Add a utility to convert file URL or path to one of them?

[fisker]

What is the problem this feature will solve?

It's a nice way to accept both URL and path string in API, but we need covert it to either string or URL, it would be nice to have a built-in method to do this.

What is the feature you are proposing to solve the problem?

For converting to string:

Maybe add path.from(URL | string)? @sindresorhus proposed here.

For converting to URL:

url.from(URL | string)

I'm not sure, since URL is a standard, I guess adding method URL object won't be acceptable, maybe to node:url module?

What alternatives have you considered?

No response

[aduh95]

We have a toPathIfFileURL internal API already, maybe we could expose it in the node:url module

node/lib/internal/url.js

Lines 1558 to 1562 in 38b7961

	function toPathIfFileURL(fileURLOrPath) {
	if (!isURLInstance(fileURLOrPath))
	return fileURLOrPath;
	return fileURLToPath(fileURLOrPath);
	}

For converting to URL:

url.from(URL | string)

I don't think there is any reliable way to check if a string is a path or a file URL... I'm afraid the best option here is to assume that a string is a path and call pathToFileURL(string) (which is what is doing Node.js internally as well) – or if you prefer to assume strings are URLs in your application, call new URL(string).

[sindresorhus]

We have a toPathIfFileURL internal API already, maybe we could expose it in the node:url module

Wouldn't it be more natural to have it in node:path, since we want to convert it to a path? My proposal for path.from() was inspired by Array.from and Buffer.from type methods.

[sindresorhus]

I don't think there is any reliable way to check if a string is a path or a file URL...

To be clear, the string in that example is meant to be a file path, not a string file URL.

Example usage:

import path from 'node:path';

// Passthrough
path.from('/Users/sindresorhus/dev');
//=> '/Users/sindresorhus/dev'

path.from(new URL('file:///Users/sindresorhus/dev'));
//=> '/Users/sindresorhus/dev'

[benjamingr]

Is this what you had in mind in terms of semantics? benjamingr@0704851#diff-6610c8d452ba38a0db8c591e06af555bc7755ace17065a066c853ffcc5271559R7-R20

[fisker]

Yes, that's what I want.

[benjamingr]

@aduh95 wdyt about an implementation that does that? ( #41521 (comment) )

[aduh95]

@aduh95 wdyt about an implementation that does that? ( #41521 (comment) )

I don't think we'll get consensus landing in core something that treats differently a string depending on if it starts with file: or not – what if the user meant ./file:/ (i.e. they really have a local directory named file:)?

The workarounds that come to mind are:

• only support absolute paths – or require relative paths to start with a . (like in require calls).
• always treat a string as a path.
• publish this as an npm module instead (I think npm module would get away with not supporting having directory named file:).

Any combination of the above would address my concern, but I'm open to other ideas if someone thinks of something else.

[benjamingr]

@aduh95 I think it's safe to say "if this can be an npm module, sindre has already probably published one" :D Making small useful modules kind of their thing.

Edit: lol found it https://www.npmjs.com/package/file-url
Edit2: actually that's the other side of conversion

[benjamingr]

Basically: I think the main issue with this being on npm is that file urls and paths are both very common in modern Node.js and not having a utility to convert them in core is weird.

I'm sure we can bikeshed the name and semantics as long as the core use case (convert file url to path) is addressed.

Would it be better if the name was explicit path.fromFileUrl that only takes either a file:// url string or an actual URL with the file protocol and throws an error on non-file urls?

[sindresorhus]

I have no need for supporting file:// strings.

What I would like is:

export const from = urlOrPath => urlOrPath instanceof URL ? fileURLToPath(urlOrPath) : urlOrPath;

import path from 'path';

path.from('/Users/sindresorhus');
//=> '/Users/sindresorhus'

path.from(new URL('file:///Users/sindresorhus'));
//=> '/Users/sindresorhus'

[sindresorhus]

Would it be better if the name was explicit path.fromFileUrl that only takes either a file:// url string or an actual URL with the file protocol and throws an error on non-file urls?

No, this does not solve the request.

[benjamingr]

So you would expect:

path.from('file:///Users/sindresorhus');
//=> file:///Users/sindresorhus

?

[targos]

Edit: was already mentioned above

I have no need for supporting file:// strings.

What I would like is:

export const from = urlOrPath => urlOrPath instanceof URL ? fileURLToPath(urlOrPath) : urlOrPath;

import path from 'path';

path.from('/Users/sindresorhus');
//=> '/Users/sindresorhus'

path.from(new URL('file:///Users/sindresorhus'));
//=> '/Users/sindresorhus'

So basically you would like toPathIfFileURL to become public API?

node/lib/internal/url.js

Lines 1555 to 1563 in 9caceb2

	function isURLInstance(fileURLOrPath) {
	return fileURLOrPath != null && fileURLOrPath.href && fileURLOrPath.origin;
	}
	function toPathIfFileURL(fileURLOrPath) {
	if (!isURLInstance(fileURLOrPath))
	return fileURLOrPath;
	return fileURLToPath(fileURLOrPath);
	}

[fisker]

FYI: I have url-or-path published myself, and I found check protocol not that useful, and I removed recently.

[sindresorhus]

@benjamingr Yes

[sindresorhus]

So basically you would like toPathIfFileURL to become public API?

Yes

[benjamingr]

Would it be fine if the name was more explicit like path.fromURL or path.fromFileURL ?

[aduh95]

I don't think we can be much more explicit than url.toPathIfFileURL.

[github-actions]

There has been no activity on this feature request for 5 months and it is unlikely to be implemented. It will be closed 6 months after the last non-automated comment.

For more information on how the project manages feature requests, please consult the feature request management document.

[sindresorhus]

Please keep this open.

[benjamingr]

@MoLow wanna take a look?

[MoLow]

Sure, once I'm back from vacation

[khaosdoctor]

Would it be fine if the name was more explicit like path.fromURL or path.fromFileURL ?

+1 to this, the semantics seems more concise with the rest of the API

[sindresorhus]

The pull request for this issue was recently closed for lack of response from one of the reviewers.

The main open question is how file URL strings ('file:///c:/foo.txt') should be handled. Should they be normalized to a path or passed through?

I would argue they should be either passed through or even throw a user-friendly error. Node.js APIs do not seem to currently handle file URL strings and I don't think they should either:

fs.readFileSync('file:///Users/sindresorhus/x.md');
// Error: ENOENT: no such file or directory, open

[aduh95]

Node.js APIs do not seem to currently handle file URL strings

Just to clarify, it does handle it but as a relative path (i.e. in your example it tries to read ./file:/Users/sindresorhus/x.md).

[SetTrend]

This solution would particularly be useful for converting import.meta.url into a file path.

[aduh95]

This solution would particularly be useful for converting import.meta.url into a file path.

You can already use fileURLToPath(import.meta.url) for that.

[SetTrend]

Oh, sorry. Got mislead by reading as this issue is still open.

[github-actions]

There has been no activity on this feature request for 5 months and it is unlikely to be implemented. It will be closed 6 months after the last non-automated comment.

For more information on how the project manages feature requests, please consult the feature request management document.

[sindresorhus]

Please keep this open.

[MrMothman]

Is this still open to being implemented? I haven't done open source before in a meaningful way but I want to try this if I still can?

[RedYetiDev]

AFAICT this is implemented as url.pathToFileURL and url.fileURLToPath.

@nodejs/path would it be worth it to make path.toURL and path.fromURL an alias to those functions?