NewEventCounter returns an EventCounter that counts events processed, recording them as `<processor.event>.transformations` under the given registry.

DroppedSpansStatsDiscarder removes the Transaction.DroppedSpanStats since we only use that field to process and publish metricsets.

EventCounter is a model.BatchProcessor that counts the number of events processed, recording the counts as metrics in a monitoring.Registry.

Nop is a no-op model.BatchProcessor.

Placeholder calls the underlying BatchProcessor.

SetCulprit is a model.BatchProcessor that sets or updates the culprit for RUM errors, after source mapping and identifying library frames.

SetDataStream is a model.BatchProcessor that sets the data stream for events.

SetDefaultServiceEnvironment is a transform.Processor that sets a default service.environment value for events without one already set.

SetErrorMessage is a model.BatchProcessor that sets the APMEvent.Message field for error events.

SetExcludeFromGrouping is a model.BatchProcessor that identifies stack frames to exclude from error grouping for RUM, using a configurable regular expression.

SetGroupingKey is a model.BatchProcessor that sets the grouping key for errors by hashing their stack frames.

SetHostHostname is a transform.Processor that sets the final host.name and host.hostname values, according to whether the event originated from within Kubernetes or not.

SetLibraryFrame is a model.BatchProcessor that identifies stack frames from library code for RUM, using a configurable regular expression.

SetMetricsetName is a transform.Processor that sets a name for metricsets containing well-known agent metrics, such as breakdown metrics.

SetServiceNodeName is a transform.Processor that sets the service node name value for events without one already set.

UnsetIndexDocCountField is a BatchProcessor that unsets the DocCount field on a model.APMEvent.Metricset.

Chained is a chained model.BatchProcessor, calling each of the processors in the slice in series.