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

# 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:

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31

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:

1 2	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 …

Tim Koopmans | April 17th, 2008 | Tags: loadrunner | Category: 90kts, Altentee

7 comments to Regex Pattern Matching in LoadRunner

• Sameh

  April 17th, 2008 at 10:58 am

  Thats awesome Koops…

• Dmitry Motevich

  May 2nd, 2008 at 12:15 am

  Hello, Tim.

  I appreciated your efforts on working with Regular Expressions in LoadRunner.

  I moved forward Charlie’s and your ideas on LoadRunner RegExps. So, now we can use LR RegExp to match subpatterns and to capture (=to extract) all matched substrings.

  The solution is located here:
  Examples on LoadRunner Regular Expressions

• Tim

  July 14th, 2008 at 5:00 pm

  For my own reference, you can also get regex pattern matching with this approach. You need to comment out //#include in the pcreposix.h header for this to work:

  request_num() {
  int  status;
      int  eflag;
      char buf[256];
  char out[128];
  char *pattern = "requestnum=(\\d+)'|requestnum=(\\d+)&";
  //char *pattern = "sen(\\w+)|s\\wn(\\w+)";
  char *string  = lr_eval_string("{request_num_buff}");
      regex_t re;
      regmatch_t pmatch[128];
  lr_load_dll("c:\\pcre\\bin\\pcre3.dll");
   
  if((status = regcomp(&re, pattern, REG_EXTENDED))!= 0){
  regerror(status, &re, buf, 120);
  exit(2);
      }
   
  if(status = regexec( &re, string, 10, pmatch, eflag)== 0){
  strncpy(out, string + pmatch[1].rm_so, pmatch[1].rm_eo - pmatch[1].rm_so);
          lr_save_string(out, "requestnum");
  lr_output_message("Notify: Parameter requestnum was found: %s\n",out);
  eflag = REG_NOTBOL;
      }
      regfree(&re);
  }

  Regards,
  Tim Koopmans

• David Burke

  January 7th, 2009 at 10:06 am

  Tim,

  I found the pcre files at the following site:

  http://gnuwin32.sourceforge.net/packages/pcre.htm

• Satish

  August 21st, 2009 at 12:15 pm

  Hi, I want to encrypt the password while passing these parameterized values within the script. I am basically looking to find if we have a similar function in LoadRunner (as we have in QTP, SetSecure (“test123″))?
  Appreciate, if anyone can respond.

  Thanks!

• Tim

  August 21st, 2009 at 12:57 pm

  Hi Satish, check out the lr_decrypt function, this is probably what you are after …

  Cheers,
  Tim

• Headwired » Blog Archive » Using Regular Expressions in LoadRunner

  February 10th, 2010 at 11:26 pm

  [...] been identified how to enable Regular Expressions in LoadRunner. A big thanks to Charlie, Tim for getting this working, and Dmitry for proposing the [...]

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