Summary

We are using changestream using c# mongodb driver to do some realtime work. We received an error randomly after connection to the events.

$Index was outside the bounds of the array.

var options = new ChangeStreamOptions { ResumeAfter = resumeToken, BatchSize = 5 };

CancellationTokenSource cancelTokenSource = new CancellationTokenSource();
CancellationToken token = cancelTokenSource.Token;

try {
  using(var cursor = await mongoclient.WatchAsync(pipeline, options, cancellationToken: token)) {
    await cursor.ForEachAsync(async change =>

, cancellationToken: token);
  }
} catch (Exception ex) {

}

On this line 109 await cursor.ForEachAsync we receive this error. This happens after sometime like 8,9 hours every time.  Sharing the stacktrace

at Microsoft.Extensions.Logging.LogValuesFormatter.GetValue(Object[] values, Int32 index) at Microsoft.Extensions.Logging.FormattedLogValues.GetEnumerator()+MoveNext() at Serilog.Extensions.Logging.SerilogLogger.Log[TState](LogLevel logLevel, EventId eventId, TState state, Exception exception, Func`3 formatter) at Microsoft.Extensions.Logging.Logger`1.Microsoft.Extensions.Logging.ILogger.Log[TState](LogLevel logLevel, EventId eventId, TState state, Exception exception, Func`3 formatter) at Microsoft.Extensions.Logging.LoggerExtensions.Log(ILogger logger, LogLevel logLevel, EventId eventId, Exception exception, String message, Object[] args) at SyncServer.Services.MultiDatabaseChangeStreamManager.<>cDisplayClass9_0.<<StartChangeStreams>b6>d.MoveNext() in /app/jenkins/workspace/flecx-prod-changestream/src/Host/SyncServer/Services/MultiDatabaseChangeStreamManager.cs:line 167 — End of stack trace from previous location — at MongoDB.Driver.IAsyncCursorExtensions.ForEachAsync[TDocument](IAsyncCursor`1 source, Func`3 processor, CancellationToken cancellationToken) at SyncServer.Services.MultiDatabaseChangeStreamManager.StartChangeStreams() in /app/jenkins/workspace/flecx-prod-changestream/src/Host/SyncServer/Services/MultiDatabaseChangeStreamManager.cs:line 109