Workflow life cycle events (danielgerlag#215)

Author: danielgerlag

ReleaseNotes/1.6.9.md

@@ -0,0 +1,5 @@
+# Workflow Core 1.6.9
+
+This release adds functionality to subscribe to workflow life cycle events (WorkflowStarted, WorkflowComplete, WorkflowError, WorkflowSuspended, WorkflowResumed, StepStarted, StepCompleted, etc...)
+This can be achieved by either grabbing the `ILifeCycleEventHub` implementation from the IoC container and subscribing to events there, or attach an event on the workflow host class `IWorkflowHost.OnLifeCycleEvent`.
+This implementation only publishes events to the local node... we will still need to implement a distributed version of the EventHub to solve the problem for multi-node clusters.

WorkflowCore.sln

@@ -93,6 +93,7 @@ Project("{2150E333-8FDC-42A3-9474-1A3956D46DE8}") = "ReleaseNotes", "ReleaseNote
 		ReleaseNotes\1.6.0.md = ReleaseNotes\1.6.0.md
 		ReleaseNotes\1.6.6.md = ReleaseNotes\1.6.6.md
 		ReleaseNotes\1.6.8.md = ReleaseNotes\1.6.8.md
+		ReleaseNotes\1.6.9.md = ReleaseNotes\1.6.9.md
 	EndProjectSection
 EndProject
 Project("{9A19103F-16F7-4668-BE54-9A1E7A4F7556}") = "WorkflowCore.Sample14", "src\samples\WorkflowCore.Sample14\WorkflowCore.Sample14.csproj", "{6BC66637-B42A-4334-ADFB-DBEC9F29D293}"

src/WorkflowCore/Interface/IExecutionResultProcessor.cs

@@ -5,7 +5,7 @@ namespace WorkflowCore.Interface
 {
     public interface IExecutionResultProcessor
     {
-        void HandleStepException(WorkflowInstance workflow, WorkflowDefinition def, ExecutionPointer pointer, WorkflowStep step);
+        void HandleStepException(WorkflowInstance workflow, WorkflowDefinition def, ExecutionPointer pointer, WorkflowStep step, Exception exception);
         void ProcessExecutionResult(WorkflowInstance workflow, WorkflowDefinition def, ExecutionPointer pointer, WorkflowStep step, ExecutionResult result, WorkflowExecutorResult workflowResult);
     }
 }

src/WorkflowCore/Interface/ILifeCycleEventHub.cs

@@ -0,0 +1,14 @@
+using System;
+using System.Collections.Generic;
+using System.Text;
+using System.Threading.Tasks;
+using WorkflowCore.Models.LifeCycleEvents;
+
+namespace WorkflowCore.Interface
+{
+    public interface ILifeCycleEventHub
+    {
+        Task PublishNotification(LifeCycleEvent evt);
+        void Subscribe(Action<LifeCycleEvent> action);
+    }
+}

src/WorkflowCore/Interface/ILifeCycleEventPublisher.cs

@@ -0,0 +1,12 @@
+using System;
+using System.Collections.Generic;
+using System.Text;
+using WorkflowCore.Models.LifeCycleEvents;
+
+namespace WorkflowCore.Interface
+{
+    public interface ILifeCycleEventPublisher : IBackgroundTask
+    {
+        void PublishNotification(LifeCycleEvent evt);
+    }
+}

src/WorkflowCore/Interface/IWorkflowErrorHandler.cs

@@ -0,0 +1,13 @@
+using System;
+using System.Collections.Generic;
+using System.Text;
+using WorkflowCore.Models;
+
+namespace WorkflowCore.Interface
+{
+    public interface IWorkflowErrorHandler
+    {
+        WorkflowErrorHandling Type { get; }
+        void Handle(WorkflowInstance workflow, WorkflowDefinition def, ExecutionPointer pointer, WorkflowStep step, Exception exception, Queue<ExecutionPointer> bubbleUpQueue);
+    }
+}

src/WorkflowCore/Interface/IWorkflowHost.cs

@@ -2,6 +2,7 @@
 using System;
 using System.Threading.Tasks;
 using WorkflowCore.Models;
+using WorkflowCore.Models.LifeCycleEvents;
 
 namespace WorkflowCore.Interface
 {
@@ -19,6 +20,7 @@ public interface IWorkflowHost : IWorkflowController
 
 
         event StepErrorEventHandler OnStepError;
+        event LifeCycleEventHandler OnLifeCycleEvent;
         void ReportStepError(WorkflowInstance workflow, WorkflowStep step, Exception exception);
 
         //public dependencies to allow for extension method access
@@ -32,4 +34,5 @@ public interface IWorkflowHost : IWorkflowController
     }
 
     public delegate void StepErrorEventHandler(WorkflowInstance workflow, WorkflowStep step, Exception exception);
-}
+    public delegate void LifeCycleEventHandler(LifeCycleEvent evt);
+}

src/WorkflowCore/Models/LifeCycleEvents/LifeCycleEvent.cs

@@ -0,0 +1,19 @@
+using System;
+using System.Collections.Generic;
+using System.Text;
+
+namespace WorkflowCore.Models.LifeCycleEvents
+{
+    public abstract class LifeCycleEvent
+    {
+        public DateTime EventTimeUtc { get; set; }
+
+        public string WorkflowInsanceId { get; set; }
+
+        public string WorkflowDefinitionId { get; set; }
+
+        public int Version { get; set; }
+
+        public string Reference { get; set; }
+    }
+}

src/WorkflowCore/Models/LifeCycleEvents/StepCompleted.cs

@@ -0,0 +1,13 @@
+using System;
+using System.Collections.Generic;
+using System.Text;
+
+namespace WorkflowCore.Models.LifeCycleEvents
+{
+    public class StepCompleted : LifeCycleEvent
+    {
+        public string ExecutionPointerId { get; set; }
+
+        public int StepId { get; set; }
+    }
+}

src/WorkflowCore/Models/LifeCycleEvents/StepStarted.cs

@@ -0,0 +1,13 @@
+using System;
+using System.Collections.Generic;
+using System.Text;
+
+namespace WorkflowCore.Models.LifeCycleEvents
+{
+    public class StepStarted : LifeCycleEvent
+    {
+        public string ExecutionPointerId { get; set; }
+
+        public int StepId { get; set; }
+    }
+}