jMeter - Extract Value from Variable

Question

I am using jMeter to perform a stress test of a website. I need to pass a variable's value to the next Request.

The value can be seen as follows in the response body:

var _data = {};
_data["_as_csrf_token"] = "64da5d341c253c2a181796d2524e57c6502d906b";
jQuery.ajaxSetup({ data: _data, type: "POST" });

How should I use the Regular Expression Extractor to get this value?

Answer 1

The easiest way is to use boundary extractor:

Set left to:

data["_as_csrf_token"] = "

And right to:

";

If you want to use regex extractor then use:

data\["_as_csrf_token"\] = "[^"]+?";

Answer 2

The relevant regular expression would be:

_data\["_as_csrf_token"\] = "(\w+)";

Demo:

• you need to escape meta characters first
• \w is a character class for word characters (alphanumeric, case insensitive)
• + is the repitition

More information:

• Using RegEx (Regular Expression Extractor) with JMeter
• Perl 5 Regex Cheat sheet

Answer 3

Please use the following string to extract the data using ReEx Extractor.

_data\[\"_as_csrf_token\"\] \= \"(.+?)\"\;

As shown in the screenshot below In case you are worried about the data to be extracted. I would suggest using https://regexr.com/ The reason why i prefer this site is because it helps you with the cheatsheet as well.

Second question, why (.+?) why not anything else? The reason is that it matches every kind of text within the pattern. No need to worry about the special characters.