ez-php/metrics

Prometheus metrics endpoint for the ez-php framework.

Exposes a /metrics route in the Prometheus text exposition format. Supports the three standard Prometheus metric types: Counter, Gauge, and Histogram.

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Installation

composer require ez-php/metrics

Register the provider in provider/modules.php:

\EzPhp\Metrics\MetricsServiceProvider::class,

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Usage

Counter — monotonically increasing

use EzPhp\Metrics\Metrics;

Metrics::counter('http_requests_total', 'Total HTTP requests')
    ->inc(['method' => 'GET', 'status' => '200']);

Metrics::counter('bytes_sent_total', 'Total bytes sent')
    ->incBy(1024.0);

Gauge — current value (can increase or decrease)

Metrics::gauge('memory_usage_bytes', 'Current memory usage')
    ->set((float) memory_get_usage());

Metrics::gauge('active_connections', 'Active connections')
    ->inc();

Metrics::gauge('queue_depth', 'Queue depth')
    ->dec(['queue' => 'default']);

Histogram — distributions and latency

$start = microtime(true);
// ... handle request ...
Metrics::histogram('request_duration_seconds', 'Request duration in seconds')
    ->observe(microtime(true) - $start, ['route' => '/api/users']);

Custom bucket boundaries:

Metrics::histogram('response_size_bytes', 'Response size', [100, 1000, 10000, 100000])
    ->observe((float) strlen($responseBody));

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/metrics endpoint

MetricsServiceProvider registers GET /metrics automatically. The response body is the full Prometheus text exposition format output:

# HELP http_requests_total Total HTTP requests
# TYPE http_requests_total counter
http_requests_total{method="GET",status="200"} 42

# HELP request_duration_seconds Request duration in seconds
# TYPE request_duration_seconds histogram
request_duration_seconds_bucket{route="/api/users",le="0.005"} 0
...
request_duration_seconds_bucket{route="/api/users",le="+Inf"} 5
request_duration_seconds_count{route="/api/users"} 5
request_duration_seconds_sum{route="/api/users"} 1.23

Content-Type: text/plain; version=0.0.4; charset=utf-8

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Security

The /metrics endpoint is unprotected by default. To restrict access, apply middleware in your route definition or via global middleware in your application.

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Relation to ez-php/health

Module	Purpose
ez-php/health	Liveness check — is the service up?
ez-php/metrics	Time-series data — counters, gauges, histograms for alerting and dashboards

Both are complementary production-observability tools.

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License

MIT