Deno•8mo ago

Possible to use CsvParseStream in Node.js

Hi, is it possible to use nodejs file streams with deno's stdlib?

import fs from "node:fs";
import { CsvParseStream } from "@std/csv";

fs.createReadStream("./data.csv")
  .pipe(new CsvParseStream()); // incompatible types

import fs from "node:fs";
import { CsvParseStream } from "@std/csv";

fs.createReadStream("./data.csv")
  .pipe(new CsvParseStream()); // incompatible types

nefOP•5/8/25, 6:47 AM

as far as I can tell there's nothing in or that opens a file

nefOP•5/8/25, 6:50 AM

I'm sure loading to a string is possible, but the file is fairly big

marvinh.•5/8/25, 9:59 AM

There is no function to open a file in any of the packages, because that's already included in Deno itself, see https://docs.deno.com/examples/streaming_files/

nefOP•5/8/25, 10:16 AM

yeah sorry I'm trying to use the libraries from node.js with jsr's node compatibility

nefOP•5/8/25, 10:18 AM

I'm still interested if it's possible but for now I'm using npm's

marvinh.•5/8/25, 10:37 AM

Right, in that case it's likely that you're running into the issue that Node by default uses NodeStreams (older API) and is written for WebStreams. In Node you can convert between the two, see https://nodejs.org/api/webstreams.html#nodejs-streams-interoperability

nefOP•5/8/25, 10:39 AM

oooh that looks like it, thank you!

nefOP•5/20/25, 7:08 AM

I'm looking into this again and got it working, but typescript is complaining about the types:

marvinh.•5/20/25, 7:16 AM

I'm not sure at the top off my head how to resolve that error, but you could also go with the Deno-native version when you're using Deno in the first place: