From 9cdff8c318159624eb3f0a24ad03665170aeaba7 Mon Sep 17 00:00:00 2001
From: Sipke Schoorstra <sipkeschoorstra@outlook.com>
Date: Wed, 20 May 2026 23:39:35 +0200
Subject: [PATCH] Handle missing distributed lock provider in readiness check

---
 .../ElsaDistributedLockHealthCheck.cs         | 12 +++++++++-
 .../ElsaDistributedLockHealthCheckTests.cs    | 24 ++++++++++++++++++-
 2 files changed, 34 insertions(+), 2 deletions(-)

diff --git a/src/modules/Elsa.Workflows.Runtime/HealthChecks/ElsaDistributedLockHealthCheck.cs b/src/modules/Elsa.Workflows.Runtime/HealthChecks/ElsaDistributedLockHealthCheck.cs
index 756089f3c..c585ce685 100644
--- a/src/modules/Elsa.Workflows.Runtime/HealthChecks/ElsaDistributedLockHealthCheck.cs
+++ b/src/modules/Elsa.Workflows.Runtime/HealthChecks/ElsaDistributedLockHealthCheck.cs
@@ -1,5 +1,6 @@
 using Elsa.Common;
 using Medallion.Threading;
+using Microsoft.Extensions.DependencyInjection;
 using Microsoft.Extensions.Diagnostics.HealthChecks;
 
 namespace Elsa.Workflows.Runtime.HealthChecks;
@@ -7,7 +8,7 @@ namespace Elsa.Workflows.Runtime.HealthChecks;
 /// <summary>
 /// Verifies that the configured distributed lock provider can acquire and release a probe lock.
 /// </summary>
-public class ElsaDistributedLockHealthCheck(IDistributedLockProvider distributedLockProvider) : IHealthCheck
+public class ElsaDistributedLockHealthCheck(IServiceProvider serviceProvider) : IHealthCheck
 {
     private static readonly string LockName = $"elsa-health-check-{Environment.MachineName}-{Guid.NewGuid():N}";
     private static readonly TimeSpan LockAcquisitionTimeout = TimeSpan.FromSeconds(1);
@@ -17,6 +18,15 @@ public class ElsaDistributedLockHealthCheck(IDistributedLockProvider distributed
     {
         try
         {
+            var distributedLockProvider = serviceProvider.GetService<IDistributedLockProvider>();
+            if (distributedLockProvider == null)
+            {
+                return HealthCheckResult.Degraded("Elsa distributed lock provider is not registered.", data: new Dictionary<string, object>
+                {
+                    ["category"] = "distributed-locks"
+                });
+            }
+
             await using var handle = await distributedLockProvider.TryAcquireLockAsync(LockName, LockAcquisitionTimeout, cancellationToken);
             if (handle == null)
             {
diff --git a/test/unit/Elsa.Workflows.Runtime.UnitTests/HealthChecks/ElsaDistributedLockHealthCheckTests.cs b/test/unit/Elsa.Workflows.Runtime.UnitTests/HealthChecks/ElsaDistributedLockHealthCheckTests.cs
index 297eaa90a..bfebf682e 100644
--- a/test/unit/Elsa.Workflows.Runtime.UnitTests/HealthChecks/ElsaDistributedLockHealthCheckTests.cs
+++ b/test/unit/Elsa.Workflows.Runtime.UnitTests/HealthChecks/ElsaDistributedLockHealthCheckTests.cs
@@ -1,5 +1,6 @@
 using Elsa.Workflows.Runtime.HealthChecks;
 using Medallion.Threading;
+using Microsoft.Extensions.DependencyInjection;
 using Microsoft.Extensions.Diagnostics.HealthChecks;
 using NSubstitute;
 
@@ -17,7 +18,7 @@ public class ElsaDistributedLockHealthCheckTests
         _distributedLockProvider.CreateLock(Arg.Any<string>()).Returns(_distributedLock);
         _distributedLock.TryAcquireAsync(Arg.Any<TimeSpan>(), Arg.Any<CancellationToken>())
             .Returns(new ValueTask<IDistributedSynchronizationHandle?>(Substitute.For<IDistributedSynchronizationHandle>()));
-        _sut = new ElsaDistributedLockHealthCheck(_distributedLockProvider);
+        _sut = new ElsaDistributedLockHealthCheck(CreateServiceProvider(_distributedLockProvider));
     }
 
     [Fact]
@@ -53,4 +54,25 @@ public class ElsaDistributedLockHealthCheckTests
         Assert.Equal(HealthStatus.Unhealthy, result.Status);
         Assert.Equal("distributed-locks", result.Data["category"]);
     }
+
+    [Fact]
+    public async Task ReturnsDegradedWhenProviderIsNotRegistered()
+    {
+        var sut = new ElsaDistributedLockHealthCheck(CreateServiceProvider());
+
+        var result = await sut.CheckHealthAsync(new HealthCheckContext());
+
+        Assert.Equal(HealthStatus.Degraded, result.Status);
+        Assert.Equal("distributed-locks", result.Data["category"]);
+    }
+
+    private static IServiceProvider CreateServiceProvider(IDistributedLockProvider? distributedLockProvider = null)
+    {
+        var services = new ServiceCollection();
+
+        if (distributedLockProvider != null)
+            services.AddSingleton(distributedLockProvider);
+
+        return services.BuildServiceProvider();
+    }
 }