LogT

🖥️ A colorful logger for the browser

See it in action

Demo - https://sidhantpanda.github.io/logt/dist/

Features

• Small library size - Only ~1.45KB gzipped!
• Colorful labels to help distinguish logs by importance.
• Override default console methods to use custom logger instead, anywhere on the web page
• Log levels to hide less important log messages.
• Show hidden messages programmatically to print logs hidden due log level.
• Built with TypeScript for detailed type info and that sweet sweet autocomplete.

Installation

$ npm i logt -S

Usage

You can use this logger for your frontend projects. You can choose as an ES6 module or directly include the script in HTML.

As an ES6 module

Create a file in your project called logger.js or logger.ts

import LogT from "logt";

const LOG_TAG = "sample tag";
let logger;
if (process.env.NODE_ENV === "production") {
  logger = new LogT("error"); // or logger = new LogT("none");
} else {
  logger = new LogT("silly");
}

// See documentation for `readConsole()` for usage
// uncomment following line if you want to override default console methods
// logger.readConsole();

logger.error(LOG_TAG, new Error("example error"));

export default logger;

Include in HTML

<script src="https://cdn.jsdelivr.net/gh/sidhantpanda/logt/dist/logt.min.js"></script>
<script>
  var LOG_TAG = 'sample tag';
  var logger = createLogger('error');

  // See documentation for `readConsole()` for usage
  // uncomment following line if you want to override default console methods
  // logger.readConsole();

  logger.error(LOG_TAG, new Error('example error'));
</script>

Documentation

Logger initialization

import LogT from "logt";

let logger;
// Available log levels -  -1 | 0 | 1 | 2 | 3 | 4 | 5 | 'none' | 'error' | 'warn' | 'info' | 'verbose' | 'debug' | 'silly';

// noneLogger will print nothing
noneLogger = new LogT(-1); // or
noneLogger = new LogT("none");
// if included via HTML script
noneLogger = createLogger(-1); // or
noneLogger = createLogger("none");

// errorLogger will only error messages
errorLogger = new LogT(0); // or
errorLogger = new LogT("error");
// if included via HTML script
errorLogger = createLogger(0); // or
errorLogger = createLogger("error");

// sillyLogger will print all messages
sillyLogger = new LogT(5); // or
sillyLogger = new LogT("silly");
// if included via HTML script
sillyLogger = createLogger(5); // or
sillyLogger = createLogger("silly");

If any other value is supplied to the constructor, a default value of none is used.

APIs

error(logTag: string, message: any, ...rest: any[])

Parameters

• logTag - A log tag to identify the message and point to source of the message.
• message - The error log message
• ...rest - Any additional arguments to be passed onto console.error

warn(logTag: string, message: any, ...rest: any[])

Parameters

• logTag - A log tag to identify the message and point to source of the message.
• message - The warning log message
• ...rest - Any additional arguments to be passed onto console.warn

info(logTag: string, message: any, ...rest: any[])

Parameters

• logTag - A log tag to identify the message and point to source of the message.
• message - The info log message
• ...rest - Any additional arguments to be passed onto console.info

verbose(logTag: string, message: any, ...rest: any[])

Parameters

• logTag - A log tag to identify the message and point to source of the message.
• message - The verbose log message
• ...rest - Any additional arguments to be passed onto console.log

debug(logTag: string, message: any, ...rest: any[])

Parameters

• logTag - A log tag to identify the message and point to source of the message.
• message - The debug log message
• ...rest - Any additional arguments to be passed onto console.log

silly(logTag: string, message: any, ...rest: any[])

Parameters

• logTag - A log tag to identify the message and point to source of the message.
• message - The silly log message
• ...rest - Any additional arguments to be passed onto console.log

getLogLevel(): number

Returns the logger instance's log level in numeric form;

setLogLevel(logLevel: string | number)

Update a logger instance's logLevel dynamically later.

Parameters

• logLevel - New logLevel for the instance. Values: -1 | 0 | 1 | 2 | 3 | 4 | 5 | 'none' | 'error' | 'warn' | 'info' | 'verbose' | 'debug' | 'silly'

showHidden(logLevel: -1 | 0 | 1 | 2 | 3 | 4 | 5 | 'none' | 'error' | 'warn' | 'info' | 'verbose' | 'debug' | 'silly')

Show log messages hidden by the logger. Only logs equal or above logLevel will be shown.

Parameters

• logLevel - Log level for which logs are to be shown

Example

const logger = new LogT(0);
logger.warn("TAG", "warning message"); // Will not print anything to console
logger.info("TAG", "info message"); // Will not print anything to console
logger.debug("TAG", "debug message"); // Will not print anything to console
logger.silly("TAG", "silly message"); // Will not print anything to console

logger.showHidden(1); // Will print the warning message
logger.showHidden(2); // Will print the info message
logger.showHidden(5); // Will print the debug as well as silly message

readConsole()

Replace default console.error, console.warn, console.info, console.log implementation with logt logger.

Example

const logger = new LogT(0);
logger.readConsole();

console.error(new Error("test error")); // will be same as logger.error('console', new Error('test error'));
console.warn("warn message"); // will be same as logger.warn('console', 'warn message');
console.log("info message"); // will be same as logger.info('console', 'info message');
console.log("log message"); // will be same as logger.debug('console', 'log message');

Changelog

v1.5.0

• Deprecate image() method. Will be removed in next major release. Logging images is no longer supported by Chromme.

v1.4.0

• Added image() method

v1.2.0

• Added readConsole() method

Roadmap

Checkout the project page for details about future development.