PHP Prometheus Serializer

A PHP library for serializing to the prometheus text format.

NOTE This library does not keep state. It is intended purely as a serialization library. Therefore, there are no methods into increment or decrement values for metrics, only to set them in order to be serialized.

Installation

composer require previousnext/php-prometheus

Usage

Gauge

$gauge = new Gauge("foo", "bar", "A test gauge");
$gauge->set(100, ['baz' => 'wiz']);
$gauge->set(90, ['wobble' => 'wibble', 'bing' => 'bong']);
$gauge->set(0);

$serializer = MetricSerializerFactory::create();
$output = $serializer->serialize($gauge, 'prometheus');

Expected output:

# HELP foo_bar A test gauge
# TYPE foo_bar gauge
foo_bar{baz="wiz"} 100
foo_bar{wobble="wibble",bing="bong"} 90
foo_bar 0

Counter

$counter = new Counter("foo", "bar", "A counter for testing");
$counter->set(100, ['baz' => 'wiz']);

$serializer = MetricSerializerFactory::create();
$output = $serializer->serialize($counter, 'prometheus');

Expected output:

# HELP foo_bar A counter for testing
# TYPE foo_bar counter
foo_bar{baz="wiz"} 100

Summary

$summary = new Summary("foo", "bar", "Summary help text", 'baz');
$buckets = [0, 0.25, 0.5, 0.75, 1];
$values = [2, 4, 6, 8, 10];
$summary->setValues($buckets, $values);
$summary->setSum(54321);
$summary->setCount(212);

$serializer = MetricSerializerFactory::create();
$output = $serializer->serialize($summary, 'prometheus');

Expected output:

# HELP foo_bar Summary help text
# TYPE foo_bar summary
foo_bar{baz="0"} 2
foo_bar{baz="0.25"} 4
foo_bar{baz="0.5"} 6
foo_bar{baz="0.75"} 8
foo_bar{baz="1"} 10
foo_bar_sum 54321
foo_bar_count 212

Developing

PHP CodeSniffer

./bin/phpcs

PHPUnit

./bin/phpunit