Temporarily write file to /tmp

Serverless Framework
1

Hello,
I have a aws lambda function which reads some log files from S3 and does some transformation on these and then creates a new file which I want to gzip and save to an FTP location

Here is the code I have:

'use strict'
const fs          = require('fs')
const path        = require('path')
const aws         = require('aws-sdk')
const s3          = new aws.S3()
const zlib        = require('zlib')
const s3stream    = require('s3-streams')
const R           = require('ramda')
const readline    = require('readline')
const namedRegExp = require('named-regexp-groups')
const moment      = require('moment')
const s3Upload    = require('./s3Upload')

const elbExp = R.always(/([0-9-]+T[0-9:]+\.\S+)\s+\S+\s+(\S+):\d+\s+(\S+):\d+\s+\S+\s+\S+\s+(\S+)\s+(\S+)\s+\S+\s+\S+\s+(\S+)\s+\"(\S+)\s+\w+:\/\/([\w\-\.]*):\S+(\/([^?]+)\S+\s+)([^\"]+)+\"\s+\"([^\"]+)\"\s+\S+\s+\S+/)
const elbRegExp = new namedRegExp(elbExp())

const splitElbEntry = (elbLogEntry) => elbRegExp.exec(elbLogEntry)
const elbToNginx = R.map((val) => val, splitElbEntry)

const dateToNginx = (date) => moment(date).format('DD/MMM/YYYY:HH:mm:ss ZZ')
const nginxTimestamp = (timestamp) => dateToNginx(timestamp)
const elbToNginxLog = (nginxMap) => `${nginxMap[1]}, ${nginxMap[2]} -- [${nginxTimestamp(nginxMap[0])}] "${nginxMap[6]} ${nginxMap[8]} ${nginxMap[10]}" "-" ${nginxMap[4]} ${nginxMap[5]} "${nginxMap[7]}" "${nginxMap[11]}" "-"`

const appendLog = (log) => fs.appendFile('/tmp/abc.log', log, (err) => {
  console.log(log)
  if (err) throw err
  console.log(`The log was updated! ${log}`)
})

module.exports = function s3Listing(...args) {
  const parsedList = args[0].map( record => {
    const params = {
      Bucket: process.env.BUCKET,
      Key: record.Key
    };
    const isGzip = path.extname(params.Key) === ".gz"
    let readStream = s3.getObject(params).createReadStream()
    readStream = isGzip ? readStream.pipe(zlib.createGunzip()) : readStream

    let lineReader = readline.createInterface({
      input: readStream
    });

    lineReader.on('line', (elbLogEntry) => {
      // console.log(elbLogEntry)
      // if(R.test(/^__utm.gif/, elbLogEntry)){
      if(elbLogEntry.includes("__utm.gif")){
        const elb = elbToNginx(elbLogEntry)
        const nginxMap = elb.groups

        appendLog(elbToNginxLog(nginxMap))
      }
    })
    lineReader.on('close', () => {
      console.log("end and close stream")
      s3Upload('/tmp/abc.log')
    });
  })
}

I get a Error: ENOENT: no such file or directory, open '/tmp/abc.log' error

What am I missing?

Any advice is much appreciated

2

Any news on this?
I’m facing the same issue…