Colorful 🌈 Semantic 📖 Logger 🔢 for Node.js
Overview
Fast and simple log service, which can highlight important words, types & tags. 👨🏻💻
Features
- [x] Colorful
🌈 - [x] Highlight reserved words
- [x] Highlight types
- [x] Highlight tags
- [x] Color by tags
- [x] Custom formatting
- [x] Configurable
- [x] Different log levels
- [x] Shortcodes
- [x] etc.
How to use
Install
- Install NodeJs (This will also install npm)
- Install @dmantsevich/colorful-semantic-logger as dependency for your project (
👍 ):
npm i @dmantsevich/colorful-semantic-logger --saveUsages
Simple
const { logger } = require('@dmantsevich/colorful-semantic-logger');
logger.log(`My log message`);
logger.debug(`My debug message`);
logger.verbose(`My verbose message`);
logger.info(`My info message`);
logger.warn(`My warn message`);
logger.error(`My error message`);
logger.fatal(`My fatal message`);
With name
const { Logger } = require('@dmantsevich/colorful-semantic-logger');
const logger = new Logger('Logger For My Package');
logger.log(`My log message`);
logger.debug(`My debug message`);
logger.verbose(`My verbose message`);
logger.info(`My info message`);
logger.warn(`My warn message`);
logger.error(`My error message`);
logger.fatal(`My fatal message`);
With options
const { Logger, LEVELS } = require('@dmantsevich/colorful-semantic-logger');
const logger = new Logger('MyPackage', { level: LEVELS.WARN }); // filter by only WARN+ criteria
logger.log(`My log message`);
logger.debug(`My debug message`);
logger.verbose(`My verbose message`);
logger.info(`My info message`);
logger.warn(`My warn message`);
logger.error(`My error message`);
logger.fatal(`My fatal message`);
Sub logger
const { Logger, LEVELS } = require('@dmantsevich/colorful-semantic-logger');
const packageLogger = new Logger('MyPackage', { level: LEVELS.DEBUG });
const logger = packageLogger.createNew('MyComponent', { level: LEVELS.FATAL }); // name will be: MyComponent.MyPackage
logger.log(`My log message`);
logger.debug(`My debug message`);
logger.verbose(`My verbose message`);
logger.info(`My info message`);
logger.warn(`My warn message`);
logger.error(`My error message`);
logger.fatal(`My fatal message`);
Tags
Tag is a text between <tagName>..that text will be processed..</tagName>. It helps to format & paint your message. Tags & their formats are configurable. See configuration.
Reserved words
Colorful Semantic Logger can highlights important words in your logs. See configuration.
API
Package
Default module exports next objects:
- ColorfulSemanticLogger(name, options): Main logger class. {name} - name/group for your custom logger. {options} - see configuration.
- Logger: the same as ColorfulSemanticLogger. Just shortname.
- logger: default instance of ColorfulSemanticLogger class with default options.
- LEVELS: Log levels. Levels: DEBUG, LOG, INFO, WARN, FATAL, ERROR, VERBOSE
- unpacked LEVELS object
Logger instance
For creating new logger, you need to create new instance:
const { Logger } = require('@dmantsevich/colorful-semantic-logger');
const logger = new Logger('My New Logger', {});
logger.log('I want to say: <underline>Hello World!</underline>');
Methods
-
logger.debug(msg, ...): Print
debugmessage -
logger.verbose(msg, ...): Print
verbosemessage -
logger.info(msg, ...): Print
infomessage -
logger.log(msg, ...): Print
logmessage. The same asinfo, but white. -
logger.warn(msg, ...): Print
warnmessage. -
logger.error(msg, ...): Print
errormessage. -
logger.throwError(msg, ...): Print
errormessage and then throw new Error. -
logger.fatal(msg, ...): Print
fatalmessage. -
logger.throwFatal(msg, ...): Print
fatalmessage and then throw new Error. -
logger.print(infoMsg, verboseMsg): Easy way to print different messages for
INFO&VERBOSElevels. - logger.createNew(name[, options]): create new sublogger. Sublogger uses namespace(split by dot) and same configuration.
- logger.removeTags(msg, ...): remove tags(only tags, not content) from message.
