A customizable logger library for Browser and NodeJS.

Features

• Simple and easy-to-use API
• Log level filtering
• Custom logger support
• Works with both Browser and NodeJS

Installation

npm install rt0-logger

Basic Usage

import { Log } from 'rt0-logger';

const log = new Log('test/module');

log.d('test'); // [debug] [test/module] test

Set Log Level

import { Log, type LogLevel } from 'rt0-logger';

const logLevel: LogLevel = 'info';

function createLogger(label: string) {
  return new Log(label, {
    getLogLevel: () => logLevel
  });
}

const log: Log = createLogger('test/module');

log.d('test'); // won't log anything
log.i('test'); // [info] [test/module] test

Advanced Usage

Custom Logger with Timestamps

import { Log, checkIfShouldLog, convertLevelTagToLogLevel, type LogLevel } from 'rt0-logger';

const logLevel: LogLevel = 'info';

function createLogger(label: string) {
  return new Log('test/module', {
    customLogger: ({ label, levelTag, callerArgs }) => {
      if (!checkIfShouldLog(logLevel, levelTag)) return;

      const dateTime = new Date().toISOString().replace('T', ' ').replace('Z', '');
      const level = convertLevelTagToLogLevel(levelTag);
      console[level](`[${dateTime}] [${levelTag}] [${label}]`, ...callerArgs);
    }
  });
}

const log: Log = createLogger('test/module');

log.d('test'); // won't log anything
log.i('test'); // [2021-08-01 12:00:00] [info] [test/module] test

Custom Logger with Colored Messages

import { colors } from 'rt0-logger/colors';
import { Log, checkIfShouldLog, convertLevelTagToLogLevel, type LogLevel } from 'rt0-logger';

const logLevel: LogLevel = 'info';

function createLogger(label: string) {
  return new Log(label, {
    customLogger: ({ label, levelTag, callerArgs }) => {
      if (!checkIfShouldLog(logLevel, levelTag)) return;

      const dateTime = new Date().toISOString().replace('T', ' ').replace('Z', '');
      const level = convertLevelTagToLogLevel(levelTag);
      console[level](colors[levelTag](`[${dateTime}] [${levelTag}] [${label}]`, ...callerArgs));
    }
  });
}

const log: Log = createLogger('test/module');

log.i('test'); // [2021-08-01 12:00:00] [debug] [test/module] test

License

MIT

README provided by GPT-4 🚀 (with some changes here and there)