Metrics Name Mapping

This directory contains generic logic and configuration schemas for renaming and mapping metrics emitted by specific subprocesses before they are merged into the browser's global metrics logs.

See the design doc and the configuration schema.

Configuration

The generic mapping strategy utilizes a MetricsNameMapper class initialized with a Base-64 encoded protobuf string representing the MetricsNameMappingConfiguration.

This configuration defines a rules array in metrics_name_mapping.proto which dictates whether a strictly matching histogram string should be dropped or mapped to a new_metric_name.

The MetricsNameMapper evaluator is called dynamically by the SubprocessMetricsProvider when parsing and merging metric allocation streams from child processes.