Scripting Exercise: Unique Usernames

The quickest and easiest solution to this problem would be to create a big list of unique usernames and keep track of which ones have been used. This is going to be painful if you have do months of testing before the database is refreshed, so it is good if you can find a code-based solution.

Note that I would be overjoyed if someone can provide a better solution than the one that I have provided.

1. using a random number will not work as it is not guaranteed that it will not create duplicates.
2. using the “unique” parameter type will not work as it is only guaranteed to be unique during a single test run.
3. a date/timestamp combined with a vuser ID or unique number parameter type would satisfy the requirement for no duplicates, but would exceed the maximum number of characters (even if you got sneaky and used a Julian date format)
4. see my solution here

I agree that creating usernames outside of LoadRunner (using Excel or whatever) is quick and easy when you’ve only got a few tests to run.

I would argue that having to keep track of which usernames have been used becomes increasingly painful the more tests you have to run.

Also, I hate having to update values in a data table every time I need to run a script.

Spending 30 minutes writing some code that will save you having to manually manage a list of usernames seems like a good trade-off to me.

Cheers,
Stuart.

The fastest and easiest way is just record and replaying the “Create New User Account” flow for 100 iteration with different user name.

Note: Just parameterize the name with a list of values dragged from an excel.

Cheers,
Senthil

I agree with Stuart’s solution to create unique names. I also used this way in the past and it works.

Alternatively, you can also do the following:
Define year, month, day,hour, and seconds array with pre-defined charactors.
eg.
char arrayYY[8][1]=”{“a”,”b”,”c”,”d”,”e”,”f”,”g”,”h”};
char arrayMM[12][1]=”{“a”,”b”……..”}
.
.
.
char arraySeconds[60][2]={“AA”,”AB”,…..”};// 60 of them

Then, read out the real time value of dates and select the characters from the array.
eg.
yy=atoi(lr_eval_string(“{TimeYear}”) // defined parameter
yy=yy-7 // can be randomised
.
.
.
sec = atoi(lr_eval_string(“{TimeSecond}”);

Next part of concatenating will be similar to Stuart’s solutions.
eg.
strncat(SecondName, arraySeconds[sec],2)
.
.
lr_save_string(SecondName,”SecondNameParam”);

likewise
strncat(FirstName, arraryMM[mm], 1);

lr_save_string(FirstName,”FirstNameParam”);

…..
Anyway, this alternative solution I hinted out may be a bit longer in code.
One of the main advantage of using this as I found is to use the pre-defined characters by yourself.

Cheers
Mohan

Hi

Your unique username code is quite clever – thanks. I have modified it because when I used today’s date, 20 Jan, it returned a 4-char value (supressed zero). My change forces a leading zero.

Action1()
{

char buf[6]; // this buffer is used to hold the converted date value (forced 5 chars).
char buf_tmp[6]; // this temp buffer is used to hold the converted date value (max 5 chars).
int datetime; // temporary variable to hold the integer representation of the current data/time.
int rc;

/*
Userame must start with a letter, and must end with a unique number.
Let’s use “t” to indicate that it is a test user, and use a 2-digit Vuser ID (maximum of 99 users in the scenario). Both of these
attributes will be helpful when searching for usernames that have been created during the test.
This leaves 5 characters to play with.

Let’s use a date/time stamp, and convert it to base36 so that we do not exceed our character limit.

Date does not have to include the year, as the test database will be refreshed at least yearly,
and the time does not have to include seconds, as it is not possible for a user to complete an iteration in less than 1 minute.

The date/time stamp value will therefore be “mm dd hh mm” (biggest number will be: 12 31 23 59 – note that this
will comfortably fit inside an integer).

This is clearly going to be longer than 5 characters, so convert it to base 36 (http://en.wikipedia.org/wiki/Base_36).

The biggest possible value will fit into a 5-digit base36 number (7bw9z).

*/

// %m month number (01-12)
// %d day of month (01-31)
// %H hour (00-23)
// %M minute (00-59)
lr_save_datetime(“%m%d%H%M” , 0, “DateTimeParam”);
lr_output_message(“DateTimeParam: %s”, lr_eval_string(“{DateTimeParam}”));

// Save the date/time value to an integer so that it may be converted to a different base.
datetime = atoi(lr_eval_string(“{DateTimeParam}”));
// A date of 01201858 returns a 4-char itoa value
// datetime = 1201858; // for debugging, use this to return 4 char date time in itoa call
// datetime = 11201858; // for debugging, use this to return 5 char date time in itoa call

// Convert to base 36 and save output to buffer.
itoa(datetime, buf_tmp, 36);

// Force 5 char string
sprintf(buf, “%05s”, buf_tmp);

// Save the converted value back to a parameter.
lr_save_string(buf, “ConvertedDateTimeParam”);

// Create the final unique username parameter.
lr_save_string(lr_eval_string(“T{ConvertedDateTimeParam}{pVuserID}”), “UniqueUsernameParam”);

// Output the unique username.
lr_output_message(“Unique username: %s”, lr_eval_string(“{UniqueUsernameParam}”));

return 0;
}

There are possibilities and there are probabilities. It is possible, academically, you will have 3844, i.e. 62×62, users signing up in the same second. The probability, in most real life situations however, is quite low. So, if you just use the time.(count % 3844), you can always have exactly 8 characters for the unique user name.

hello,

We are talking about the Correlations first.

but what i saw over here is you guy are talking about paramerazation

i think correlation and paramerazation are two different things in load runner,

Can anybody explain me how to do manuall correlation?