Add a way to restart a workflow instance

src/OrchardCore.Modules/OrchardCore.Contents/Workflows/Activities/ContentActivity.cs

@@ -1,8 +1,9 @@
-using System;
 using System.Collections.Generic;
+using System.Threading;
 using System.Threading.Tasks;
 using Microsoft.Extensions.Localization;
 using Newtonsoft.Json;
+using Newtonsoft.Json.Linq;
 using OrchardCore.ContentManagement;
 using OrchardCore.ContentManagement.Workflows;
 using OrchardCore.Workflows.Abstractions.Models;
@@ -17,7 +18,10 @@ public abstract class ContentActivity : Activity
     {
         protected readonly IStringLocalizer S;
 
-        protected ContentActivity(IContentManager contentManager, IWorkflowScriptEvaluator scriptEvaluator, IStringLocalizer localizer)
+        protected ContentActivity(
+            IContentManager contentManager,
+            IWorkflowScriptEvaluator scriptEvaluator,
+            IStringLocalizer localizer)
         {
             ContentManager = contentManager;
             ScriptEvaluator = scriptEvaluator;
@@ -68,6 +72,40 @@ public override ActivityExecutionResult Execute(WorkflowExecutionContext workflo
             return Outcomes("Done");
         }
 
+        public override async Task OnWorkflowRestartingAsync(WorkflowExecutionContext workflowContext, CancellationToken cancellationToken = default)
+        {
+            ContentItem contentItem = null;
+
+            if (workflowContext.Input.TryGetValue(ContentEventConstants.ContentEventInputKey, out var contentEvent))
+            {
+                var contentEventContext = ((JObject)contentEvent).ToObject<ContentEventContext>();
+
+                if (contentEventContext?.ContentItemVersionId != null)
+                {
+                    contentItem = await ContentManager.GetVersionAsync(contentEventContext.ContentItemVersionId);
+                }
+                if (contentItem == null && contentEventContext?.ContentItemId != null)
+                {
+                    contentItem = await ContentManager.GetAsync(contentEventContext.ContentItemId);
+                }
+            }
+
+            if (contentItem == null && workflowContext.Input.TryGetValue(ContentEventConstants.ContentItemInputKey, out var contentItemEvent))
+            {
+                var item = ((JObject)contentItemEvent).ToObject<ContentItem>();
+
+                if (item?.ContentItemId != null)
+                {
+                    contentItem = await ContentManager.GetAsync(item.ContentItemId);
+                }
+            }
+
+            if (contentItem != null)
+            {
+                workflowContext.Input[ContentEventConstants.ContentItemInputKey] = contentItem;
+            }
+        }
+
         protected virtual async Task<IContent> GetContentAsync(WorkflowExecutionContext workflowContext)
         {
             IContent content;

src/OrchardCore.Modules/OrchardCore.Contents/Workflows/Handlers/ContentsHandler.cs

@@ -58,7 +58,8 @@ private Task TriggerWorkflowEventAsync(string name, ContentItem contentItem)
             {
                 Name = name,
                 ContentType = contentItem.ContentType,
-                ContentItemId = contentItem.ContentItemId
+                ContentItemId = contentItem.ContentItemId,
+                ContentItemVersionId = contentItem.ContentItemVersionId,
             };
 
             var input = new Dictionary<string, object>

src/OrchardCore.Modules/OrchardCore.Workflows/Controllers/WorkflowController.cs

@@ -15,6 +15,7 @@
 using OrchardCore.DisplayManagement;
 using OrchardCore.DisplayManagement.ModelBinding;
 using OrchardCore.DisplayManagement.Notify;
+using OrchardCore.Locking.Distributed;
 using OrchardCore.Mvc.Core.Utilities;
 using OrchardCore.Navigation;
 using OrchardCore.Routing;
@@ -42,6 +43,7 @@ public class WorkflowController : Controller
         private readonly IUpdateModelAccessor _updateModelAccessor;
         protected readonly dynamic New;
         protected readonly IHtmlLocalizer H;
+        private readonly IDistributedLock _distributedLock;
         protected readonly IStringLocalizer S;
 
         public WorkflowController(
@@ -55,6 +57,7 @@ public WorkflowController(
             IShapeFactory shapeFactory,
             INotifier notifier,
             IHtmlLocalizer<WorkflowController> htmlLocalizer,
+            IDistributedLock distributedLock,
             IStringLocalizer<WorkflowController> stringLocalizer,
             IUpdateModelAccessor updateModelAccessor)
         {
@@ -69,6 +72,7 @@ public WorkflowController(
             _updateModelAccessor = updateModelAccessor;
             New = shapeFactory;
             H = htmlLocalizer;
+            _distributedLock = distributedLock;
             S = stringLocalizer;
         }
 
@@ -242,6 +246,54 @@ public async Task<IActionResult> Delete(long id)
             return RedirectToAction(nameof(Index), new { workflowTypeId = workflowType.Id });
         }
 
+        [HttpPost]
+        public async Task<IActionResult> Restart(long id)
+        {
+            if (!await _authorizationService.AuthorizeAsync(User, Permissions.ManageWorkflows))
+            {
+                return Forbid();
+            }
+
+            var workflow = await _workflowStore.GetAsync(id);
+
+            if (workflow == null)
+            {
+                return NotFound();
+            }
+
+            var workflowType = await _workflowTypeStore.GetAsync(workflow.WorkflowTypeId);
+
+            if (workflowType == null)
+            {
+                return NotFound();
+            }
+
+            // If a singleton, try to acquire a lock per workflow type.
+            (var locker, var locked) = await _distributedLock.TryAcquireWorkflowTypeLockAsync(workflowType);
+            if (!locked)
+            {
+                await _notifier.ErrorAsync(H["Another instance is already running.", id]);
+            }
+            else
+            {
+                await using var acquiredLock = locker;
+
+                // Check if this is a workflow singleton and there's already an halted instance on any activity.
+                if (workflowType.IsSingleton && await _workflowStore.HasHaltedInstanceAsync(workflowType.WorkflowTypeId))
+                {
+                    await _notifier.ErrorAsync(H["Another instance is already running.", id]);
+                }
+                else
+                {
+                    await _workflowManager.RestartWorkflowAsync(workflow, workflowType);
+
+                    await _notifier.SuccessAsync(H["Workflow {0} has been restarted.", id]);
+                }
+            }
+
+            return RedirectToAction(nameof(Index), new { workflowTypeId = workflowType.Id });
+        }
+
         [HttpPost]
         [ActionName(nameof(Index))]
         [FormValueRequired("submit.BulkAction")]