| | | 1 | | using Google.Cloud.PubSub.V1; |
| | | 2 | | |
| | | 3 | | namespace AsyncResponse.Transports.GooglePubSub; |
| | | 4 | | |
| | | 5 | | /// <summary> |
| | | 6 | | /// Controls when a Google Pub/Sub message is acknowledged relative to AsyncResponse handling. |
| | | 7 | | /// </summary> |
| | | 8 | | public enum GooglePubSubAckMode |
| | | 9 | | { |
| | | 10 | | /// <summary> |
| | | 11 | | /// ACK only after the AsyncResponse handler completes successfully; NACK if the handler throws. |
| | | 12 | | /// This is the default and preserves Pub/Sub retry semantics for handler failures. |
| | | 13 | | /// </summary> |
| | | 14 | | AckAfterHandlerCompletes = 0, |
| | | 15 | | |
| | | 16 | | /// <summary> |
| | | 17 | | /// ACK immediately after the message is accepted into a bounded in-process background queue. |
| | | 18 | | /// Handler failures are logged and reported through |
| | | 19 | | /// <see cref="GooglePubSubSubscriberOptions.OnBackgroundFailure"/> because Pub/Sub has already |
| | | 20 | | /// been ACKed. |
| | | 21 | | /// </summary> |
| | | 22 | | AckAfterEnqueue = 1 |
| | | 23 | | } |
| | | 24 | | |
| | | 25 | | /// <summary> |
| | | 26 | | /// Describes a handler failure that happened after a Google Pub/Sub message was already ACKed by |
| | | 27 | | /// <see cref="GooglePubSubAckMode.AckAfterEnqueue"/>. |
| | | 28 | | /// </summary> |
| | | 29 | | public sealed class GooglePubSubBackgroundFailureContext |
| | | 30 | | { |
| | | 31 | | internal GooglePubSubBackgroundFailureContext( |
| | | 32 | | string subscriptionId, |
| | | 33 | | string subscriberRole, |
| | | 34 | | PubsubMessage message, |
| | | 35 | | Exception exception) |
| | | 36 | | { |
| | | 37 | | SubscriptionId = subscriptionId; |
| | | 38 | | SubscriberRole = subscriberRole; |
| | | 39 | | Message = message; |
| | | 40 | | Exception = exception; |
| | | 41 | | } |
| | | 42 | | |
| | | 43 | | /// <summary>The subscription whose background worker was handling the message.</summary> |
| | | 44 | | public string SubscriptionId { get; } |
| | | 45 | | |
| | | 46 | | /// <summary>The logical subscriber role, such as <c>Worker</c> or <c>ResponseIngress</c>.</summary> |
| | | 47 | | public string SubscriberRole { get; } |
| | | 48 | | |
| | | 49 | | /// <summary>The Pub/Sub message that failed after being ACKed.</summary> |
| | | 50 | | public PubsubMessage Message { get; } |
| | | 51 | | |
| | | 52 | | /// <summary>The Pub/Sub message id, when provided by Google Pub/Sub.</summary> |
| | | 53 | | public string MessageId => Message.MessageId; |
| | | 54 | | |
| | | 55 | | /// <summary>The exception thrown by the background handler.</summary> |
| | | 56 | | public Exception Exception { get; } |
| | | 57 | | } |
| | | 58 | | |
| | | 59 | | /// <summary> |
| | | 60 | | /// Per-subscription Google Pub/Sub subscriber behavior. |
| | | 61 | | /// </summary> |
| | | 62 | | public sealed class GooglePubSubSubscriberOptions |
| | | 63 | | { |
| | | 64 | | /// <summary> |
| | | 65 | | /// Controls when the Pub/Sub callback returns ACK. Defaults to |
| | | 66 | | /// <see cref="GooglePubSubAckMode.AckAfterHandlerCompletes"/>. |
| | | 67 | | /// </summary> |
