| | | 1 | | using Microsoft.Extensions.Logging; |
| | | 2 | | using System.Text.Json; |
| | | 3 | | using System.Text.Json.Nodes; |
| | | 4 | | using System.Threading.Channels; |
| | | 5 | | |
| | | 6 | | namespace AsyncResponse.Transports; |
| | | 7 | | |
| | | 8 | | // Shared source for the database-backed worker transports (PostgreSQL, SQL Server, MongoDB), |
| | | 9 | | // mirroring src/Channels/Shared/DbChannelShared.cs: each transport csproj pulls this file in via |
| | | 10 | | // <Compile Include="..\Shared\DbTransportShared.cs" />, so the base class compiles INTO each |
| | | 11 | | // provider assembly against that provider's concrete seam types. The seam is bound per project |
| | | 12 | | // with global using aliases (declared at the top of the provider's MessageDispatcher file): |
| | | 13 | | // |
| | | 14 | | // DbTransportOptions -> the provider's transport options (e.g. PostgreSqlAsyncResponseTransportOptions) |
| | | 15 | | // DbSubscriberOptions -> the provider's subscriber options (e.g. PostgreSqlSubscriberOptions) |
| | | 16 | | // DbTransportDelivery -> the provider's claimed-delivery type (e.g. PostgreSqlTransportDelivery) |
| | | 17 | | // DbSubscriberRole -> the provider's subscriber-role enum |
| | | 18 | | // DbAckMode -> the provider's ack-mode enum |
| | | 19 | | // DbTransportOptionsValidator -> the provider's static options validator |
| | | 20 | | // DbBackgroundFailureContext -> the provider's OnBackgroundFailure context type |
| | | 21 | | // |
| | | 22 | | // Because the aliases resolve to concrete sealed types at compile time, delivery calls stay |
| | | 23 | | // direct — no interface dispatch on the per-message path. The only provider-specific inputs are |
| | | 24 | | // three display strings supplied by the derived constructor: the provider name rendered into log |
| | | 25 | | // messages, the queue-item noun ("row"/"document"), and the lowercase telemetry tag. Rendered log |
| | | 26 | | // output and activity tags are byte-identical to the pre-extraction per-provider sources. |
| | | 27 | | |
| | | 28 | | /// <summary> |
| | | 29 | | /// Applies acknowledgement, redelivery, and dead-letter policy to database transport deliveries: |
| | | 30 | | /// ack-after-handler with fenced lease renewal, opt-in early ACK behind a bounded in-process |
| | | 31 | | /// queue with drain-on-dispose, attempt-capped dead-lettering, and the consumer receive span. |
| | | 32 | | /// Derived dispatchers supply only the provider display name, queue-item noun, and telemetry tag. |
| | | 33 | | /// </summary> |
| | | 34 | | internal abstract class DbMessageDispatcherBase : IAsyncDisposable |
| | | 35 | | { |
| | | 36 | | private readonly Func<DbTransportDelivery, CancellationToken, Task> _handler; |
| | | 37 | | private readonly DbTransportOptions _options; |
| | | 38 | | private readonly DbSubscriberOptions _subscriberOptions; |
| | | 39 | | private readonly ILogger _logger; |
| | | 40 | | private readonly DbSubscriberRole _role; |
| | | 41 | | private readonly string _providerName; |
| | | 42 | | private readonly string _unitNoun; |
| | | 43 | | private readonly string _receiveActivityName; |
| | | 44 | | private readonly string _transportTag; |
| | | 45 | | private readonly string _roleTagName; |
| | | 46 | | private readonly string _ackModeTagName; |
| | | 47 | | |
| | | 48 | | private readonly Channel<DbTransportDelivery>? _backgroundQueue; |
