logger

logger for nodejs

Install

$ npm i @zhangfuxing/logger

Node.js 12+ required (Because of use Class private fields)

options

When isTTY is false, logger will not write to terminal.

constructor

• dir optional, Log folder path, if it is given, it will log to file
• rotate optional, Whether cut logs by day
  • default: false
• disableConsole optional, disable write to terminal
  • default: false

info

• args The message to write

info(...args: any[]): void;

warn

• args The message to write

warn(...args: any[]): void;

error

• args The message to write

error(...args: any[]): void;

disableConsole

disable write to terminal

disableConsole(): void;

enableConsole

enable write to terminal

enableConsole(): void;

disableFile

disable write to file

disableFile(): void;

enableFile

enable write to file

enableFile(): void;

disable

disable write to file and terminal, don't care if it is currently writing to a file or terminal, but hope to restore the currently configuration later

disable(): void;

enable

restore previous log configuration: file, terminal or both

enable(): void;

Useage

console logger

const Logger = require('@zhangfuxing/logger');

const logger = new Logger();

logger.info('consoleLogger info', { name: 'zfx' });
logger.warn('consoleLogger warn', 1, 'any');
logger.error('consoleLogger error', new Error('test'));

file and console logger

const Logger = require('@zhangfuxing/logger');

const logger = new Logger({
  dir: './log'
});

logger.info('fileLogger info', 'any', { name: 'zfx' });
logger.warn('fileLogger warn', 'any', 'any');
logger.error('fileLogger error', 'any', new Error('test'), 'any');

file logger only

const Logger = require('@zhangfuxing/logger');

const logger = new Logger({
  dir: './log',
  disableConsole: true
});

logger.info('fileLogger info', 'any', { name: 'zfx' });
logger.warn('fileLogger warn', 'any', 'any');
logger.error('fileLogger error', 'any', new Error('test'), 'any');

file logger cut by day

const Logger = require('@zhangfuxing/logger');

const logger = new Logger({
  dir: './log',
  rotate: true 
});

logger.info('fileLogger info', 'any', { name: 'zfx' });
logger.warn('fileLogger warn', 'any', 'any');
logger.error('fileLogger error', 'any', new Error('test'), 'any');

disableConsole and enableConsole

const Logger = require('@zhangfuxing/logger');

const logger = new Logger();

logger.info('console enabled, you can see me');
logger.info('console will be disabled, should not see "console disabled" below ===>');
logger.disableConsole();
logger.info('console disabled');
logger.enableConsole();
logger.info('console enabled, you can see me');

or disableConsole is true when the logger is instantiated

const Logger = require('@zhangfuxing/logger');

const logger = new Logger({
  disableConsole: true
});

logger.enableConsole();
logger.info('console enabled, you can see me');
logger.info('console will be disabled, should not see any below ===>');
logger.disableConsole();
logger.info('console disabled');

disableFile and enableFile

const Logger = require('@zhangfuxing/logger');

const logger = new Logger({
  dir: './log',
  disableConsole: true
});

logger.info('file enable');
logger.info('file will be disabled, should not see "file disbaled" below ===>');
logger.disableFile();
logger.info('file disbaled');
logger.enableFile();
logger.info('file enabled, you can see me');

disable and enable

1. fileLogger => disable => enable => fileLogger
2. consoleLogger => disable => enable => consoleLogger
3. fileLogger, consoleLogger => disable => enable => fileLogger, consoleLogger

const Logger = require('@zhangfuxing/logger');

const consoleLogger = new Logger();
const fileLogger = new Logger({
  dir: './log',
  disableConsole: true
});
const bothLogger = new Logger({
  dir: './log'
});

// fileLogger => disable => enable => fileLogger 
fileLogger.info('print by fileLogger, should not see "fileLogger disabled"');
fileLogger.disable();
fileLogger.info('fileLogger disabled');
fileLogger.enable();
fileLogger.info('fileLogger enabled, should see me just in file');

// consoleLogger => disable => enable => consoleLogger 
consoleLogger.info('print by consoleLogger, should not see "consoleLogger disabled"');
consoleLogger.disable();
consoleLogger.info('consoleLogger disabled');
consoleLogger.enable();
consoleLogger.info('consoleLogger enabled, should see me just in terminal');

// fileLogger, consoleLogger => disable => enable => fileLogger, consoleLogger 
bothLogger.info('print by bothLogger, should not see "bothLogger disabled"');
bothLogger.disable();
bothLogger.info('bothLogger disabled');
bothLogger.enable();
bothLogger.info('bothLogger enabled, should see me both in file and terminal');

Test

$ npm test

More test file in the test folder.

Screenshots

consoleLogger

fileLogger

cut logs by day

More screenshots in the screenshots folder.