longurl | This library can be used to expand short URLs such as https | Parser library

Supposing an URL always start with http and can not have an empty space, a solution would be:

http[^ ]+

[^ ]+ will match one or more non white-space characters.

You can use Node.js core module http to make an http request from within your Node application. You can consult the official documentation and various options here https://nodejs.org/api/http.html#http_http_request_options_callback

If you use throw new or return you do not need the else condition because the method ends like

You might want to look at the ASCII table. The digit 0 start at index 48, the letter A at 65 (which is 55+10) and the letter a at 97 (which is 61+36). This is just a fancy way to initialize the myChars array with the digits and letters to use.

One of the features of spring-boot-starter-parent is that it manages versions of many common dependencies for you, ensuring that the versions of all the different pieces you're using are compatible. In this case, your explicit version is causing incompatibility between Spring Data MongoDB and the MongoDB driver; simply eliminate the version tags from your dependencies.

(You may be getting a warning about "overriding managed dependency version"; always pay attention to warnings.)

What makes you think it is unexpected? This is essentially a temporary redirect response; the intent here may be twofold:

1. to allow google to edit the URLs and have that work, without browsers and other things (proxies etc) ignoring all further checks (ignoring some is fine - the point is not to cache too aggressively)
2. to allow better hit-counting, by not having browsers and other things (proxies etc) not letting most of the requests hit google

Note that 307 ("Temporary Redirect") and 302 ("Found") have the same semantics, other than what to do about the HTTP method; 307 explicitly retains the original HTTP method ("POST", "GET", etc); 302 does not. In effect, this means that goo.gl is saying "temporary redirect, and you should feel free to do a "GET", regardless of what you did originally". Note that 301 ("Moved Permanently") and 308 ("Permanent Redirect") have the same duality, but for non-temporary redirects.

MongoUrlRepository supposed to be an interface, that's the way Spring could manage it's crud implementations automatically. Since you are declaring it as a class you basically overriding the builtin finder methods to just return null, that's where your NPE is coming from.

see the examples from spring.io: https://spring.io/guides/gs/accessing-data-mongodb/

Why it worked in the 1st case:

Your variable $link is not array so it takes only last assigned value of $link. You can replace preg_replace with str_replace and pass arrays with matches and links.

You can also use preg_replace_callback() and you can pass $matches directly to function which will replace with link. https://stackoverflow.com/a/9416265/7082164