| | | 49 | | private readonly Task[]? _backgroundWorkers; |
| | | 50 | | private readonly CancellationTokenSource? _backgroundCts; |
| | | 51 | | |
| | | 52 | | protected DbMessageDispatcherBase( |
| | | 53 | | Func<DbTransportDelivery, CancellationToken, Task> handler, |
| | | 54 | | DbTransportOptions options, |
| | | 55 | | DbSubscriberOptions subscriberOptions, |
| | | 56 | | ILogger logger, |
| | | 57 | | DbSubscriberRole role, |
| | | 58 | | string providerName, |
| | | 59 | | string unitNoun, |
| | | 60 | | string telemetryName) |
| | | 61 | | { |
| | | 62 | | DbTransportOptionsValidator.ValidateSubscriber(options, subscriberOptions, role.ToString()); |
| | | 63 | | |
| | | 64 | | _handler = handler; |
| | | 65 | | _options = options; |
| | | 66 | | _subscriberOptions = subscriberOptions; |
| | | 67 | | _logger = logger; |
| | | 68 | | _role = role; |
| | | 69 | | _providerName = providerName; |
| | | 70 | | _unitNoun = unitNoun; |
| | | 71 | | _receiveActivityName = $"asyncresponse.{telemetryName}.receive"; |
| | | 72 | | _transportTag = telemetryName; |
| | | 73 | | _roleTagName = $"asyncresponse.{telemetryName}.role"; |
| | | 74 | | _ackModeTagName = $"asyncresponse.{telemetryName}.ack_mode"; |
| | | 75 | | |
| | | 76 | | if (subscriberOptions.AckMode is DbAckMode.AckAfterEnqueue) |
| | | 77 | | { |
| | | 78 | | _backgroundQueue = Channel.CreateBounded<DbTransportDelivery>(new BoundedChannelOptions(subscriberOptions.Ba |
| | | 79 | | { |
| | | 80 | | SingleReader = false, |
| | | 81 | | SingleWriter = true, |
| | | 82 | | FullMode = BoundedChannelFullMode.Wait |
| | | 83 | | }); |
| | | 84 | | _backgroundCts = new CancellationTokenSource(); |
| | | 85 | | _backgroundWorkers = new Task[subscriberOptions.BackgroundWorkerCount]; |
| | | 86 | | for (var i = 0; i < _backgroundWorkers.Length; i++) |
| | | 87 | | _backgroundWorkers[i] = Task.Run(() => BackgroundWorkerLoopAsync(_backgroundCts.Token)); |
| | | 88 | | } |
| | | 89 | | } |
| | | 90 | | |
| | | 91 | | /// <summary>Handles one claimed queue item.</summary> |
| | | 92 | | public async Task HandleAsync(DbTransportDelivery delivery, CancellationToken cancellationToken) |
| | | 93 | | { |
| | | 94 | | if (_subscriberOptions.AckMode is DbAckMode.AckAfterEnqueue) |
| | | 95 | | { |
| | | 96 | | await HandleEarlyAckAsync(delivery).ConfigureAwait(false); |
| | | 97 | | return; |
| | | 98 | | } |
| | | 99 | | |
| | | 100 | | try |
| | | 101 | | { |
| | | 102 | | // While the handler runs, a fenced heartbeat keeps extending the claim's lease at |
| | | 103 | | // LockTimeout/2 cadence so a slow handler does not let the lock lapse and a competing |
| | | 104 | | // subscriber re-claim (and duplicate-process) the queue item. |
| | | 105 | | using var renewalCancellation = CancellationTokenSource.CreateLinkedTokenSource(cancellationToken); |
| | | 106 | | var renewalTask = RenewLeaseLoopAsync(delivery, renewalCancellation.Token); |
| | | 107 | | try |
| | | 108 | | { |
| | | 109 | | await ExecuteHandlerAsync(delivery, cancellationToken).ConfigureAwait(false); |
| | | 110 | | } |
| | | 111 | | finally |
| | | 112 | | { |
| | | 113 | | renewalCancellation.Cancel(); |
| | | 114 | | await renewalTask.ConfigureAwait(false); |
| | | 115 | | } |
| | | 116 | | |
| | | 117 | | await delivery.AckAsync().ConfigureAwait(false); |
| | | 118 | | } |
| | | 119 | | catch (Exception ex) |
| | | 120 | | { |
