JS Logger

logger.js

const DEBUG = true
// const DEBUG = process.env.NODE_ENV !== 'production'
const LOG_DATE = true
const LOG_LOCALE = "en-US"
const LOG_DATE_OPTS = { year: 'numeric', month: 'long', day: 'numeric', hour: '2-digit', minute: '2-digit', second: '2-digit' }

const log = function (level, ...args) {
  if (DEBUG) {
    let prefix = ''
    if (typeof level === 'string' && [ 'log', 'warn', 'error' ].includes(level)) {
      prefix = level.toUpperCase()
      if (LOG_DATE) {
        prefix += ' | ' + (new Date()).toLocaleString(LOG_LOCALE, LOG_DATE_OPTS)
      }
      prefix = '[ ' + prefix + ' ] '
    } else {
      args.unshift(level)
      level = 'log'
    }
    if (prefix !== '')
      args.unshift(prefix)
    
    console[level].apply(console, args)
  }
}

simple.js

const log = (level, ...args) => {
  if (typeof level !== 'string' || !([ 'log', 'warn', 'error' ].includes(level)))
    level = args.unshift(level) && 'log'
  console[level].bind(console)(...args)
}