Merge pull request #6183 from elsa-workflows/bug/background-execution-cancels-itself

Introduce job unscheduling functionality

src/common/Elsa.Mediator/Contracts/IJobQueue.cs

@@ -23,6 +23,13 @@ public interface IJobQueue
     /// <returns>The ID of the job.</returns>
     string Enqueue(Func<CancellationToken, Task> job);
     
+    /// <summary>
+    /// Dequeues a job.
+    /// </summary>
+    /// <param name="jobId">The ID of the job to dequeue.</param>
+    /// <returns><c>true</c> if the job was dequeued; otherwise, <c>false</c>.</returns>
+    bool Dequeue(string jobId);
+    
     /// <summary>
     /// Cancels a job.
     /// </summary>

src/common/Elsa.Mediator/Services/JobQueue.cs

@@ -40,6 +40,16 @@ public class JobQueue(IJobsChannel jobsChannel, ILogger<JobQueue> logger) : IJob
         return jobItem.JobId;
     }
 
+    /// <inheritdoc />
+    public bool Dequeue(string jobId)
+    {
+        if (!_pendingItems.TryRemove(jobId, out _))
+            if (!_scheduledItems.TryRemove(jobId, out _))
+                return false;
+
+        return true;
+    }
+
     /// <inheritdoc />
     public bool Cancel(string jobId)
     {

src/modules/Elsa.Hangfire/Services/HangfireBackgroundActivityScheduler.cs

@@ -32,6 +32,12 @@ public class HangfireBackgroundActivityScheduler(IBackgroundJobClient background
         return Task.FromResult(jobId);
     }
 
+    public Task UnscheduledAsync(string jobId, CancellationToken cancellationToken = default)
+    {
+        backgroundJobClient.Delete(jobId);
+        return Task.CompletedTask;
+    }
+
     /// <inheritdoc />
     public Task CancelAsync(string jobId, CancellationToken cancellationToken = default)
     {

src/modules/Elsa.Workflows.Runtime/Contracts/IBackgroundActivityScheduler.cs

@@ -26,6 +26,11 @@ public interface IBackgroundActivityScheduler
     /// <param name="cancellationToken">The cancellation token.</param>
     /// <returns>A handle representing the asynchronous invocation.</returns>
     Task<string> ScheduleAsync(ScheduledBackgroundActivity scheduledBackgroundActivity, CancellationToken cancellationToken = default);
+    
+    /// <summary>
+    /// Removes the specified job from the schedule.
+    /// </summary>
+    Task UnscheduledAsync(string jobId, CancellationToken cancellationToken = default);
 
     /// <summary>
     /// Cancels the specified job.

src/modules/Elsa.Workflows.Runtime/Handlers/CancelBackgroundActivities.cs

@@ -22,7 +22,7 @@ public class CancelBackgroundActivities(IBackgroundActivityScheduler backgroundA
         {
             var payload = removedBookmark.GetPayload<BackgroundActivityStimulus>();
             if (payload.JobId != null)
-                await backgroundActivityScheduler.CancelAsync(payload.JobId, cancellationToken);
+                await backgroundActivityScheduler.UnscheduledAsync(payload.JobId, cancellationToken);
         }
     }
 }

src/modules/Elsa.Workflows.Runtime/Services/LocalBackgroundActivityScheduler.cs

@@ -27,6 +27,12 @@ public class LocalBackgroundActivityScheduler(IJobQueue jobQueue, IServiceScopeF
         return Task.FromResult(jobId);
     }
 
+    public Task UnscheduledAsync(string jobId, CancellationToken cancellationToken = default)
+    {
+        jobQueue.Dequeue(jobId);
+        return Task.CompletedTask;
+    }
+
     /// <inheritdoc />
     public Task CancelAsync(string jobId, CancellationToken cancellationToken = default)
     {