| | | 121 | | await HandleFailureAsync(delivery, ex, cancellationToken).ConfigureAwait(false); |
| | | 122 | | } |
| | | 123 | | } |
| | | 124 | | |
| | | 125 | | private async Task RenewLeaseLoopAsync(DbTransportDelivery delivery, CancellationToken cancellationToken) |
| | | 126 | | { |
| | | 127 | | var interval = TimeSpan.FromTicks(Math.Max(1, _options.LockTimeout.Ticks / 2)); |
| | | 128 | | try |
| | | 129 | | { |
| | | 130 | | while (true) |
| | | 131 | | { |
| | | 132 | | await Task.Delay(interval, cancellationToken).ConfigureAwait(false); |
| | | 133 | | |
| | | 134 | | bool renewed; |
| | | 135 | | try |
| | | 136 | | { |
| | | 137 | | renewed = await delivery.RenewAsync().ConfigureAwait(false); |
| | | 138 | | } |
| | | 139 | | catch (Exception ex) |
| | | 140 | | { |
| | | 141 | | _logger.LogWarning( |
| | | 142 | | ex, |
| | | 143 | | "Failed to renew the lease of {Provider} message {MessageId} on queue {Queue} ({Role}); retrying |
| | | 144 | | _providerName, |
| | | 145 | | delivery.Id, |
| | | 146 | | delivery.Queue, |
| | | 147 | | _role); |
| | | 148 | | continue; |
| | | 149 | | } |
| | | 150 | | |
| | | 151 | | if (!renewed) |
| | | 152 | | { |
| | | 153 | | // The lock_id fence no longer matches: the lease expired and another subscriber |
| | | 154 | | // claimed the queue item. Stop renewing; the fenced ack/NAK will no-op for this |
| | | 155 | | // claim. |
| | | 156 | | _logger.LogWarning( |
| | | 157 | | "Lease of {Provider} message {MessageId} on queue {Queue} ({Role}) was lost; another subscriber |
| | | 158 | | _providerName, |
| | | 159 | | delivery.Id, |
| | | 160 | | delivery.Queue, |
| | | 161 | | _role); |
| | | 162 | | return; |
| | | 163 | | } |
| | | 164 | | } |
| | | 165 | | } |
| | | 166 | | catch (OperationCanceledException) |
| | | 167 | | { |
| | | 168 | | // The handler finished or the subscriber is stopping. |
| | | 169 | | } |
| | | 170 | | } |
| | | 171 | | |
| | | 172 | | // Single choke point for handler execution so both ACK modes emit the consumer receive span. |
| | | 173 | | private async Task ExecuteHandlerAsync(DbTransportDelivery delivery, CancellationToken cancellationToken) |
| | | 174 | | { |
| | | 175 | | using var activity = AsyncResponseDiagnostics.StartActivity( |
| | | 176 | | _receiveActivityName, |
| | | 177 | | System.Diagnostics.ActivityKind.Consumer); |
| | | 178 | | activity?.SetTag("asyncresponse.transport", _transportTag); |
| | | 179 | | activity?.SetTag(_roleTagName, _role.ToString()); |
| | | 180 | | activity?.SetTag(_ackModeTagName, _subscriberOptions.AckMode.ToString()); |
| | | 181 | | activity?.SetTag("messaging.system", _transportTag); |
| | | 182 | | activity?.SetTag("messaging.destination.name", delivery.Queue); |
| | | 183 | | activity?.SetTag("messaging.message.id", delivery.Id.ToString()); |
| | | 184 | | activity?.SetTag("messaging.message.delivery_attempt", delivery.Attempt); |
| | | 185 | | |
| | | 186 | | if (delivery.Headers.TryGetValue(_options.CorrelationIdHeader, out var correlationId)) |
| | | 187 | | AsyncResponseDiagnostics.SetCorrelationId(activity, correlationId); |
| | | 188 | | |
| | | 189 | | try |
| | | 190 | | { |
| | | 191 | | await _handler(delivery, cancellationToken).ConfigureAwait(false); |
| | | 192 | | } |
| | | 193 | | catch (Exception ex) |
| | | 194 | | { |
| | | 195 | | AsyncResponseDiagnostics.SetError(activity, ex); |
| | | 196 | | throw; |
| | | 197 | | } |
| | | 198 | | } |
| | | 199 | | |
