sematextBrowserLogger.js

function sematextLogger (url, token) {
  var sematextUrl = url || `https://logsene-receiver.sematext.com/${token}/_bulk/`
  var logBuffer = ''
  let consoleLog = console.log
  let lineCount = 0
  const sessionId = /SESS\w*ID=([^;]+)/i.test(document.cookie) ? RegExp.$1 : false
  let consoleFunctions = {
    debug: console.debug,
    error: console.error,
    warn: console.warn,
    log: console.log,
    info: console.info
  }
  function logLine (logLine) {
    var line1 = JSON.stringify({ 'index': { '_index': sematextLogToken, '_type': 'browser_logs' } })
    logBuffer = logBuffer + (line1 + '\n' + logLine + '\n')
  }
  function sematextShipLogs () {
    if (lineCount === 0) {
      return
    }
    const http = new XMLHttpRequest()
    http.open('POST', sematextUrl, true)
    http.setRequestHeader('Content-type', 'application/json')
    http.send(logBuffer)
    http.onresponse = consoleLog
    logBuffer = ''
    lineCount = 0
  }
  function sematextLog (severity) {
    let args = new Array(arguments).slice(1)
    consoleFunctions[severity](...args)
    if (arguments.length > 1) {
      if (typeof arguments[1] === 'string') {
        logLine(JSON.stringify({
          message: arguments[1],
          '@timestamp': new Date(),
          sessionId: String(sessionId),
          severity: severity,
          location: window.location
        }))
      } else {
        logLine(JSON.stringify({
          msg: arguments,
          '@timestamp': new Date(),
          sessionId: String(sessionId),
          severity: severity,
          location: window.location
        }))
      }
      lineCount++
      if (lineCount > 100) {
        sematextShipLogs()
      }
    }
  }

  console.log = function () { sematextLog('info', ...arguments) }
  console.error = function () { sematextLog('error', ...arguments) }
  console.warn = function () { sematextLog('warn', ...arguments) }
  console.debug = function () { sematextLog('debug', ...arguments) }

  setInterval(sematextShipLogs, 5000)
}