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Comment by simlevesque | Hacker News Reader

> Deno seems to be spending a lot of time and money into Node compat which so far (afaik) hasn't produced results.

These days there's almost nothing you can't do in Deno that you can do in Node. If you think there is, please reply here but I think that time has passed.

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The thing I ran into today was jsdom not seeming to work at all in Deno.

My use case was trying to run Playwright to scrape a site, copy the resultant HTML into jsdom, then run Mozilla's `readability` module on that to get a summary of the page. I found a replacement for Playwright (astral), and `readability` seems to be runtime agnostic as long as it has access to DOM APIs, but jsdom doesn't work with Deno yet.

I'd love to hear if there's an alternative to jsdom that I could use, because I unfortunately can't switch entirely over to NodeJS in this particular project, so either I find a replacement server-side DOM library, or I need to juggle two runtimes for different parts of the project. :/

JSDOM works on Deno. Here's a script:

  // from https://gist.github.com/kt3k/6123515ff5d1e167f82dfe4aa12ee5d9
  import { JSDOM } from "https://jspm.dev/jsdom";
  const doc = new JSDOM(`<!DOCTYPE html><p>Hello world</p>`);
  console.log(doc.window.document.querySelector("p").textContent);

Run it like this:

  deno run 'https://gist.githubusercontent.com/kt3k/6123515ff5d1e167f82dfe4aa12ee5d9/raw/f27520c629e56ab6e53e411c455ecc289300bb28/jsdom-in-deno.ts'

This returns "Hello world" on my machine, deno 2.3.1

I'd need more info about your problem but I'm not convinced that Deno's the problem and if there is one.

Jsdom should work in deno, can you open a github issue (https://github.com/denoland/deno/issues) with some details and a reproduction?

All of the simple cases I've tried seem to work fine, e.g:

  import { JSDOM } from "npm:jsdom";
  
  const dom = new JSDOM(
    `<!DOCTYPE html><p>Hello world <img src="https://example.com/logo.svg" /></p>`,
  );
  
  console.log(dom.window.document?.querySelector("p")?.textContent); // "Hello world"
  console.log(dom.window.document?.querySelector("img")?.getAttribute("src")); // "https://example.com/logo.svg"

Earlier today, it was producing an error that looked as if it couldn't render some elements. Unfortunately, I switched to a different branch where I tried to switch certain things over to Node, and now when I've switched back, there's a different error, now in the `readability` module, but still connected to its use of jsdom. It looks like it could be due to version mismatches — maybe readability requires a different version of JSDOM to the one installed by default — but now I'm trying to downgrade the currently installed version of JSDOM, and that doesn't seem to work — the version in deno.lock is stubbornly staying at the later version, despite having specified an older version in the `deno.jsonc` (and that older version appearing in the `workspace.dependencies` array at the bottom of the lock file).

I'll try again with a clearer head tomorrow, and maybe if I figure stuff out I can create a proper reproduction, but right now I don't know how to reproduce anything because it doesn't seem like my local environment is consistently reproducible, let alone trying to create something that would work on other machines. I'm surprised at how poor this behaviour is — I thought a big part of Deno@2 was to fix these sorts of dependency issues.

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