- Logger.LEVELS (static property in the class): Contains levels: LOG, INFO, DEBUG, VERBOSE, FATAL, ERROR, WARN
Configuration
Options for ColorfulSemanticLogger(name, options) or Logger(name, options) class.
| Param | Type | Default Value | Description |
|---|---|---|---|
level |
{object} | LEVELS.INFO | Default log level. Can be overrided with commandline: --log-level=error |
colorful |
{bool} | true | Output should be colored or not |
semanticData |
{object} | See: lib/options.js | Configuration for semantic parser |
semanticData.tags |
{object} | See: lib/options.js | Predefined tags. Key is "tagName". Value is function or string hex color. Function retrieve 2 argumentas: innerTagText, logger instance |
semanticData.reservedWords |
{array} | See: lib/options.js | Array with objects. words: array of reserved words. color: function or string hex color. Function retrieve 2 argumentas: reservedWord, logger instance |
shortCodes |
{object} | See: lib/options.js | Object with shortcodes. Key is shortcode. Value is function. Function retrieve: logger instance |
headerFormat |
{string/function} | <time.now/> <level/> <loggerName/>: | Header format. Can be string or function. String supports options.shortCodes. Function retrive logger instance |
Semantic Data - Tags
Predefined tags: number, key, value, ! (important!), path.
Also possible to use chalk API as tags. Example:
const { Logger } = require('@dmantsevich/colorful-semantic-logger');
const logger = new Logger('My Test Logger');
logger.log('It will be <red>Red</red>!');
logger.log('It will be <bgCyan>Background Cyan</bgCyan>!');
logger.log('It will be <bold>Bold</bold>!');
logger.log('It will be <#FF8C00>Orange</#FF8C00>!');
logger.log('It will be <bg#FF8C00>Background Orange</bg#FF8C00>!');
logger.log('It will be <green.underline.italic>Green + Underline + Italic</green.underline.italic>!');
How to use:
const { Logger } = require('@dmantsevich/colorful-semantic-logger');
const logger = new Logger('My Test Logger');
logger.log(`PI is <number>3.14</number>`); // 3.14 will be highlighted
logger.log(`Key: <key>myKey</key>. Values: <value>null</value>, <value>3.14</value>, <value>true</value>, <value>hello</value>.`); // null, 3.14, true, hello will be highlighted
logger.log(`Path to module: <path>${__dirname}</path>.`); // __dirname value will be highlighted and parsed as path(relative for cwd).
How to define new
{
makeRed: '#ff00ff', // tag is makeRed. color will be "#ff00ff" <makeRed>Hello World</makeRed>
status: (v, logger) => 'Status:' + logger._paint(v, '#40e0d0') // tag is "status". Use: <status>200</status> -> Status: 200 (where 200 will be green).
}Semantic Data - Reserved Words
Reserved words helps to highlight important words in your logs.
Predefined reserved words:
- group "ok": 'success', 'successful', 'ok', 'done', 'fine', 'connected', 'resolved', 'cool' : underlined + green
- group "not ok": 'fail', 'error', 'errors', 'fatal', 'reject', 'rejected', 'issue', 'disconnect', 'disconnected', 'issue', 'bug', 'problem', 'problems', 'exception', 'exceptions', 'throw' : bold + red
How to use
logger.log(`Connection is ok!`); // ok will be highlighted
logger.log(`Request was successful`); // successful will be highlighted
logger.log(`Promise was resolved & connected to DB`); // resolved & connected will be highlighted
logger.log(`Connection is fail!`); // fail will be highlighted
logger.log(`Some problems with your code.`); // problems will be highlighted 
How to define new
[{
words: ['start', 'begin'], // start action
color: (value, logger) => logger._paint(value, 'cyan')
}, {
words: ['end', 'complete'], // end action
color: (value, logger) => logger._paint(value, 'magenta')
}]ShortCodes
ShortCodes uses for head formating (example: <time.now/> <level/>(<random/>): ).
Default ShortCodes: <time.now/>, <date.now/>, <loggerName/>, <level/>
Example:
{
'random': (logger) => Math.random(),
'random.color': 'gray'
}Links
2021