Struct MetricsLogObserver 

pub struct MetricsLogObserver { /* private fields */ }

Collects (and tracing-logs) every MetricsData flowing on Frame::Metrics — a pure, network-free metrics observer. Mirrors pipecat’s MetricsLogObserver: it watches the push hook, de-dupes by frame id, and records each metric with its timestamp so tests (and metric exporters) can read TTFB/RTF/processing/usage semantics without a live sink.

“RTF” (real-time factor) is derived, not a first-class metric: it is processing_seconds / audio_seconds for a stage that reports both — see MetricsLogObserver::real_time_factor.

Implementations

impl MetricsLogObserver

pub fn new() -> Self

A fresh collector.

pub fn metrics(&self) -> Vec<ObservedMetric>

Every metric observed so far, in observation order.

pub fn ttfb_seconds(&self, processor: &str) -> Option<f64>

The most-recent TTFB (seconds) reported by processor, if any. TTFB is the user-stop → first-output latency a service measures via Link::start_ttfb / Link::stop_ttfb.

pub fn processing_seconds(&self, processor: &str) -> Option<f64>

The most-recent processing time (seconds) reported by processor.

pub fn real_time_factor( &self, processor: &str, audio_seconds: f64, ) -> Option<f64>

Real-time factor for processor: its last processing-time divided by audio_seconds of audio it processed. RTF < 1 ⇒ faster than real time. Returns None if no processing metric was seen or audio_seconds == 0.

pub fn total_llm_tokens(&self) -> u64

Total LLM tokens summed across every LlmUsage metric seen.

Trait Implementations

impl Default for MetricsLogObserver

fn default() -> Self

Returns the “default value” for a type.

impl FrameObserver for MetricsLogObserver

fn on_push<'life0, 'life1, 'life2, 'async_trait>( &'life0 self, e: &'life1 FramePushEvent<'life2>, ) -> Pin<Box<dyn Future<Output = ()> + Send + 'async_trait>>

where Self: 'async_trait, 'life0: 'async_trait, 'life1: 'async_trait, 'life2: 'async_trait,

A frame was pushed source→destination (base_observer.py:91).

fn on_process<'life0, 'life1, 'life2, 'async_trait>( &'life0 self, _e: &'life1 FrameEvent<'life2>, ) -> Pin<Box<dyn Future<Output = ()> + Send + 'async_trait>>

where Self: 'async_trait, 'life0: 'async_trait, 'life1: 'async_trait, 'life2: 'async_trait,

A processor is about to handle a frame (base_observer.py:79).

fn on_pipeline_started<'life0, 'async_trait>( &'life0 self, ) -> Pin<Box<dyn Future<Output = ()> + Send + 'async_trait>>

where Self: 'async_trait, 'life0: 'async_trait,

The pipeline finished starting (base_observer.py:103).