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Manual rollover

Manual rollover gives your application explicit control over when a new backing index is created. Use it when you want to trigger rollover based on application-level events or conditions, without relying on ILM.

  • You want programmatic control over rollover timing
  • ILM is not available or too complex for your use case
  • You need to trigger rollover based on application events (deployment, config change, batch completion)
public class AppEvent
{
    [Timestamp]
    [JsonPropertyName("@timestamp")]
    public DateTimeOffset Timestamp { get; set; }

    [Keyword]
    public string EventType { get; set; }

    [Text]
    public string Message { get; set; }

    [Keyword]
    public string Environment { get; set; }
}
		
[ElasticsearchMappingContext]
[Entity<AppEvent>(
    Target = EntityTarget.DataStream,
    DataStreamType = "logs",
    DataStreamDataset = "myapp",
    DataStreamNamespace = "production"
)]
public static partial class AppEventContext;

To use manual rollover, compose a full IngestStrategy<T> that includes ManualRolloverStrategy:

var tc = AppEventContext.AppEvent.Context;
var strategy = new IngestStrategy<AppEvent>(
    tc,
    BootstrapStrategies.DataStream(),
    new DataStreamIngestStrategy<AppEvent>(
        tc.IndexStrategy?.DataStreamName
            ?? throw new InvalidOperationException("DataStreamName required"),
        "/_bulk"),
    new AlwaysCreateProvisioning(),
    new NoAliasStrategy(),
    new ManualRolloverStrategy()
);
var options = new IngestChannelOptions<AppEvent>(transport, strategy, tc);
using var channel = new IngestChannel<AppEvent>(options);

await channel.BootstrapElasticsearchAsync(BootstrapMethod.Failure);
		
// Condition-based: rollover when index is older than 7 days or larger than 50 GB
await channel.RolloverAsync(maxAge: "7d", maxSize: "50gb");

// Document count: rollover when index exceeds 10 million documents
await channel.RolloverAsync(maxDocs: 10_000_000);

// Unconditional: always create a new backing index
await channel.RolloverAsync();

Elasticsearch creates a new backing index only if at least one condition is met (or unconditionally if no conditions are specified).

// Write events continuously
logger.OnEvent += entry => channel.TryWrite(entry);

// Rollover daily via a timer or scheduler
scheduler.Daily += async () =>
{
    await channel.RolloverAsync(maxAge: "1d");
};