| | | 68 | | public GooglePubSubAckMode AckMode { get; set; } = GooglePubSubAckMode.AckAfterHandlerCompletes; |
| | | 69 | | |
| | | 70 | | /// <summary> |
| | | 71 | | /// Number of background workers used by <see cref="GooglePubSubAckMode.AckAfterEnqueue"/>. |
| | | 72 | | /// Must be explicitly set to a positive value for early ACK mode. |
| | | 73 | | /// Values greater than one allow concurrent handling and therefore do not preserve message |
| | | 74 | | /// ordering. |
| | | 75 | | /// </summary> |
| | | 76 | | public int BackgroundWorkerCount { get; set; } |
| | | 77 | | |
| | | 78 | | /// <summary> |
| | | 79 | | /// Maximum number of messages waiting in the background queue for |
| | | 80 | | /// <see cref="GooglePubSubAckMode.AckAfterEnqueue"/>. Must be explicitly set to a positive value. |
| | | 81 | | /// When full, the Pub/Sub callback parks awaiting queue space and ACKs once the message is |
| | | 82 | | /// accepted — it does not NACK on a full queue; NACK is returned only when the write fails |
| | | 83 | | /// (shutdown/disposal), so the message is redelivered rather than lost. |
| | | 84 | | /// </summary> |
| | | 85 | | public int BackgroundQueueCapacity { get; set; } |
| | | 86 | | |
| | | 87 | | /// <summary> |
| | | 88 | | /// Maximum time to wait for queued/running background handlers while the hosted subscriber stops. |
| | | 89 | | /// </summary> |
| | 3 | 90 | | public TimeSpan BackgroundDrainTimeout { get; set; } = TimeSpan.FromSeconds(20); |
| | | 91 | | |
| | | 92 | | /// <summary> |
| | | 93 | | /// Optional callback invoked when a background handler fails after the message was already ACKed. |
| | | 94 | | /// Use it to publish to a dead-letter path, increment operator-visible metrics, or alert on |
| | | 95 | | /// already-ACKed work that Pub/Sub cannot redeliver. |
| | | 96 | | /// </summary> |
| | | 97 | | public Func<GooglePubSubBackgroundFailureContext, ValueTask>? OnBackgroundFailure { get; set; } |
| | | 98 | | |
| | | 99 | | /// <summary> |
| | | 100 | | /// Explicitly opts this subscriber into ACK-after-enqueue behavior. |
| | | 101 | | /// </summary> |
| | | 102 | | public GooglePubSubSubscriberOptions UseAckAfterEnqueue( |
| | | 103 | | int backgroundWorkerCount, |
| | | 104 | | int backgroundQueueCapacity, |
| | | 105 | | TimeSpan? backgroundDrainTimeout = null) |
| | | 106 | | { |
| | 3 | 107 | | ArgumentOutOfRangeException.ThrowIfNegativeOrZero(backgroundWorkerCount); |
| | 3 | 108 | | ArgumentOutOfRangeException.ThrowIfNegativeOrZero(backgroundQueueCapacity); |
| | | 109 | | |
| | 3 | 110 | | if (backgroundDrainTimeout is { } timeout && timeout <= TimeSpan.Zero) |
| | 3 | 111 | | throw new ArgumentOutOfRangeException(nameof(backgroundDrainTimeout), timeout, "Drain timeout must be positi |
| | | 112 | | |
| | 3 | 113 | | AckMode = GooglePubSubAckMode.AckAfterEnqueue; |
| | 3 | 114 | | BackgroundWorkerCount = backgroundWorkerCount; |
| | 3 | 115 | | BackgroundQueueCapacity = backgroundQueueCapacity; |
| | | 116 | | |
| | 3 | 117 | | if (backgroundDrainTimeout is not null) |
| | 3 | 118 | | BackgroundDrainTimeout = backgroundDrainTimeout.Value; |
| | | 119 | | |
| | 3 | 120 | | return this; |
| | | 121 | | } |
| | | 122 | | } |