dependency-cruiser/src/cli/listeners/ndjson.mjs

Validate and visualize dependencies. With your rules. JavaScript, TypeScript, CoffeeScript. ES6, CommonJS, AMD.

import { randomInt } from "node:crypto";
import { EOL } from "node:os";
import { INFO, SUMMARY } from "#utl/bus.mjs";

const MICRO_SECONDS_PER_SECOND = 1_000_000;
// 2 ** 47;
const MIN_RUN_ID = 140_737_488_355_328;
// Max safe int (2 ** 48), - 1. Note: != Number.MAX_SAFE_INTEGER, which is too big for crypto.randomInt
const MAX_RUN_ID = 281_474_976_710_655;

function formatPerfLine({
	runStartTime,
	runId,
	message,
	time,
	elapsedTime,
	user,
	elapsedUser,
	system,
	elapsedSystem,
	rss,
	heapUsed,
	heapTotal,
	external,
}) {
	return (
		JSON.stringify({
			runStartTime,
			runId,
			message,
			time: Math.round(time * MICRO_SECONDS_PER_SECOND),
			elapsedTime: Math.round(elapsedTime * MICRO_SECONDS_PER_SECOND),
			user,
			elapsedUser,
			system,
			elapsedSystem,
			rss,
			heapUsed,
			heapTotal,
			external,
		}) + EOL
	);
}

function getProgressLine(pMessage, pState, pLevel, pMaxLevel) {
	let lReturnValue = "";

	if (pLevel <= pMaxLevel) {
		const lTime = process.uptime();
		const { user, system } = process.cpuUsage();
		const { rss, heapTotal, heapUsed, external } = process.memoryUsage();
		const lStats = {
			runStartTime: pState.runStartTime,
			runId: pState.runId,
			message: pState.previousMessage,
			time: lTime,
			elapsedTime: lTime - pState.previousTime,
			user,
			elapsedUser: user - pState.previousUserUsage,
			system,
			elapsedSystem: system - pState.previousSystemUsage,
			rss,
			heapUsed,
			heapTotal,
			external,
		};

		pState.previousMessage = pMessage;
		pState.previousTime = lTime;
		pState.previousUserUsage = user;
		pState.previousSystemUsage = system;

		lReturnValue = formatPerfLine(lStats);
	}
	return lReturnValue;
}

function getProgressWriter(pStream, pState, pMaxLevel) {
	return (pMessage, pOptions) => {
		const lOptions = { level: SUMMARY, ...(pOptions || {}) };

		pStream.write(getProgressLine(pMessage, pState, lOptions.level, pMaxLevel));
	};
}

export default function setUpNDJSONListener(
	pEventEmitter,
	pMaxLevel = INFO,
	pStream = process.stderr,
) {
	let lState = {
		runStartTime: new Date(Date.now()).toISOString(),
		runId: randomInt(MIN_RUN_ID, MAX_RUN_ID),
		previousMessage: "startup: nodejs loading",
		previousTime: 0,
		previousUserUsage: 0,
		previousSystemUsage: 0,
	};

	pEventEmitter.on("progress", getProgressWriter(pStream, lState, pMaxLevel));

	pEventEmitter.on("end", () => {
		pStream.end();
	});
}