| | | 1 | | namespace Elsa.Workflows.Runtime; |
| | | 2 | | |
| | | 3 | | /// <summary> |
| | | 4 | | /// The result of an activation-gate evaluation. Dispose after the new instance is persisted |
| | | 5 | | /// so the uniqueness check becomes visible to waiters. |
| | | 6 | | /// </summary> |
| | | 7 | | public sealed class WorkflowActivationLease : IAsyncDisposable |
| | | 8 | | { |
| | | 9 | | private IAsyncDisposable? _lockHandle; |
| | | 10 | | private CancellationTokenSource? _linkedCancellationTokenSource; |
| | | 11 | | private readonly CancellationToken _effectiveCancellationToken; |
| | | 12 | | |
| | | 13 | | /// <summary> |
| | | 14 | | /// A lease that denies activation. No lock is held. |
| | | 15 | | /// </summary> |
| | 13 | 16 | | public static WorkflowActivationLease Denied { get; } = new(false, null); |
| | | 17 | | |
| | | 18 | | public WorkflowActivationLease(bool canStart, IAsyncDisposable? lockHandle) |
| | 4 | 19 | | : this(canStart, lockHandle, CancellationToken.None, null) |
| | | 20 | | { |
| | 4 | 21 | | } |
| | | 22 | | |
| | | 23 | | internal WorkflowActivationLease(bool canStart, IAsyncDisposable? lockHandle, CancellationToken effectiveCancellatio |
| | 5 | 24 | | : this(canStart, lockHandle, effectiveCancellationToken, null) |
| | | 25 | | { |
| | 5 | 26 | | } |
| | | 27 | | |
| | 185 | 28 | | internal WorkflowActivationLease(bool canStart, IAsyncDisposable? lockHandle, CancellationToken effectiveCancellatio |
| | | 29 | | { |
| | 185 | 30 | | CanStart = canStart; |
| | 185 | 31 | | _lockHandle = lockHandle; |
| | 185 | 32 | | _effectiveCancellationToken = effectiveCancellationToken; |
| | 185 | 33 | | _linkedCancellationTokenSource = linkedCancellationTokenSource; |
| | 185 | 34 | | } |
| | | 35 | | |
| | | 36 | | /// <summary> |
| | | 37 | | /// Whether a new workflow instance may be created. |
| | | 38 | | /// </summary> |
| | 184 | 39 | | public bool CanStart { get; } |
| | | 40 | | |
| | | 41 | | internal CancellationToken GetEffectiveCancellationToken(CancellationToken fallbackToken) => |
| | 170 | 42 | | _effectiveCancellationToken.CanBeCanceled ? _effectiveCancellationToken : fallbackToken; |
| | | 43 | | |
| | | 44 | | /// <inheritdoc /> |
| | | 45 | | public async ValueTask DisposeAsync() |
| | | 46 | | { |
| | 193 | 47 | | var lockHandle = Interlocked.Exchange(ref _lockHandle, null); |
| | 193 | 48 | | var linkedCancellationTokenSource = Interlocked.Exchange(ref _linkedCancellationTokenSource, null); |
| | | 49 | | |
| | | 50 | | try |
| | | 51 | | { |
| | 193 | 52 | | if (lockHandle != null) |
| | 26 | 53 | | await lockHandle.DisposeAsync(); |
| | 193 | 54 | | } |
| | | 55 | | finally |
| | | 56 | | { |
| | 193 | 57 | | linkedCancellationTokenSource?.Dispose(); |
| | | 58 | | } |
| | 193 | 59 | | } |
| | | 60 | | } |