handle Exception during Execution

Author: danielklecha

PipelineBlocks/Models/BlockResult.cs

@@ -5,32 +5,34 @@ public class BlockResult
     public string? Key { get; }
     public object? Data { get; }
     public string? Message { get; }
+    public Exception? Exception { get; set; }
     public BlockResultType ResultType { get; }
 
-    internal BlockResult(object? data, string? key, string? message, BlockResultType resultType)
+    internal BlockResult(object? data, string? key, string? message, BlockResultType resultType, Exception? exception)
     {
         Data = data;
         Key = key;
         Message = message;
         ResultType = resultType;
+        Exception = exception;
     }
 
-    public static BlockResult Completed(string? message = null) => new(default, null, message, BlockResultType.Completed);
-    public static BlockResult Error(string? message = null) => new(default, null, message, BlockResultType.Error);
-    public static BlockResult<T> Exit<T>(T? data = default) => new(data, null, null, BlockResultType.Exit);
-    public static BlockResult<T> Forward<T>(T? data = default) => new(data, null, null, BlockResultType.Forward);
-    public static BlockResult<T> Execute<T>(T? data = default) => new(data, null, null, BlockResultType.Execute);
+    public static BlockResult Completed(string? message = null) => new(default, null, message, BlockResultType.Completed, null);
+    public static BlockResult Error(string? message = null, Exception? exception = null) => new(default, null, message, BlockResultType.Error, exception);
+    public static BlockResult<T> Exit<T>(T? data = default) => new(data, null, null, BlockResultType.Exit, null);
+    public static BlockResult<T> Forward<T>(T? data = default) => new(data, null, null, BlockResultType.Forward, null);
+    public static BlockResult<T> Execute<T>(T? data = default) => new(data, null, null, BlockResultType.Execute, null);
 }
 
 public class BlockResult<T> : BlockResult
 {
     public new T? Data { get; }
 
-    internal BlockResult(T? data, string? key, string? message, BlockResultType resultType) : base(data, key, message, resultType) => Data = data;
+    internal BlockResult(T? data, string? key, string? message, BlockResultType resultType, Exception? exception) : base(data, key, message, resultType, exception) => Data = data;
 
-    public static new BlockResult<T> Completed(string? message = null) => new(default, null, message, BlockResultType.Completed);
-    public static BlockResult<T> Skip() => new(default, null, null, BlockResultType.Skip);
-    public static new BlockResult<T> Error(string? message = null) => new(default, null, message, BlockResultType.Error);
-    public static BlockResult<T> BackToCheckpoint(string? key = null) => new(default, key, null, BlockResultType.BackToCheckpoint);
-    public static BlockResult<T> BackToExit(string? key = null) => new(default, key, null, BlockResultType.BackToExit);
+    public static new BlockResult<T> Completed(string? message = null) => new(default, null, message, BlockResultType.Completed, null);
+    public static BlockResult<T> Skip() => new(default, null, null, BlockResultType.Skip, null);
+    public static new BlockResult<T> Error(string? message = null, Exception? exception = null) => new(default, null, message, BlockResultType.Error, exception);
+    public static BlockResult<T> BackToCheckpoint(string? key = null) => new(default, key, null, BlockResultType.BackToCheckpoint, null);
+    public static BlockResult<T> BackToExit(string? key = null) => new(default, key, null, BlockResultType.BackToExit, null);
 }

PipelineBlocks/Models/PipelineBlock.cs

@@ -33,18 +33,25 @@ async Task<BlockResult> IExecutableBlock.ExecuteSelfAsync(CancellationToken canc
             IsCompleted = true;
             return BlockResult.Error("No job");
         }
-        BlockResult<T>? result = await Job.Invoke(this, cancellationToken);
-        return result is null
-            ? BlockResult.Error("Job returned null")
-            : result.ResultType switch
-            {
-                BlockResultType.Exit or BlockResultType.Completed => Exit(result),
-                BlockResultType.Forward => Forward(result),
-                BlockResultType.BackToCheckpoint => BackToCheckpoint(result),
-                BlockResultType.BackToExit => BackToExit(result),
-                BlockResultType.Skip => Skip(),
-                _ => result
-            };
+        try
+        {
+            BlockResult<T>? result = await Job.Invoke(this, cancellationToken);
+            return result is null
+                ? BlockResult.Error("Job returned null")
+                : result.ResultType switch
+                {
+                    BlockResultType.Exit or BlockResultType.Completed => Exit(result),
+                    BlockResultType.Forward => Forward(result),
+                    BlockResultType.BackToCheckpoint => BackToCheckpoint(result),
+                    BlockResultType.BackToExit => BackToExit(result),
+                    BlockResultType.Skip => Skip(),
+                    _ => result
+                };
+        }
+        catch (Exception ex)
+        {
+            return BlockResult.Error("Job execution failed", ex);
+        }
     }
 
     public async Task<BlockResult> ExecuteAsync(CancellationToken cancellationToken = default)

PipelineBlocksTests/Models/PipelineBlockTests.cs

@@ -175,6 +175,21 @@ public async Task ExecuteAsync_HasJob_ShouldReturnTrue()
         (await act.Should().NotThrowAsync()).Which.ResultType.Should().Be(BlockResultType.Completed);
     }
 
+    [TestMethod()]
+    public async Task ExecuteAsync_Exception_ShouldReturnError()
+    {
+        // arrange
+        var exception = new Exception("Job execution failed");
+        PipelineBlock<int> block = new()
+        {
+            Job = (x, _) => throw exception
+        };
+        // act
+        Func<Task<BlockResult>> act = () => block.ExecuteAsync();
+        // assert
+        (await act.Should().NotThrowAsync()).Which.Should().BeEquivalentTo(BlockResult.Error("Job execution failed", exception));
+    }
+
     [TestMethod()]
     public void IsCompleted_NotExecuted_ShouldReturnFalse()
     {