@imskully/pm2-auto-pull/app.js

A pm2 module that automatically pulls the latest git version for your pm2 processes.

const io = require ("@pm2/io");
const pm2 = require("pm2");
const async = require("async");

let IS_FETCHING = false; // Whether we are currently fetching the latest version for all processes.
let LAST_CHECK = false; // The last time we checked for updates.

/**
 * fetchLatestVersion()
 * Fetches the latest git version for all connected pm2 processes.
 */
async function fetchLatestVersion()
{
	if (IS_FETCHING) return; // Already fetching, skip.

	log("Fetching latest version for all processes..");
	LAST_CHECK = Date.now();

	return new Promise(async (resolve, reject) => {
		// Fetch all processes.
		pm2.list((error, allProcesses) => {
			if (error) {
				console.error("[pm2-auto-pull]: Error whilst fetching process list!", error);
				IS_FETCHING = false;
				return reject(error);
			}

			// Keep track of each process we check and their outcome.
			let fetchStats = { checked: [], updated: [], skipped: [] }

			// Iterate through all processes and pull latest version.
			async.forEachLimit(allProcesses, 1, (process, next) => {
				fetchStats.checked.push(process.name);

				if (
					!process?.pm2_env || // Skip if no pm2_env available.
					process?.pm2_env?.status != "online" || // Or if the process is not online.
					!process.pm2_env?.versioning // Or if the process has no configured version control.
				) {
					fetchStats.skipped.push(process.name);
					return next();
				}

				log(`Checking updates for ${process.name}..`);
				pm2.pullAndReload(process.name, (error, metadata) => {
					if (error) return next(error); // Already up to date.

					if (metadata) log(`Successfully pulled latest version for '${process.name}'!`, true);
					fetchStats.updated.push(process.name);
					return next();
				});
			}, () => {
				// All processes have been checked.
				IS_FETCHING = false;
				log(fetchStats);
				return resolve(fetchStats);
			});
		});
	});
}

/**
 * log(message, [force = false])
 * Logs a message to the console as this module.
 * 
 * @param {String} 	message 	The message to log.
 * @param {Boolean} force 		Whether to force log the message regardless of logging setting.
 */
function log(message, force = false)
{
	if (!force && !io.getConfig()?.logging) return;
	return console.log("[pm2-auto-pull]:", message);
}

// pm2 module configuration and initialization.
io.init({
	human_info: [
		["Update Check Interval", `${io.getConfig()?.interval || 30000}ms`],
		["Last Check", (LAST_CHECK ? new Date(LAST_CHECK).toLocaleString() : "Never")],
		["Verbose Logging", io.getConfig()?.logging ? "Enabled" : "Disabled"]
	]
}).initModule({}, (error) => {
	if (error) return console.error("[pm2-auto-pull]: Failed to initialize module!", error);

	// Parse interval value.
	let FETCH_INTERVAL = parseInt(io.getConfig()?.interval); // How often to check for updates (in ms)
	if (!FETCH_INTERVAL || FETCH_INTERVAL < 1000) FETCH_INTERVAL = 30000; // Fallback to default if invalid value provided.

	pm2.connect(() => {
		setInterval(fetchLatestVersion, FETCH_INTERVAL); // Start fetching latest version every interval.
		log(`Connected to pm2 instance and now updating git every ${FETCH_INTERVAL}ms!`, true);
	});
});

// Expose pm2 action to manually trigger update check.
io.action("fetch updates", async (callback) => {
	console.log("[Fetch Updates] Manually fetching updates..");
	const fetchStats = await fetchLatestVersion().catch(() => { return callback({ status: "error" }); });

	// Prepare callback message, we only want to include stats in the response if logging is disabled to avoid duplicate output.
	let callbackMessage = { status: "success" }
	if (!io.getConfig()?.logging) callbackMessage = { ...callbackMessage, ...fetchStats };
	return callback(callbackMessage);
});