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I am parsing CSV in node.js using csv-parser lib. But I need that parsed data would be avaliable in the whole project, not only in 'fs' section. I know that there is fs.readFileSync option but it does not useful since CSV is binary file (at least in node.js interpretation). What should I do?

const csv = require("csv-parser");
const fs = require("fs");


const cities = [];


let content = fs.createReadStream('data.csv')
  .pipe(csv())
  .on('data', (row) => {
    cities.push(row);
  });

  

var city_data = {
    createArrayId: function(){
        console.log(cities);
        return cities;
    }
}

module.exports = city_data;

As you can see, I need to export "cities" array. Right now it returns empty value (initialized value).

Ilia Soloveychik
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  • There are much nicer csv libraries out there. Check out `papaparse` which parses strings/buffers instead of files and is therefore always synchronous (for very large strings there is an option to use asynchronous process via web workers but that is only for the browser not node). You can use `fs.readFileSync` to read the file synchronously before passing it to `papaparse` – slebetman Feb 19 '21 at 19:49

1 Answers1

2

csv-parser seems to always be asynchronous, so you're out of luck there.

If data.csv doesn't change often, I'd recommend parsing it into JSON once and then require the JSON directly.

Otherwise, you can either implement synchronous CSV parsing yourself, or alternately refactor your code to wait until the asynchronous parsing is complete before carrying on with that data.

AKX
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