[feat] Switch to `undici` (PR welcome) about superagent

[titanism]

This would be a major semver bump and large rewrite.

[jimmywarting]

👍 for this!

Looking at the dependency graph: https://npmgraph.js.org/[email protected]
i see things like formidable and form-data

it would be nice to replace them with undici or NodeJS FormData stuff.
parsing formdata could be as simple as using Response/Request.formData() all doe you get a FormData back along with File instances that are real web stuff

[titanism]

yeah it would be amazing to have all functionality of superagent (e.g. retrys) on top of undici

[jimmywarting]

Could you maybe create a new brach?

i would expect there to be kind of many breaking changes...

• require at least NodeJS v16.8 (required by undici)
• build things using fetch, FormData, Blob, File, Response, Request
• dropping total support for XHR and only using fetch
  • that could mean that it would also work in service workers
  • Node runtime could use pretty much the same codebase
• maybe this could be switched to ESM syntax?
• if XHR and http(s) gets replaced with fetch then we also loose progress monitoring
• things like this won't work anymore:

.on('request', function () {
  this.xhr.responseType = 'arraybuffer';
})

it's going to be a Request instead or a Request-like object so that it can be modified before initiating a fetch call so cache and other can be modified.

I could expect blob/files could be used on the backend as well along with FormData
NodeJS just recently introduced const blob = await fs.openAsBlob(path, { type })
but there is no sync method, and it only works in NodeJS v20+

to solve this problem then fetch-blob could be used instead. but it's ESM-only
so loading it would be hard unless this pkg dose not also becomes ESM enabled.

another approch would be to import fetch-blob async using import()
then attach() would kind of have to queue up all those path -> Blob conversions.

or we would have to read the files content sync and create a Blob in memory...

[titanism]

@jimmywarting this all sounds amazing. we just gave you collab access to the entire @ladjs org.