| | | 200 | | private async Task HandleEarlyAckAsync(DbTransportDelivery delivery) |
| | | 201 | | { |
| | | 202 | | if (_backgroundQueue!.Writer.TryWrite(delivery)) |
| | | 203 | | { |
| | | 204 | | await delivery.AckAsync().ConfigureAwait(false); |
| | | 205 | | } |
| | | 206 | | else |
| | | 207 | | { |
| | | 208 | | _logger.LogDebug("Background queue full for {Provider} {Role}; releasing {Unit} for redelivery.", _providerN |
| | | 209 | | await delivery.NakAsync(_subscriberOptions.RedeliveryDelay).ConfigureAwait(false); |
| | | 210 | | } |
| | | 211 | | } |
| | | 212 | | |
| | | 213 | | private async Task BackgroundWorkerLoopAsync(CancellationToken cancellationToken) |
| | | 214 | | { |
| | | 215 | | // Token-less ReadAllAsync: on shutdown the queue is completed and fully drained, so every |
| | | 216 | | // already-ACKed queue item is attempted (with the drain token once the drain budget lapses) |
| | | 217 | | // instead of being silently dropped; each failure is dead-lettered and surfaced below. |
| | | 218 | | await foreach (var delivery in _backgroundQueue!.Reader.ReadAllAsync().ConfigureAwait(false)) |
| | | 219 | | { |
| | | 220 | | try |
| | | 221 | | { |
| | | 222 | | await ExecuteHandlerAsync(delivery, cancellationToken).ConfigureAwait(false); |
| | | 223 | | } |
| | | 224 | | catch (Exception ex) |
| | | 225 | | { |
| | | 226 | | _logger.LogError(ex, "{Provider} background handler failed for {Role} on queue {Queue} after early ACK." |
| | | 227 | | if (!await delivery.DeadLetterAsync(ex, false, CancellationToken.None).ConfigureAwait(false)) |
| | | 228 | | { |
| | | 229 | | _logger.LogError( |
| | | 230 | | "Failed to dead-letter already-ACKed {Provider} message {MessageId} on queue {Queue} ({Role}); t |
| | | 231 | | _providerName, |
| | | 232 | | delivery.Id, |
| | | 233 | | delivery.Queue, |
| | | 234 | | _role); |
| | | 235 | | } |
| | | 236 | | |
| | | 237 | | await InvokeBackgroundFailureAsync(delivery, ex).ConfigureAwait(false); |
| | | 238 | | } |
| | | 239 | | } |
| | | 240 | | } |
| | | 241 | | |
| | | 242 | | private async Task HandleFailureAsync(DbTransportDelivery delivery, Exception exception, CancellationToken cancellat |
| | | 243 | | { |
| | | 244 | | var maxAttempts = _subscriberOptions.MaxDeliveryAttempts; |
| | | 245 | | if (maxAttempts > 0 && delivery.Attempt >= maxAttempts) |
| | | 246 | | { |
| | | 247 | | _logger.LogError( |
| | | 248 | | exception, |
| | | 249 | | "{Provider} message on queue {Queue} ({Role}) failed after {Attempts} attempts; dead-lettering.", |
| | | 250 | | _providerName, |
| | | 251 | | delivery.Queue, |
| | | 252 | | _role, |
| | | 253 | | delivery.Attempt); |
| | | 254 | | |
| | | 255 | | var deadLettered = await delivery.DeadLetterAsync(exception, true, cancellationToken).ConfigureAwait(false); |
| | | 256 | | if (!deadLettered) |
| | | 257 | | { |
| | | 258 | | _logger.LogWarning(exception, "{Provider} dead-letter publish failed for queue {Queue} ({Role}); releasi |
| | | 259 | | await delivery.NakAsync(_subscriberOptions.RedeliveryDelay).ConfigureAwait(false); |
| | | 260 | | } |
| | | 261 | | } |
| | | 262 | | else |
| | | 263 | | { |
| | | 264 | | _logger.LogWarning( |
| | | 265 | | exception, |
| | | 266 | | "{Provider} message on queue {Queue} ({Role}) failed on attempt {Attempt}; releasing for redelivery.", |
| | | 267 | | _providerName, |
| | | 268 | | delivery.Queue, |
| | | 269 | | _role, |
