simple node script to download files from a csv

download-from-csv.js

// to run
// ./download-from-csv.js csvfile.csv
// will download anything in the csv file under the col:
const colName = 'URL' 
const fileDir = 'output_files' // to this subdirectory of the current dir

const csv = require('csvtojson')
const fs = require('fs')
const path = require('path')
const https = require('https')

const filename = process.argv[2]
const filepath = `${__dirname}/${filename}`
const extension = path.extname(filepath)

;(async () => {
  main()
})();

async function main(){

  try {
    if (fs.existsSync(filepath) && extension === '.csv') {
      const results = await csv().fromFile(filepath);
      results.map(r => {
        console.log(r[colName]) // URL is the col in the csv
        const url = new URL(r[colName]);
        let filename = url.pathname.split("/")
        filename = filename[filename.length - 1]
        if (!fs.existsSync(`${__dirname}/${fileDir}/`)){
          fs.mkdirSync(`${__dirname}/${fileDir}/`);
        }
        filename = `${__dirname}/${fileDir}/${filename}`
        const file = fs.createWriteStream(filename);
        const request = https.get(url, function(response) {
          response.pipe(file);
        });
      })
    } else {
      console.error(`please give a valid filename for a csv in the current directory`)
      process.exit(1)
    }
  } catch(err) {
    console.error(`unexpected error `, err)
  }
}