@metrics/process/lib/collector-v8-heap.js

Module for collecting different process and system metrics and providing them as a metric stream

"use strict";

const Metric = require("@metrics/metric");
const v8 = require("v8");

const CollectorV8Heap = class CollectorV8Heap {
	constructor(prefix = "") {
		Object.defineProperty(this, "prefix", {
			value: prefix,
		});
	}

	get [Symbol.toStringTag]() {
		return "CollectorV8Heap";
	}

	collect(timestamp) {
		const metrics = [];

		v8.getHeapSpaceStatistics().forEach((space) => {
			const name = space.space_name.substr(0, space.space_name.indexOf("_space"));

			metrics.push(
				new Metric({
					name: `${this.prefix}nodejs_heap_space_size_total_bytes`,
					description: "Process heap space size total from node.js in bytes",
					type: 1,
					labels: [
						{
							name: "space",
							value: name,
						},
					],
					timestamp,
					value: space.space_size,
				}),
			);

			metrics.push(
				new Metric({
					name: `${this.prefix}nodejs_heap_space_size_used_bytes`,
					description: "Process heap space size used from node.js in bytes",
					type: 1,
					labels: [
						{
							name: "space",
							value: name,
						},
					],
					timestamp,
					value: space.space_used_size,
				}),
			);

			metrics.push(
				new Metric({
					name: `${this.prefix}nodejs_heap_space_size_available_bytes`,
					description: "Process heap space size available from node.js in bytes",
					type: 1,
					labels: [
						{
							name: "space",
							value: name,
						},
					],
					timestamp,
					value: space.space_available_size,
				}),
			);
		});

		return metrics;
	}
};

module.exports = CollectorV8Heap;