Test improved.

src/Squidex.Infrastructure/Log/LockingLogStore.cs

@@ -7,6 +7,7 @@
 
 using System;
 using System.IO;
+using System.Text;
 using System.Threading;
 using System.Threading.Tasks;
 using Orleans;
@@ -16,7 +17,8 @@ namespace Squidex.Infrastructure.Log
 {
     public sealed class LockingLogStore : ILogStore
     {
-        private static readonly TimeSpan LockWaitingTime = TimeSpan.FromMinutes(10);
+        private static readonly byte[] LockedText = Encoding.UTF8.GetBytes("Another process is currenty running, try it again later.");
+        private static readonly TimeSpan LockWaitingTime = TimeSpan.FromMinutes(1);
         private readonly ILogStore inner;
         private readonly ILockGrain lockGrain;
 
@@ -30,12 +32,17 @@ namespace Squidex.Infrastructure.Log
             lockGrain = grainFactory.GetGrain<ILockGrain>(SingleGrain.Id);
         }
 
-        public async Task ReadLogAsync(string key, DateTime from, DateTime to, Stream stream)
+        public Task ReadLogAsync(string key, DateTime from, DateTime to, Stream stream)
         {
-            string releaseToken = null;
+            return ReadLogAsync(key, from, to, stream, LockWaitingTime);
+        }
 
-            using (var cts = new CancellationTokenSource(LockWaitingTime))
+        public async Task ReadLogAsync(string key, DateTime from, DateTime to, Stream stream, TimeSpan lockTimeout)
+        {
+            using (var cts = new CancellationTokenSource(lockTimeout))
             {
+                string releaseToken = null;
+
                 while (!cts.IsCancellationRequested)
                 {
                     releaseToken = await lockGrain.AcquireLockAsync(key);
@@ -47,15 +54,22 @@ namespace Squidex.Infrastructure.Log
 
                     await Task.Delay(2000);
                 }
-            }
 
-            try
-            {
-                await inner.ReadLogAsync(key, from, to, stream);
-            }
-            finally
-            {
-                await lockGrain.ReleaseLockAsync(releaseToken);
+                if (!cts.IsCancellationRequested)
+                {
+                    try
+                    {
+                        await inner.ReadLogAsync(key, from, to, stream);
+                    }
+                    finally
+                    {
+                        await lockGrain.ReleaseLockAsync(releaseToken);
+                    }
+                }
+                else
+                {
+                    await stream.WriteAsync(LockedText, 0, LockedText.Length);
+                }
             }
         }
     }

tests/Squidex.Infrastructure.Tests/Log/LockingLogStoreTests.cs

@@ -56,5 +56,32 @@ namespace Squidex.Infrastructure.Log
             A.CallTo(() => inner.ReadLogAsync(key, dateFrom, dateTo, stream))
                 .MustHaveHappened();
         }
+
+        [Fact]
+        public async Task Should_write_default_message_if_lock_could_not_be_acquired()
+        {
+            var stream = new MemoryStream();
+
+            var dateFrom = DateTime.Today;
+            var dateTo = dateFrom.AddDays(2);
+
+            var key = "MyKey";
+
+            A.CallTo(() => lockGrain.AcquireLockAsync(key))
+                .Returns(Task.FromResult<string>(null));
+
+            await sut.ReadLogAsync(key, dateFrom, dateTo, stream, TimeSpan.FromSeconds(2));
+
+            A.CallTo(() => lockGrain.AcquireLockAsync(key))
+                .MustHaveHappened();
+
+            A.CallTo(() => lockGrain.ReleaseLockAsync(A<string>.Ignored))
+                .MustNotHaveHappened();
+
+            A.CallTo(() => inner.ReadLogAsync(A<string>.Ignored, A<DateTime>.Ignored, A<DateTime>.Ignored, A<Stream>.Ignored))
+                .MustNotHaveHappened();
+
+            Assert.True(stream.Length > 0);
+        }
     }
 }