refactor(backend): refactor ChartManagementService

packages/backend/src/core/chart/ChartManagementService.ts

@@ -1,5 +1,4 @@
 import { Injectable, Inject } from '@nestjs/common';
-import { beforeShutdown } from '@/misc/before-shutdown.js';
 
 import FederationChart from './charts/federation.js';
 import NotesChart from './charts/notes.js';
@@ -13,9 +12,13 @@ import HashtagChart from './charts/hashtag.js';
 import PerUserFollowingChart from './charts/per-user-following.js';
 import PerUserDriveChart from './charts/per-user-drive.js';
 import ApRequestChart from './charts/ap-request.js';
+import type { OnApplicationShutdown } from '@nestjs/common';
 
 @Injectable()
-export class ChartManagementService {
+export class ChartManagementService implements OnApplicationShutdown {
+	private charts;
+	private saveIntervalId: NodeJS.Timer;
+
 	constructor(
 		private federationChart: FederationChart,
 		private notesChart: NotesChart,
@@ -29,10 +32,8 @@ export class ChartManagementService {
 		private perUserFollowingChart: PerUserFollowingChart,
 		private perUserDriveChart: PerUserDriveChart,
 		private apRequestChart: ApRequestChart,
-	) {}
-
-	public async run() {
-		const charts = [
+	) {
+		this.charts = [
 			this.federationChart,
 			this.notesChart,
 			this.usersChart,
@@ -46,14 +47,21 @@ export class ChartManagementService {
 			this.perUserDriveChart,
 			this.apRequestChart,
 		];
+	}
 
+	public async run() {
 		// 20分おきにメモリ情報をDBに書き込み
-		setInterval(() => {
-			for (const chart of charts) {
+		this.saveIntervalId = setInterval(() => {
+			for (const chart of this.charts) {
 				chart.save();
 			}
 		}, 1000 * 60 * 20);
+	}
 
-		beforeShutdown(() => Promise.all(charts.map(chart => chart.save())));
+	async onApplicationShutdown(signal: string): Promise<void> {
+		clearInterval(this.saveIntervalId);
+		await Promise.all(
+			this.charts.map(chart => chart.save()),
+		);
 	}
 }

packages/backend/src/misc/before-shutdown.ts

@@ -1,94 +0,0 @@
-// https://gist.github.com/nfantone/1eaa803772025df69d07f4dbf5df7e58
-
-'use strict';
-
-/**
- * @callback BeforeShutdownListener
- * @param {string} [signalOrEvent] The exit signal or event name received on the process.
- */
-
-/**
- * System signals the app will listen to initiate shutdown.
- * @const {string[]}
- */
-const SHUTDOWN_SIGNALS = ['SIGINT', 'SIGTERM'];
-
-/**
- * Time in milliseconds to wait before forcing shutdown.
- * @const {number}
- */
-const SHUTDOWN_TIMEOUT = 15000;
-
-/**
- * A queue of listener callbacks to execute before shutting
- * down the process.
- * @type {BeforeShutdownListener[]}
- */
-const shutdownListeners: ((signalOrEvent: string) => void)[] = [];
-
-/**
- * Listen for signals and execute given `fn` function once.
- * @param  {string[]} signals System signals to listen to.
- * @param  {function(string)} fn Function to execute on shutdown.
- */
-const processOnce = (signals: string[], fn: (signalOrEvent: string) => void) => {
-	for (const sig of signals) {
-		process.once(sig, fn);
-	}
-};
-
-/**
- * Sets a forced shutdown mechanism that will exit the process after `timeout` milliseconds.
- * @param {number} timeout Time to wait before forcing shutdown (milliseconds)
- */
-const forceExitAfter = (timeout: number) => () => {
-	setTimeout(() => {
-		// Force shutdown after timeout
-		console.warn(`Could not close resources gracefully after ${timeout}ms: forcing shutdown`);
-		return process.exit(1);
-	}, timeout).unref();
-};
-
-/**
- * Main process shutdown handler. Will invoke every previously registered async shutdown listener
- * in the queue and exit with a code of `0`. Any `Promise` rejections from any listener will
- * be logged out as a warning, but won't prevent other callbacks from executing.
- * @param {string} signalOrEvent The exit signal or event name received on the process.
- */
-async function shutdownHandler(signalOrEvent: string) {
-	if (process.env.NODE_ENV === 'test') return process.exit(0);
-
-	console.warn(`Shutting down: received [${signalOrEvent}] signal`);
-
-	for (const listener of shutdownListeners) {
-		try {
-			await listener(signalOrEvent);
-		} catch (err) {
-			if (err instanceof Error) {
-				console.warn(`A shutdown handler failed before completing with: ${err.message ?? err}`);
-			}
-		}
-	}
-
-	return process.exit(0);
-}
-
-/**
- * Registers a new shutdown listener to be invoked before exiting
- * the main process. Listener handlers are guaranteed to be called in the order
- * they were registered.
- * @param {BeforeShutdownListener} listener The shutdown listener to register.
- * @returns {BeforeShutdownListener} Echoes back the supplied `listener`.
- */
-export function beforeShutdown(listener: () => void) {
-	shutdownListeners.push(listener);
-	return listener;
-}
-
-// Register shutdown callback that kills the process after `SHUTDOWN_TIMEOUT` milliseconds
-// This prevents custom shutdown handlers from hanging the process indefinitely
-processOnce(SHUTDOWN_SIGNALS, forceExitAfter(SHUTDOWN_TIMEOUT));
-
-// Register process shutdown callback
-// Will listen to incoming signal events and execute all registered handlers in the stack
-processOnce(SHUTDOWN_SIGNALS, shutdownHandler);