| | | 1 | | namespace AsyncResponse.Transports.RabbitMQ; |
| | | 2 | | |
| | | 3 | | /// <summary> |
| | | 4 | | /// Controls when a RabbitMQ delivery is acknowledged relative to AsyncResponse handling. |
| | | 5 | | /// </summary> |
| | | 6 | | public enum RabbitMqAckMode |
| | | 7 | | { |
| | | 8 | | /// <summary> |
| | | 9 | | /// ACK only after the AsyncResponse handler completes successfully; NACK/requeue if the handler |
| | | 10 | | /// throws. This is the default and preserves broker redelivery for handler failures. |
| | | 11 | | /// </summary> |
| | | 12 | | AckAfterHandlerCompletes = 0, |
| | | 13 | | |
| | | 14 | | /// <summary> |
| | | 15 | | /// ACK immediately after the delivery is accepted into a bounded in-process background queue. |
| | | 16 | | /// Handler failures are logged and reported through <see cref="RabbitMqSubscriberOptions.OnBackgroundFailure"/> |
| | | 17 | | /// because RabbitMQ has already been ACKed. |
| | | 18 | | /// </summary> |
| | | 19 | | AckAfterEnqueue = 1 |
| | | 20 | | } |
| | | 21 | | |
| | | 22 | | /// <summary> |
| | | 23 | | /// Describes a handler failure that happened after a RabbitMQ delivery was already ACKed by |
| | | 24 | | /// <see cref="RabbitMqAckMode.AckAfterEnqueue"/>. |
| | | 25 | | /// </summary> |
| | | 26 | | public sealed class RabbitMqBackgroundFailureContext |
| | | 27 | | { |
| | 8 | 28 | | internal RabbitMqBackgroundFailureContext( |
| | 8 | 29 | | string queue, |
| | 8 | 30 | | string subscriberRole, |
| | 8 | 31 | | string exchange, |
| | 8 | 32 | | string routingKey, |
| | 8 | 33 | | ulong deliveryTag, |
| | 8 | 34 | | Exception exception) |
| | | 35 | | { |
| | 8 | 36 | | Queue = queue; |
| | 8 | 37 | | SubscriberRole = subscriberRole; |
| | 8 | 38 | | Exchange = exchange; |
| | 8 | 39 | | RoutingKey = routingKey; |
| | 8 | 40 | | DeliveryTag = deliveryTag; |
| | 8 | 41 | | Exception = exception; |
| | 8 | 42 | | } |
| | | 43 | | |
| | | 44 | | /// <summary>The queue whose background worker was handling the delivery.</summary> |
| | 2 | 45 | | public string Queue { get; } |
| | | 46 | | |
| | | 47 | | /// <summary>The logical subscriber role, such as <c>Worker</c> or <c>ResponseIngress</c>.</summary> |
| | 2 | 48 | | public string SubscriberRole { get; } |
| | | 49 | | |
| | | 50 | | /// <summary>The exchange the delivery came from.</summary> |
| | 2 | 51 | | public string Exchange { get; } |
| | | 52 | | |
| | | 53 | | /// <summary>The routing key the delivery came with.</summary> |
| | 2 | 54 | | public string RoutingKey { get; } |
| | | 55 | | |
| | | 56 | | /// <summary>The RabbitMQ delivery tag.</summary> |
| | 2 | 57 | | public ulong DeliveryTag { get; } |
| | | 58 | | |
| | | 59 | | /// <summary>The exception thrown by the background handler.</summary> |
| | 4 | 60 | | public Exception Exception { get; } |
| | | 61 | | } |
| | | 62 | | |
| | | 63 | | /// <summary> |
| | | 64 | | /// Per-queue RabbitMQ subscriber behavior. |
| | | 65 | | /// </summary> |
| | | 66 | | public sealed class RabbitMqSubscriberOptions |
| | | 67 | | { |
| | | 68 | | /// <summary> |
| | | 69 | | /// Controls when the RabbitMQ delivery is ACKed. Defaults to |
| | | 70 | | /// <see cref="RabbitMqAckMode.AckAfterHandlerCompletes"/>. |
| | | 71 | | /// </summary> |
| | | 72 | | public RabbitMqAckMode AckMode { get; set; } = RabbitMqAckMode.AckAfterHandlerCompletes; |
| | | 73 | | |
| | | 74 | | /// <summary> |
| | | 75 | | /// Prefetch count set through <c>basic.qos</c>. Default: <c>16</c>. |
| | | 76 | | /// </summary> |
| | | 77 | | public ushort PrefetchCount { get; set; } = 16; |
| | | 78 | | |
| | | 79 | | /// <summary> |
| | | 80 | | /// Maximum number of times a delivery may be attempted in <see cref="RabbitMqAckMode.AckAfterHandlerCompletes"/> |
| | | 81 | | /// mode before a failing handler rejects it without requeue (dead-lettering it via |
