Regex Pattern Matching in LoadRunner

I quite literally stole this idea from Charlie at PerformanceEngineering in which he posted a response to a challenge by Dmitry on how to get regular expressions up and running within LoadRunner.

I’m a huge fan of regex, and thanks to these guys, now have a way of implementing at least pattern matching with LoadRunner. Ideally I’d like to be able to include pattern matching & replacing, like Ruby or Perl does in one line but for now am happy for pattern matching.

Read on for the changes I made to Charlies code to abstract matching functionality and call it as a function within other LoadRunner actions.

First thing, follow these instructions posted by Charlie

# First, download the Binaries and Developer Files for PCRE (Perl Compatible Regular Expressions):
http://gnuwin32.sourceforge.net/pakages/pcre.htm

# Unzip (both archives) into c:\pcre

# Modify c:\pcre\include\pcre.h by commenting out the include for stdlib.h:

//#include <stdlib.h>

# In your LoadRunner script, add to globals.h:

#include "c:\\pcre\\include\\pcre.h"

Then from here on I differ slightly by adding a couple of functions to my vuser_init as per the following:

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vuser_init()
{
    return 0;
}
 
buffer()
{
	// This will save a 2MB buffer of the response body when called.
	web_set_max_html_param_len("2097152"); //2MB buffer
	web_reg_save_param("buffer", "LB=", "RB=", "Search=Body", LAST);
	return 0;
 
}
 
match(const char *string, char *pattern)
{
	// This will return 1 for a match, or 0 for a non-match / error
	int status;
	pcre *re;
	lr_load_dll("c:\\pcre\\bin\\pcre3.dll");
 
	if (regcomp(&re, pattern) != 0) {
		return(0); /* Report error. */
	}
	status = regexec(&re, string, (size_t) 0, NULL, 0);
	regfree(&re);
	if (status != 0) {
		return(0); /* Report error. */
	}
	return(1);
}

Then from your main action you can call that match function in a Perl’ish kind of way as per:

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rc = match(lr_eval_string("{buffer}"),"[\\w-]+");
lr_message("Return Code = %d",rc);

Make sure you create an int to store your return code.
Attached are example vuser_init and actions for you.
regex vuser_init :: regex action

Thanks Charlie and Dimitry! Would like to see this challenge extended to search & replace functionality using regex …