@robinlemon/logger NPM

Installation

This is a Node.js module available through the npm registry.

Before installing, download and install Node.js. Node.js 6.0 or higher is required.

Installation is done using the npm install command:

$ npm install @robinlemon/logger

Usage

Quickstart

import Logger, { Levels } from '@robinlemon/logger';

const logger = new Logger({
    Name: 'Main',

    /* Unnecessary */
    Suppressed: false,

    /* Unnecessary */
    DefaultLevel: LogLevel.INFO,

    /* Unnecessary */
    InspectOptions: {
        showHidden: false,
        showProxy: false,
        depth: 2,
        colors: true,
        compact: false,
    },
});

/**
 * Development Logging
 */
logger.Log((process.env.NODE_ENV = 'development')) // -> INFO: development
logger.Log('foo'); // -> INFO: foo
logger.Log(LogLevel.SILLY, 'foo'); // -> SILLY: foo

/**
 * Production Logging
 */
logger.Log((process.env.NODE_ENV = 'production')) // -> INFO: production
logger.Log('foo'); // -> INFO: foo
logger.Log(LogLevel.SILLY, 'foo'); // -> Not printed

/**
 * Suppressing
 */
logger.Log('foo') // -> INFO: foo
logger.Hide();
logger.Log('foo'); // -> Not printed
logger.Show();
logger.Log('foo'); // -> INFO: foo

/**
 * Colours
 */
logger.Log('%red%foo%'); // -> INFO: foo (in red)

Levels

Available Logging Levels:

export const LogLevel = {
    'ERROR': Symbol('error'),
    'WARN': Symbol('warn'),
    'INFO': Symbol('info'),
    'VERBOSE': Symbol('verbose'),
    'DEBUG': Symbol('debug'),
    'SILLY': Symbol('silly'), 
};

Constructor Options

All constructor options are optional.

Option	Type	Default	Description
`Name`	`string` or `undefined`	`undefined`	A label that is printed when `Log` is called. If set to `undefined` no label will be printed.
`MaxLevel`	`LogLevel`	`'INFO'` or `'SILLY'`	The maximum level that should be printed, setting this to `INFO` and logging under `SILLY` will not print the silly leveled message. If `NODE_ENV` is not set to `production` this will automatically be set to `SILLY`, otherwise it will be `INFO` - unless explicitly overriden by constructor option.
`DefaultLevel`	`LogLevel`	`'INFO'`	The `LogLevel` to use when one is not provided to `Log`.
`Suppressed`	`boolean`	`false`	Whether the logger should respond to `Log` calls.
`InspectOptions`	Identical to util.inspect	See below.	The options to pass to NodeJS's `util.inspect` for `objects`.

export const DefaultOptions: Required<ILoggerOptions> = {
    Name: '',
    DefaultLevel: LogLevel.INFO,
    MaxLevel: LogLevel.INFO,
    Suppressed: false,
    InspectOptions: {
        showHidden: false,
        showProxy: false,
        depth: 2,
        colors: true,
        compact: false,
    },
};

Colouring

Any string of the following format will be interpolated to remove the percentage symbols.

This module supports all colour namespaces from Chalk.

`%${ColorName}%${Message}%`

Instance Properties

Note that all of the properties on this class are readonly except Name.

Name

Type: string

Description: The Logger instance's name.

new Logger({ Name: 'foo' }).Name // -> foo

DefaultLevel

Type: string

Description: The default level that is used to log when one is not provided as a lowercase string.

new Logger({ DefaultLevel: LogLevel.SILLY }).DefaultLevel // -> silly

MaxLevel

Type: string

Description: The maximum level the logger will print as a lowercase string.

new Logger({ MaxLevel: LogLevel.WARN }).MaxLevel // -> warn

isSuppressed

Type: boolean

Description: A boolean determining if the Logger instance is suppressed.

new Logger({ Suppressed: true }).isSuppressed // -> true

Instance Methods

All instance methods return the class reference (this).

Hide

Suppresses log output.

new Logger().Hide();

Show

Removes the log suppression.

new Logger().Show();

Space

Prints an empty line.

new Logger().Space();

Log

Writes to std::out given a logging level and list of items to print.

/**
 * @param Level The logging level to use.
 * @param Items Infinite arguments here of things to log.
 * @returns The current Logger instance.
 */
Log(Level?: LogLevel, ...Items: unknown[]): this;

new Logger().Log('foo');
new Logger().Log(LogLevel.SILLY, 'foo');
new Logger().Log('foo', 'bar', 'baz');
new Logger().Log(LogLevel.SILLY, 'foo', 'bar', 'baz');