Hank Beaver » regex

Reminder to self and world: Varnish uses POSIX regex.

hbeaver — Tue, 14 Jul 2009 19:26:45 +0000

What does this mean? Well for starters, those nice little PCRE shorthands for character classes just don’t work! So putting this in your Varnish VCL will silently do nothing:

if (req.url ~ "/\d+(/$|/\?|\?|$)") ...

whereas this match:

if (req.url ~ "/[0-9]+(/$|/\?|\?|$)") ...

Enjoy.

Realtime response time reporting from Rails logs using regex.

hbeaver — Fri, 05 Jun 2009 15:12:20 +0000

Simple but effective regex to monitor when there are issues. In my example below, this will show all response times > 1 second:

 tail -f production.log | egrep "Completed in [0-9]{3,10}"

Regex to find any divs OR spans

hbeaver — Sun, 01 Mar 2009 21:09:58 +0000

I whipped this up to remove all spans and/or divs in an HTML. Don’t ask why. Here’s the regex:

< ?(span|div)[a-zA-Z0-9'" =]+>

Did I mention I love regex?

Enjoy.

Don’t for the ‘g’ when doing regex replace in Javascript!

hbeaver — Mon, 12 Jan 2009 18:59:53 +0000

When needing to perform a String.replace() with some regex and globally replace text. You must remember to put the “g” argument like so:

var str = “‘http://www.com/123/123′”

str.replace(/’/g,”")

Spent a few minutes banging my head on this one. So remember the “g”!