| | | 270 | | delivery.Attempt); |
| | | 271 | | await delivery.NakAsync(_subscriberOptions.RedeliveryDelay).ConfigureAwait(false); |
| | | 272 | | } |
| | | 273 | | } |
| | | 274 | | |
| | | 275 | | private async Task InvokeBackgroundFailureAsync(DbTransportDelivery delivery, Exception exception) |
| | | 276 | | { |
| | | 277 | | if (_subscriberOptions.OnBackgroundFailure is null) |
| | | 278 | | return; |
| | | 279 | | |
| | | 280 | | try |
| | | 281 | | { |
| | | 282 | | delivery.Headers.TryGetValue(_options.CorrelationIdHeader, out var correlationId); |
| | | 283 | | var context = new DbBackgroundFailureContext(delivery.Queue, _role.ToString(), delivery.Attempt, correlation |
| | | 284 | | await _subscriberOptions.OnBackgroundFailure(context).ConfigureAwait(false); |
| | | 285 | | } |
| | | 286 | | catch (Exception ex) |
| | | 287 | | { |
| | | 288 | | _logger.LogError(ex, "{Provider} OnBackgroundFailure callback threw for {Role}.", _providerName, _role); |
| | | 289 | | } |
| | | 290 | | } |
| | | 291 | | |
| | | 292 | | /// <inheritdoc /> |
| | | 293 | | public async ValueTask DisposeAsync() |
| | | 294 | | { |
| | | 295 | | if (_backgroundQueue is null) |
| | | 296 | | return; |
| | | 297 | | |
| | | 298 | | _backgroundQueue.Writer.TryComplete(); |
| | | 299 | | try |
| | | 300 | | { |
| | | 301 | | await Task.WhenAll(_backgroundWorkers!).WaitAsync(_subscriberOptions.BackgroundDrainTimeout).ConfigureAwait( |
| | | 302 | | _backgroundCts!.Dispose(); |
| | | 303 | | } |
| | | 304 | | catch (TimeoutException) |
| | | 305 | | { |
| | | 306 | | _logger.LogWarning("{Provider} background handlers for {Role} did not drain within {Timeout}.", _providerNam |
| | | 307 | | await _backgroundCts!.CancelAsync().ConfigureAwait(false); |
| | | 308 | | |
| | | 309 | | // The workers are still running and observe _backgroundCts.Token inside ReadAllAsync, so disposing |
| | | 310 | | // it now would throw ObjectDisposedException inside them. Dispose once they actually finish, off |
| | | 311 | | // the shutdown path, so the source is not leaked either. |
| | | 312 | | _ = Task.WhenAll(_backgroundWorkers!).ContinueWith( |
| | | 313 | | _ => _backgroundCts.Dispose(), |
| | | 314 | | CancellationToken.None, |
| | | 315 | | TaskContinuationOptions.ExecuteSynchronously, |
| | | 316 | | TaskScheduler.Default); |
| | | 317 | | } |
| | | 318 | | catch (Exception ex) |
| | | 319 | | { |
| | | 320 | | // WhenAll only completes once every worker has finished, so the source is safe to dispose here. |
| | | 321 | | _logger.LogDebug(ex, "{Provider} background worker drain for {Role} ended with an error.", _providerName, _r |
| | | 322 | | _backgroundCts!.Dispose(); |
| | | 323 | | } |
| | | 324 | | } |
| | | 325 | | } |
| | | 326 | | |
| | | 327 | | /// <summary> |
| | | 328 | | /// Extracts the AsyncResponse correlation id from the queue item's metadata first, then from the |
| | | 329 | | /// JSON response body via configured paths. Shared verbatim by the three database transports — |
| | | 330 | | /// the header name and JSON paths both come from the aliased options type. |
| | | 331 | | /// </summary> |
| | | 332 | | internal static class DbCorrelationIdExtractor |
| | | 333 | | { |
| | | 334 | | public static string? Extract( |
| | | 335 | | IReadOnlyDictionary<string, string>? headers, |
| | | 336 | | string messageJson, |
| | | 337 | | DbTransportOptions options) |
| | | 338 | | { |
