Module metrics 

Prometheus metrics counters, histograms, gauges and tracing initialisation Prometheus metrics for stygian pipelines.

Provides a process-wide MetricsRegistry that tracks:

• Counters: requests, errors, cache hits/misses
• Histograms: request duration, pipeline execution time
• Gauges: active workers, queue depth, circuit-breaker state

Example

use stygian_graph::application::metrics::{MetricsRegistry, MetricEvent};

let registry = MetricsRegistry::new();
registry.record(MetricEvent::RequestStarted { service: "http".into() });
registry.record(MetricEvent::RequestCompleted {
    service: "http".into(),
    duration_ms: 142,
    success: true,
});

let snapshot = registry.snapshot();
assert_eq!(snapshot.requests_total, 1);
assert_eq!(snapshot.errors_total, 0);

Structs

MetricsRegistry

Thread-safe registry for all pipeline metrics.

MetricsSnapshot

Point-in-time snapshot of all metric counters.

TracingInit

Tracing initialisation configuration.

Enums

LogFormat

Log output format

MetricEvent

An observable event emitted by the pipeline engine.

Functions

global_metrics

Process-wide global MetricsRegistry instance.