Document URL whitelist regex matching behaviour

[edmundoa]

We should clarify how URLs are matching against regular expressions in the URL whitelist.

Context

I added an entry to the URL whitelist as a regular expression http://google.com, and I expected it to match ^http://google.com$ but it matched http://google.com.* instead.

Expected Content

Since there are two different expectations on how regular expressions would match in the described example, the documentation and/or the product should explain how regular expressions will match any given URL.

Your Environment

• Graylog Version: Graylog >= 3.1.4