Struct FileMetricExporter 

pub struct FileMetricExporter { /* private fields */ }

An OpenTelemetry exporter that writes Metrics to a file on export.

Implementations

impl FileMetricExporter

pub fn new(path: PathBuf) -> Result<Self, OTelSdkError>

Creates a new FileMetricExporter that writes metrics to the specified path.

Arguments

• path - The path where metrics will be written. This can be either a file or directory path.

Behavior

• If the path points to a directory:
  • The directory must exist
  • Metrics will be written to a file named “signals.json” within that directory
• If the path points to a file:
  • If the file exists, new metrics will be appended to it (existing data is preserved)
  • If the file doesn’t exist, it will be created
  • The parent directory must exist

Errors

Returns an error if:

• The parent directory doesn’t exist
• The path points to a directory that doesn’t exist
• The user doesn’t have write permissions for the target location

Trait Implementations

impl PushMetricExporter for FileMetricExporter

fn force_flush(&self) -> OTelSdkResult

No-op implementation since metrics are written immediately in export()

fn temporality(&self) -> Temporality

Access the Temporality of the MetricExporter.

async fn export(&self, metrics: &ResourceMetrics) -> OTelSdkResult

Export serializes and transmits metric data to a receiver.

fn shutdown_with_timeout(&self, _timeout: Duration) -> OTelSdkResult

Releases any held computational resources.

fn shutdown(&self) -> Result<(), OTelSdkError>

Shutdown with the default timeout of 5 seconds.