sentinel: Add process handling for uncaught exceptions

Author: PartMan7

src/sentinel/hotpatch.ts

@@ -47,11 +47,14 @@ export async function hotpatch(this: Sentinel, hotpatchType: HotpatchType, by: s
 			case 'sentinel': {
 				cachebust('@/sentinel/create');
 				cachebust('@/sentinel/hotpatch');
+				cachebust('@/sentinel/process');
 				await cachebustDir(fsPath('sentinel', 'registers'));
 				const newSentinel = await import('@/sentinel/create');
 				this.sentinel.close();
+				this.process.kill();
 				this.sentinel = newSentinel.create(this.emitter);
 				this.hotpatch = (await import('@/sentinel/hotpatch')).hotpatch;
+				this.process = (await import('@/sentinel/process')).processHandler();
 				break;
 			}
 

src/sentinel/index.ts

@@ -2,6 +2,7 @@ import EventEmitter from 'events';
 
 import { create } from '@/sentinel/create';
 import { hotpatch } from '@/sentinel/hotpatch';
+import { processHandler } from '@/sentinel/process';
 import { Sentinel } from '@/sentinel/types';
 import { log } from '@/utils/logger';
 
@@ -13,11 +14,12 @@ const sentinel = create(emitter);
 emitter.on('complete', (label, files) => {
 	log(`Reloaded ${label} with ${files.join(', ')}`);
 });
-
 emitter.on('error', (err, label, files) => {
 	log(`Ran into an error while reloading ${label} for ${files.join(', ')}`, err);
 });
 
-const Sentinel: Sentinel = { hotpatch, sentinel, emitter };
+const process = processHandler();
+
+const Sentinel: Sentinel = { hotpatch, sentinel, emitter, process };
 
 export default Sentinel;

src/sentinel/process.ts

@@ -0,0 +1,23 @@
+import { errorLog, log } from '@/utils/logger';
+
+export function processHandler(): { kill: () => void } {
+	function errorHandler(err: Error, origin: NodeJS.UncaughtExceptionOrigin) {
+		errorLog(err);
+		log(`Error (${err.message}) thrown (${origin})`);
+		// Everything I've read says this should exit the process
+		// Unfortunately, I like living life on the edge
+		// We stay alive!
+	}
+	function rejectionHandler(promise: unknown, reasonPromise: Promise<unknown>) {
+		reasonPromise.then(reason => errorLog(new Error(`Promise failed with reason ${reason}`)));
+	}
+	process.on('uncaughtException', errorHandler);
+	process.on('unhandledRejection', rejectionHandler);
+
+	return {
+		kill: () => {
+			process.removeListener('uncaughtException', errorHandler);
+			process.removeListener('unhandledRejection', rejectionHandler);
+		},
+	};
+}

src/sentinel/types.ts

@@ -13,7 +13,7 @@ export interface Emitter extends EventEmitter {
 	emit<K extends keyof EmitterEvents>(event: K, ...args: EmitterEvents[K]): boolean;
 	on<K extends keyof EmitterEvents>(event: K, listener: (...args: EmitterEvents[K]) => void): this;
 }
-export type Sentinel = { emitter: Emitter; sentinel: FSWatcher; hotpatch: typeof hotpatch };
+export type Sentinel = { emitter: Emitter; sentinel: FSWatcher; hotpatch: typeof hotpatch; process: { kill: () => void } };
 
 export type Register = { label: string; pattern: RegExp; reload: (filepaths: string[]) => Promise<void> | void; debounce?: number };
 export type Listener = { label: string; pattern: RegExp; reload: (filepaths: string) => Promise<void> | void };