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Valid HTTP URL


lib/utils.js
export const isValidHTTPUrl = (string) => {
	let url;

	try {
		url = new URL(string);
	} catch {
		return false;
	}

	return ['http:', 'https:'].includes(url.protocol);
}

We are using the URL API to check if a passed string is valid or not.

The first try/catch will immediately catch if the string is a valid URL or not, if it is not, it will throw an error like Uncaught TypeError: URL constructor: string is not a valid URL. In such a case, we would return false in the catch block

In case it's a valid URL, the last line checks if it's a valid HTTP/HTTPS URL.

Note: This method has no false negatives (as far as I know) but does have some false positives

Some examples of false positives could be http://.. or http:/a which are considered valid URLs, even though the DNS might not resolve for these URLs, you can read the RFC 3986 for more details.

Nevertheless, I would prefer to use this over the complex Regex which could potentially break the internet

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