How to match https://site.com and site.com links in react app?

Question

HTML

2 links come from the database
url1 = ' https://facebook.com '
url2 = 'github.com'

<a href={props.url1}>Facebook</a> //Переходит на сайт как абсолютная ссылка
<a href={props.url2}>Github</a> //Переходит  localhost/github.com как относительная ссылка

How can I make them all absolute links, regardless of whether the link contains https:// ?

Answer 1

before displaying the link, you can check for the presence of schema and if not, do your magic.

console.log(/https?:\/\/.*?/.exec('https://github.com'));
// ["https://", index: 0, input: "https://github.com", groups: undefined]

console.log(/https?:\/\/.*?/.exec('github.com'));
// null

Answer 2

Those without https://must be with http://.