Macro prometheus_metrics

prometheus_metrics!() { /* proc-macro */ }

Define Prometheus metric families with automatic registration.

This macro generates:

• Static metric instances with proper types
• Label structs for metrics with labels
• Automatic registration with a global registry

Syntax

use metrics_macro::prometheus_metrics;
use prometheus_client::metrics::counter::Counter;

prometheus_metrics! {
    /// Documentation comment for the metric
    #[labels(label_name = String)]  // Optional labels
    static metric_name: Counter;
}

Supported Metric Types

• Counter - Monotonically increasing counter
• Gauge - Value that can go up and down

Examples

Simple Counter

use metrics_macro::prometheus_metrics;
use prometheus_client::metrics::counter::Counter;

prometheus_metrics! {
    /// Total number of requests processed
    static requests_total: Counter;
}

Labeled Gauge

use metrics_macro::prometheus_metrics;
use prometheus_client::metrics::gauge::Gauge;

prometheus_metrics! {
    /// Current memory usage by component
    #[labels(component = String, unit = String)]
    static memory_usage: Gauge;
}