feat: add ability to create a File object from URL

[ddelgrosso1]

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Fixes #1898 🦕

[danielbankhead]

Looks great! One optional suggestion

[danielbankhead]

Alternatively, we could parse the URL, then use protocol to determine the logic. Here's an example with an optional storage param:

Suggested change

	static from(
	publicUrlOrGsUrl: string,
	storageInstance: Storage,
	options?: FileOptions
	): File {
	const gsMatches = [...publicUrlOrGsUrl.matchAll(GS_UTIL_URL_REGEX)];
	const httpsMatches = [...publicUrlOrGsUrl.matchAll(HTTPS_PUBLIC_URL_REGEX)];
	if (gsMatches.length > 0) {
	const bucket = new Bucket(storageInstance, gsMatches[0][1]);
	return new File(bucket, gsMatches[0][2], options);
	} else if (httpsMatches.length > 0) {
	const bucket = new Bucket(storageInstance, httpsMatches[0][2]);
	return new File(bucket, httpsMatches[0][3], options);
	} else {
	throw new Error(
	'URL string must be of format gs://bucket/file or https://storage.googleapis.com/bucket/file'
	);
	}
	}
	static from(
	publicUrlOrGsUrl: string | URL,
	storage?: Storage,
	options?: FileOptions
	): File {
	const url = new URL(publicUrlOrGsUrl);
	if (url.protocol === 'gs:') {
	const storageInstance = storage ?? new Storage();
	const bucket = new Bucket(storageInstance, url.host);
	return new File(bucket, url.pathname.slice(1), options);
	} else if (url.protocol === 'http:' || url.protocol === 'https:') {
	const {groups: {bucketName, fileName}} = /\/(?<bucket>[^/]*)\/(?<filename>.*)/.exec(u.pathname);
	const storageInstance = storage ?? new Storage({apiEndpoint: url.hostname});
	const bucket = new Bucket(storageInstance, bucketName);
	return new File(bucket, fileName, options);
	} else {
	throw new Error(
	'URL string must be of format gs://bucket/file or https://storage.googleapis.com/bucket/file'
	);
	}
	}

If we do this we'll need to make a small change to storage.ts on line ~180 to prevent accidental custom apiEndpoint when provided.
From:

if (options.apiEndpoint) {

To:

if (options.apiEndpoint && options.apiEndpoint !== apiEndpoint) {

[ddelgrosso1]

Good suggestion, I'm apt to leave this using the regexs to make it a bit more concise and avoid the apiEndpoint logic. It also matches how it was done in the python client (not that consistency is SUPER important).

[shaffeeullah]

let's gooooo 🚀 so excited to see this feature get implemented!
appreciate you @ddelgrosso1 & @danielbankhead !!