promise?

[AlJohri]

my code isn't really set to do stream based processing right now and I wanted a version that returned a promise so I wrote this:

async function parseSitemap(sitemapURL) {
  const urls = [];
  return await new Promise((resolve, reject) => {
    sitemaps.parseSitemaps(sitemapURL, url => urls.push(url), (err, sitemaps) => {
      if (err) reject(err);
      resolve(urls);
    })
  })
}

could you expose a promise version directly? happy to submit a PR

[AlJohri]

nevermind, this is pretty easy with utils.promisify.

const { promisify } = require('util');
const parseSitemaps = promisify(sitemaps.parseSitemaps);
async function parseSitemap(sitemapURL, keys) {
  const urls = [];
  const sitemaps = await parseSitemaps(sitemapURL, url => urls.push(url));
  return urls;
}

[evanderkoogh]

Hey @AlJohri, if you are adding an example for the other features (sitemap url and filter for subsequent sitemaps), could you add this as well? Might help more people in the future.

Thanks!

[AlJohri]

@evanderkoogh sweet, I'll give this a shot. one small note is that since the done callback is no longer the last argument I believe promisify will no longer work.

promisify() assumes that original is a function taking a callback as its final argument in all cases. If original is not a function, promisify() will throw an error. If original is a function but its last argument is not an error-first callback, it will still be passed an error-first callback as its last argument.

https://github.com/nodejs/node/blob/master/doc/api/util.md

since you just cut the release <24 hours ago, is there any easy solution you can think of here?

[evanderkoogh]

Hey, that is a very good catch. I was trying to avoid any sort of backward incompatibility..

But I can just do a check and shuffle some arguments around, which I have done. I have indeed yanked version 1.5.2 and released version 1.6.0 where the sitemap_test argument is optional.

The other thing I have added is a promise version of the parseSitemaps method. I have C&Ped the example I used to test it below. Would love some documentation update.

const test = async () => {
  await parser.parseSitemapsPromise(
    "https://calibreapp.com/sitemap.xml",
    console.log,
    sitemap => {
      console.log({ sitemap });
      return true;
    }
  );
};

[AlJohri]

Thanks for the speedy fixes @evanderkoogh. Let me implement this in my application and then I'll take a stab at updating the docs.

[AlJohri]

@evanderkoogh just looked at your implementation. I'm not sure its exactly right?

https://github.com/evanderkoogh/node-sitemap-stream-parser/commit/03fc2a706a582703e53e88e03de8647c5a813a75

I think you need to call reject in the event of an error. it would be something closer to

exports.parseSitemapsPromise = (urls, url_cb, sitemap_test) => 
    new Promise (resolve, reject) => {
            const done = (err, sitemaps) => {
                if (err) reject(err);
                resolve(sitemaps);
            }
            return exports.parseSitemaps(urls, url_cb, sitemap_test, done)
        }

or much more simply since we can rely on the convention of callback being the last argument and callback taking (err, result):

const { promisify } = require('util');
exports.parseSitemapsPromise = promisify(exports.parseSitemaps);

[pittersnider]

This definitely needs to get easier than it is.
My suggestion is to keep it promisified and objective:

const { urls, sitemaps } = await sitemap.parse('https://github.com/sitemap.xml')

[fotoflo]

Hello, only 5 years later... Is one of these solutions working?