| | 3 | 339 | | var headerName = DbTransportOptionsValidator.Required(options.CorrelationIdHeader, nameof(options.CorrelationIdH |
| | 3 | 340 | | if (headers is not null && headers.TryGetValue(headerName, out var headerValue) && !string.IsNullOrWhiteSpace(he |
| | 3 | 341 | | return headerValue; |
| | | 342 | | |
| | 3 | 343 | | var jsonPaths = options.CorrelationIdJsonPaths; |
| | 3 | 344 | | if (jsonPaths is null || jsonPaths.Length == 0 || string.IsNullOrWhiteSpace(messageJson)) |
| | 3 | 345 | | return null; |
| | | 346 | | |
| | | 347 | | JsonNode? root; |
| | | 348 | | try |
| | | 349 | | { |
| | 3 | 350 | | root = JsonNode.Parse(messageJson); |
| | 3 | 351 | | } |
| | 3 | 352 | | catch (JsonException) |
| | | 353 | | { |
| | 3 | 354 | | return null; |
| | | 355 | | } |
| | | 356 | | |
| | 3 | 357 | | if (root is null) |
| | 3 | 358 | | return null; |
| | | 359 | | |
| | 3 | 360 | | foreach (var path in jsonPaths) |
| | | 361 | | { |
| | 3 | 362 | | var value = TryReadPath(root, path); |
| | 3 | 363 | | if (!string.IsNullOrWhiteSpace(value)) |
| | 3 | 364 | | return value; |
| | | 365 | | } |
| | | 366 | | |
| | 3 | 367 | | return null; |
| | 3 | 368 | | } |
| | | 369 | | |
| | | 370 | | private static string? TryReadPath(JsonNode root, string path) |
| | | 371 | | { |
| | 3 | 372 | | if (string.IsNullOrWhiteSpace(path)) |
| | 3 | 373 | | return null; |
| | | 374 | | |
| | 3 | 375 | | var current = root; |
| | 3 | 376 | | foreach (var segment in path.Split('.', StringSplitOptions.RemoveEmptyEntries | StringSplitOptions.TrimEntries)) |
| | | 377 | | { |
| | 3 | 378 | | current = UnwrapJsonString(current); |
| | 3 | 379 | | if (current is not JsonObject obj) |
| | 3 | 380 | | return null; |
| | | 381 | | |
| | 3 | 382 | | current = TryGetProperty(obj, segment); |
| | 3 | 383 | | if (current is null) |
| | 3 | 384 | | return null; |
| | | 385 | | } |
| | | 386 | | |
| | 3 | 387 | | current = UnwrapJsonString(current); |
| | 3 | 388 | | return current switch |
| | 3 | 389 | | { |
| | 3 | 390 | | JsonValue value when value.TryGetValue<string>(out var s) => s, |
| | 3 | 391 | | JsonValue value => value.ToString(), |
| | 3 | 392 | | _ => null |
| | 3 | 393 | | }; |
| | | 394 | | } |
| | | 395 | | |
| | | 396 | | private static JsonNode? TryGetProperty(JsonObject obj, string name) |
| | | 397 | | { |
| | 3 | 398 | | if (obj.TryGetPropertyValue(name, out var exact)) |
| | 3 | 399 | | return exact; |
| | | 400 | | |
| | 3 | 401 | | foreach (var property in obj) |
| | | 402 | | { |
| | 2 | 403 | | if (string.Equals(property.Key, name, StringComparison.OrdinalIgnoreCase)) |
| | 2 | 404 | | return property.Value; |
| | | 405 | | } |
| | | 406 | | |
| | 2 | 407 | | return null; |
| | 3 | 408 | | } |
| | | 409 | | |
| | | 410 | | private static JsonNode? UnwrapJsonString(JsonNode? node) |
| | | 411 | | { |
| | 3 | 412 | | if (node is not JsonValue value || !value.TryGetValue<string>(out var text)) |
| | 3 | 413 | | return node; |
| | | 414 | | |
| | 3 | 415 | | var trimmed = text.AsSpan().TrimStart(); |
| | 3 | 416 | | if (trimmed.Length == 0 || (trimmed[0] != '{' && trimmed[0] != '[')) |
| | 3 | 417 | | return node; |
| | | 418 | | |
| | | 419 | | try |
| | | 420 | | { |
| | 2 | 421 | | return JsonNode.Parse(text); |
| | | 422 | | } |
| | 2 | 423 | | catch (JsonException) |
| | | 424 | | { |
| | 2 | 425 | | return node; |
| | | 426 | | } |
| | 2 | 427 | | } |
| | | 428 | | } |