| | | 82 | | /// <see cref="RabbitMqAsyncResponseOptions.DeadLetterExchange"/> when configured, otherwise dropping it). |
| | | 83 | | /// Default: <c>0</c>, meaning unlimited — a failing handler requeues forever, which can hot-loop on a poison |
| | | 84 | | /// message. Set a positive cap (with a dead-letter exchange) to bound retries. The attempt count is read from |
| | | 85 | | /// the broker's <c>x-death</c> header and the <c>redelivered</c> flag; because <c>basic.nack</c> requeue does |
| | | 86 | | /// not increment <c>x-death</c>, the resolved attempt never exceeds 2 on its own, so values above 2 only take |
| | | 87 | | /// effect when the dead-letter path forms a TTL-retry cycle that re-delivers the message (each dead-letter |
| | | 88 | | /// hop increments <c>x-death</c>). A value above 2 without such a cycle behaves like 2 and logs a startup |
| | | 89 | | /// warning. Ignored for <see cref="RabbitMqAckMode.AckAfterEnqueue"/>, which acknowledges before handling |
| | | 90 | | /// and never redelivers. |
| | | 91 | | /// </summary> |
| | | 92 | | public int MaxDeliveryAttempts { get; set; } |
| | | 93 | | |
| | | 94 | | /// <summary> |
| | | 95 | | /// Number of background workers used by <see cref="RabbitMqAckMode.AckAfterEnqueue"/>. |
| | | 96 | | /// Must be explicitly set to a positive value for early ACK mode. |
| | | 97 | | /// </summary> |
| | | 98 | | public int BackgroundWorkerCount { get; set; } |
| | | 99 | | |
| | | 100 | | /// <summary> |
| | | 101 | | /// Maximum number of deliveries waiting in the background queue for |
| | | 102 | | /// <see cref="RabbitMqAckMode.AckAfterEnqueue"/>. When full, the channel's delivery loop pauses |
| | | 103 | | /// (deliveries are dispatched per channel, sequentially) until a worker frees capacity. |
| | | 104 | | /// </summary> |
| | | 105 | | public int BackgroundQueueCapacity { get; set; } |
| | | 106 | | |
| | | 107 | | /// <summary> |
| | | 108 | | /// Maximum time to wait for queued/running background handlers while the hosted subscriber stops. |
| | | 109 | | /// </summary> |
| | | 110 | | public TimeSpan BackgroundDrainTimeout { get; set; } = TimeSpan.FromSeconds(20); |
| | | 111 | | |
| | | 112 | | /// <summary> |
| | | 113 | | /// Optional callback invoked when a background handler fails after the delivery was already ACKed. |
| | | 114 | | /// Use it to publish to a dead-letter path, increment operator-visible metrics, or alert on |
| | | 115 | | /// already-ACKed work that RabbitMQ cannot redeliver. |
| | | 116 | | /// </summary> |
| | | 117 | | public Func<RabbitMqBackgroundFailureContext, ValueTask>? OnBackgroundFailure { get; set; } |
| | | 118 | | |
| | | 119 | | /// <summary> |
| | | 120 | | /// Explicitly opts this subscriber into ACK-after-enqueue behavior. |
| | | 121 | | /// </summary> |
| | | 122 | | public RabbitMqSubscriberOptions UseAckAfterEnqueue( |
| | | 123 | | int backgroundWorkerCount, |
| | | 124 | | int backgroundQueueCapacity, |
| | | 125 | | TimeSpan? backgroundDrainTimeout = null) |
| | | 126 | | { |
| | | 127 | | ArgumentOutOfRangeException.ThrowIfNegativeOrZero(backgroundWorkerCount); |
| | | 128 | | ArgumentOutOfRangeException.ThrowIfNegativeOrZero(backgroundQueueCapacity); |
| | | 129 | | |
| | | 130 | | if (backgroundDrainTimeout is { } timeout && timeout <= TimeSpan.Zero) |
| | | 131 | | throw new ArgumentOutOfRangeException(nameof(backgroundDrainTimeout), timeout, "Drain timeout must be positi |
| | | 132 | | |
| | | 133 | | AckMode = RabbitMqAckMode.AckAfterEnqueue; |
| | | 134 | | BackgroundWorkerCount = backgroundWorkerCount; |
| | | 135 | | BackgroundQueueCapacity = backgroundQueueCapacity; |
| | | 136 | | |
| | | 137 | | if (backgroundDrainTimeout is not null) |
| | | 138 | | BackgroundDrainTimeout = backgroundDrainTimeout.Value; |
| | | 139 | | |
| | | 140 | | return this; |
| | | 141 | | } |
| | | 142 | | } |