is `url.format` broken or am I?

[beck]

Using Node@9.9 on OSX.

Problem

> const url = require('url')
> url.format({hostname: 'dougbeck.me', pathname: 'womp.html'})
'dougbeck.mewomp.html'
> 😭

Am I crazy for thinking this is broken behavior?

Granted, this seems to be terrible in every other language:

Python

>>> urllib.parse.urlunparse(('', 'dougbeck.me', 'womp.html', '', '', ''))
'//dougbeck.me/womp.html'

Requiring a 6-item tuple is gross.

Ruby

> URI::HTTP.build(host: 'dougbeck.me', path: 'womp.html').to_s
ERROR expected absolute path

Java

> new URL("dougbeck.me").toString()
ERROR: no protocol

Node's behavior is worse than all of ☝️because it does not throw an error and returns a result that defies all intuition. 😖

[devsnek]

url.format is legacy, you should use the whatwg URL api

[addaleax]

👍 to what @devsnek said

But also, yes, this is terrible and we should probably fix it. Would you be willing to open an issue @ https://github.com/nodejs/node/, for visibility?

[beck]

you should use the whatwg URL api

Lets give that a shot...

> const url = require('whatwg-url')
> url.serializeURL({host: 'dougbeck.me', path: 'womp.html'})
'undefined://undefined:undefined@dougbeck.me:undefined/w/o/m/p/./h/t/m/l?undefined#undefined'

¡Dios mííío!

whatwg-url is great when starting with a url string. Digging through the source, I have no clue how to create a URL object or url string from parts. For my use case, there is no starting url string since some parts are sourced from config.

I'm being a bit facetious, it is super easy to build a url with string munging or a template string but I'd very much like to use a lib and be confident I'll never see a double slash.

I'm on the hunt for a lib that accepts:

• domain
• path
• query dictionary

and returns:

• a fetchable url string
• where query params are properly concatenated and url encoded
• and free of //

Maybe I'm asking for too much.

[ORESoftware]

Yeah I guess it should be:

> const url = require('url')
> url.format({hostname: 'dougbeck.me', pathname: '/womp.html'});  // with a slash
'dougbeck.me/womp.html'

but I agree that the slash should not be necessary, that would nice. this does seem problematic... these url parsing things can be a pain in the arse in any language. I also agree that it should throw if there is an obvious formatting problem (in the next Node.js major version).

[addaleax]

@beck I think the intention was not to point to that module, but rather to https://nodejs.org/api/url.html#url_the_whatwg_url_api

const url = new URL('https://./');  // Dummy HTTPS URL
url.hostname = 'foo';
url.pathname = 'bar';
url.search = new URLSearchParams({a: 'b'});
console.log(url.href);  // => 'https://foo/bar?a=b'
// console.log(url);

[jasnell]

The point being, the WHATWG URL API is now implemented in core and is generally available and should be what is used.

[beck]

to open an issue for visibility

nodejs/node#19523

@addaleax the dummy url is ugly but good. Minor edit would be to document via code:

const dummyURL = 'https://./';
const url = new URL(dummyURL);

I like this approach. Thank you.