@lautag/friday

Laut Javascript Error/Logging Framework

Installation

npm i @lautag/friday

Facade Driven

The preference is to have a facade driven logger which is extensible through compositions.

Available methods

## new LoggerFacade()
#.username(username) -> this
#.userEmail(userEmail) -> this
#.userId(userId) -> this
#.userIp(userIp) -> this
#.tag(key, value) -> this
#.level(level) -> this
#.extra(key, value) -> this
#.use(loggerName) -> this
#.getLogger(loggerName) -> exposed logger instance
#.addLogger(loggerName, logger)
#.removeLogger(loggerName)
#.removeAllLoggers()
#.hasLogger(loggerName) -> boolean

These are the RFC logger levels. They pass the message and any data set on the facade to the underlying loggers. Each logger should have a mapping of the RFC levels to the appropriate methods/levels exposed by that particular level. If you use one of these methods, any level set by .level(level) will/may be overwritten.

#.emergency(message)
#.alert(message)
#.critical(message)
#.error(message)
#.warning(message)
#.notice(message)
#.info(message)
#.debug(message)

These methods are provided for legacy/extended support on some transports. Each transport should define how to handle these methods. Generally speaking they should set a default level if applicable for the methods and accept the .level(level) as an override, however, this may be determined by the individual transport.

#.log(message)
#.message(message)

Transports available

1. Sentry
   1. Node
      • npm i @sentry/node required
   2. Browser
      • ǹpm i @sentry/browser required
   3. Vue
      • npm i @sentry/browser @sentry/integrations required
2. File
   1. Node only
3. Console
   1. Browser
   2. Node

Notes on Transports

Before using a specific transport, such as logging specific information to one logger and not another, it is recommended to check for the existence of the logger with #.hasLogger(loggerName) to minimize runtime errors.

Sentry

You need to build the Sentry instance separately and then pass it into the SentryLogger constructor. You can use the builders provided for each environment to make configuration easier SentryBrowser, SentryNode, and SentryVue. They take care of some sane defaults and expose a more eloquent api than Sentry itself does.

If you send an Error() as the message in #.message() then sentry will treat it as an exception ... any level you try to pass with be ignored and the level set to error. The #.message() is only intended to be used with strings in Sentry per their docs.

File

The file logger accepts a path to the folder where the log should be saved. Default is __dirname, which is probably not what you want. Your best bet is to give it an absolute path. Files are named according to the date in the form yyyy-mm-dd. Do not try to give a filename ... it won't work

The format is a similar to a syslog of the form:

** Timestamp: 2020-05-29T13:07:57.195Z, message: <message>[ ,data_key_1: data_key_1_value, ...]>

or you can pass a custom format function in the constructor:

{
  formatFn: (level, message, context) => any
}

Console

The console logger outputs <level> -- <message> by default. You can pass an optional function to the ConsoleLogger#constructor with a formatting you want. The options to the console logger are of the form:

{
  formatFn: (level, message, context) => any
} 

Vue Plugin

A Vue Plugin exposing the logger facade is included. Simply import the plugin and pass the configured instance of the friday logger as option.friday:

import FridayVue from '@lautag/friday'
const friday = <your configured logger>
Vue.use( FridayVue, { friday } )

Examples

Console

import {ConsoleLogger, LoggerFacade} from '@lautag/friday'

const consoleLogger = new ConsoleLogger()
const logger = new LoggerFacade()
logger.addLogger('console', consoleLogger)
logger.info("I'm a message")

File

import {FileLogger, LoggerFacade} from '@lautag/friday'

const fileLogger = new FileLogger({ filepath: '.' })
const logger = new LoggerFacade()
logger.addLogger('file', fileLogger)
logger.info( "I'm a message" )

Sentry

import {SentryBrowser, SentryLogger, LoggerFacade} from '@lautag/friday'

const sentryBuilder = new SentryBrowser()
const Sentry = sentryBuilder
    .dsn('https://mydsn.com')
    .env('production')
    .release('beta3')
    .make()
const sentryLogger = new SentryLogger(Sentry)

const logger = new LoggerFacade()
logger.addLogger('sentry', sentryLogger)
logger.info("I'm a message")

Multiple Loggers

import {SentryNode, SentryLogger, FileLogger, LoggerFacade} from '@lautag/friday'

const sentryBuilder = new SentryNode()
const Sentry = sentryBuilder
    .dsn('https://mydsn.com')
    .env('production')
    .release('beta3')
    .make()
const sentryLogger = new SentryLogger(Sentry)

const fileLogger = new FileLogger({ filepath: '.' })

const logger = new LoggerFacade()
logger.addLogger('file', fileLogger)
logger.addLogger('sentry', sentryLogger)

logger.info("I'm Logging to both instances")

logger.removeLogger('sentry')

logger.info("I'm just logging to a file now")