Concurrency](/tutorials/concurrency) and especially the 
+[partitioned sequential messaging](/tutorials/concurrency) and its option for "inferred" message grouping to maybe completely
+side step concurrency issues with saga message handling. 
+
 ## Lightweight Saga Storage <Badge type="tip" text="3.0" />
 
 The Wolverine integration with either Sql Server or PostgreSQL comes with a lightweight saga storage mechanism
@@ -543,3 +550,20 @@ using var host = await Host.CreateDefaultBuilder()
 
 Note that this manual registration is not necessary at development time or if you're content to just let Wolverine
 handle database migrations at runtime.
+
+## Overriding Logging
+
+We recently had a question about how to turn down logging levels for `Saga` message processing when the log
+output was getting too verbose. `Saga` types are officially message handlers to the Wolverine internals, so you can 
+still use the `public static void Configure(HandlerChain)` mechanism for one off configurations to every message handler
+method on the `Saga` like this:
+
+snippet: sample_overriding_logging_on_saga
+
+Or if you wanted to just do it globally, something like this approach:
+
+snippet: sample_turn_down_logging_for_sagas
+
+and register that policy something like this:
+
+snippet: sample_configuring_chain_policy_on_sagas

src/Persistence/MartenTests/Saga/RevisionedSaga.cs

@@ -1,12 +1,17 @@
 using IntegrationTests;
 using JasperFx.CodeGeneration;
 using JasperFx.Core;
+using JasperFx.Core.Reflection;
 using Marten;
 using Marten.Metadata;
 using Microsoft.Extensions.Hosting;
 using JasperFx.Resources;
+using Microsoft.Extensions.Logging;
+using Shouldly;
 using Wolverine;
 using Wolverine.Marten;
+using Wolverine.Runtime;
+using Wolverine.Runtime.Handlers;
 using Wolverine.Tracking;
 
 namespace MartenTests.Saga;
@@ -31,6 +36,16 @@ public async Task InitializeAsync()
             }).StartAsync();
     }
 
+    [Fact]
+    public void can_override_the_log_level()
+    {
+        var runtime = theHost.GetRuntime();
+        runtime.As<IExecutorFactory>().BuildFor(typeof(StartNewRevisionedSaga));
+        var chain = runtime.Handlers.ChainFor<StartNewRevisionedSaga>();
+        chain.SuccessLogLevel.ShouldBe(LogLevel.None);
+        chain.ProcessingLogLevel.ShouldBe(LogLevel.None);
+    }
+
     [Fact]
     public async Task execute_using_update_revision()
     {
@@ -62,8 +77,20 @@ public async Task DisposeAsync()
     }
 }
 
+#region sample_overriding_logging_on_saga
+
 public class RevisionedSaga : Wolverine.Saga
 {
+    // This works just the same as on any other message handler
+    // type
+    public static void Configure(HandlerChain chain)
+    {
+        chain.ProcessingLogLevel = LogLevel.None;
+        chain.SuccessLogLevel = LogLevel.None;
+    }
+
+    #endregion
+
     public static TaskCompletionSource InSlowMessage = new TaskCompletionSource();
 
     public static RevisionedSaga Start(StartNewRevisionedSaga command) => new RevisionedSaga { Id = command.Id };

src/Persistence/PersistenceTests/Samples/SagaChainPolicies.cs

@@ -0,0 +1,41 @@
+using JasperFx;
+using JasperFx.CodeGeneration;
+using Microsoft.Extensions.Hosting;
+using Microsoft.Extensions.Logging;
+using Wolverine;
+using Wolverine.Configuration;
+using Wolverine.Persistence.Sagas;
+
+namespace PersistenceTests.Samples;
+
+public class SagaChainPolicies
+{
+    public static async Task configure()
+    {
+        #region sample_configuring_chain_policy_on_sagas
+
+        using var host = await Host.CreateDefaultBuilder()
+            .UseWolverine(opts =>
+            {
+                opts.Policies.Add<TurnDownLoggingOnSagas>();
+            }).StartAsync();
+
+        #endregion
+    }
+}
+
+#region sample_turn_down_logging_for_sagas
+
+public class TurnDownLoggingOnSagas : IChainPolicy
+{
+    public void Apply(IReadOnlyList<IChain> chains, GenerationRules rules, IServiceContainer container)
+    {
+        foreach (var sagaChain in chains.OfType<SagaChain>())
+        {
+            sagaChain.ProcessingLogLevel = LogLevel.None;
+            sagaChain.SuccessLogLevel = LogLevel.None;
+        }
+    }
+}
+
+#endregion