Blame · logger.ts

b69ab31	1	/**
b69ab31	2	* Copyright (c) Meta Platforms, Inc. and affiliates.
b69ab31	3	*
b69ab31	4	* This source code is licensed under the MIT license found in the
b69ab31	5	* LICENSE file in the root directory of this source tree.
b69ab31	6	*/
b69ab31	7
b69ab31	8	export type Level = 'log' \| 'info' \| 'warn' \| 'error';
b69ab31	9
b69ab31	10	const tzOptions: Intl.DateTimeFormatOptions & {
b69ab31	11	// This is an ES2021 feature which is not properly reflected in the types but is available. TODO: update target to ES2021 to fix this.
b69ab31	12	// See https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Intl/DateTimeFormat/DateTimeFormat#fractionalseconddigits
b69ab31	13	fractionalSecondDigits: 1 \| 2 \| 3;
b69ab31	14	} = {
b69ab31	15	timeZoneName: 'short',
b69ab31	16	// Show millisecond resolution for extra timing information in the logs
b69ab31	17	fractionalSecondDigits: 3,
b69ab31	18	// After setting fractionalSecondDigits, it requires setting all fields we want printed to 'numeric'.
b69ab31	19	year: 'numeric',
b69ab31	20	month: 'numeric',
b69ab31	21	day: 'numeric',
b69ab31	22	hour: 'numeric',
b69ab31	23	minute: 'numeric',
b69ab31	24	second: 'numeric',
b69ab31	25	};
b69ab31	26
b69ab31	27	/** Standardized logging interface for the server.
b69ab31	28	* Format: [YYY-MM-DD HH:MM:SS,MILLISECONDS TIMEZONE] [LEVEL] your message here
b69ab31	29	* Example: [2025-01-14 17:54:55,092 GMT−8] [INFO] Setup analytics
b69ab31	30	*/
b69ab31	31	export abstract class Logger {
b69ab31	32	abstract write(level: Level, timeStr: string, ...args: Parameters<typeof console.log>): void;
b69ab31	33
b69ab31	34	private writeLog(level: Level, ...args: Parameters<typeof console.info>): void {
b69ab31	35	const timeStr = `[${new Date().toLocaleString('sv', tzOptions)}]`;
b69ab31	36	this.write(level, timeStr, ...args);
b69ab31	37	}
b69ab31	38
b69ab31	39	/**
b69ab31	40	* @deprecated use .info instead
b69ab31	41	* TODO: we should just use info everywhere, I don't know the distinction between log and info,
b69ab31	42	* this was just for compatibility with console.log which isn't particularly important.
b69ab31	43	*/
b69ab31	44	log(...args: Parameters<typeof console.info>): void {
b69ab31	45	this.writeLog('log', ...args);
b69ab31	46	}
b69ab31	47
b69ab31	48	info(...args: Parameters<typeof console.info>): void {
b69ab31	49	this.writeLog('info', ...args);
b69ab31	50	}
b69ab31	51
b69ab31	52	warn(...args: Parameters<typeof console.info>): void {
b69ab31	53	this.writeLog('warn', ...args);
b69ab31	54	}
b69ab31	55
b69ab31	56	error(...args: Parameters<typeof console.info>): void {
b69ab31	57	this.writeLog('error', ...args);
b69ab31	58	}
b69ab31	59
b69ab31	60	/** Get all previously logged contents, usually for filing a bug report. */
b69ab31	61	getLogFileContents?(): Promise<string>;
b69ab31	62
b69ab31	63	levelToString(level: Level): string {
b69ab31	64	switch (level) {
b69ab31	65	case 'log':
b69ab31	66	return ' [LOG]';
b69ab31	67	case 'info':
b69ab31	68	return ' [INFO]';
b69ab31	69	case 'warn':
b69ab31	70	return ' [WARN]';
b69ab31	71	case 'error':
b69ab31	72	return '[ERROR]';
b69ab31	73	}
b69ab31	74	}
b69ab31	75	}
b69ab31	76
b69ab31	77	const GREY = '\x1b[38;5;8m';
b69ab31	78	const RED = '\x1b[38;5;9m';
b69ab31	79	const YELLOW = '\x1b[38;5;11m';
b69ab31	80	const CLEAR = '\x1b[0m';
b69ab31	81
b69ab31	82	/**
b69ab31	83	* Logger that prints to stdout via `console`, with ANSI escape coloring for easy reading.
b69ab31	84	* Typically used in dev mode.
b69ab31	85	*/
b69ab31	86	export class StdoutLogger extends Logger {
b69ab31	87	write(level: Level, timeStr: string, ...args: Parameters<typeof console.log>): void {
b69ab31	88	// eslint-disable-next-line no-console
b69ab31	89	console[level]('%s%s%s%s', GREY, timeStr, this.levelToString(level), CLEAR, ...args);
b69ab31	90	}
b69ab31	91
b69ab31	92	levelToString(level: Level): string {
b69ab31	93	switch (level) {
b69ab31	94	case 'log':
b69ab31	95	return GREY + ' [LOG]';
b69ab31	96	case 'info':
b69ab31	97	return GREY + ' [INFO]';
b69ab31	98	case 'warn':
b69ab31	99	return YELLOW + ' [WARN]';
b69ab31	100	case 'error':
b69ab31	101	return RED + '[ERROR]';
b69ab31	102	}
b69ab31	103	}
b69ab31	104	}