Background
I’ve decided to document this primarily for future reference.
In an app am working on, I have a database table access_points for the model AccessPoint. This table has a column phone_number which has to be unique for each access point model. This has been a pain point during testing with respect to generating unique phone numbers to a certain degree of accuracy.
The approach demonstrated below has worked best so far.
PHP Example
<?php
use App\AccessPoint;
use Faker\Generator as Faker;
use Illuminate\Database\Eloquent\Factory;
/** @var Factory $factory */
$factory->define(AccessPoint::class, function (Faker $faker) {
/**
* We use anonymous function variable assignment here to assign a function
* to the variable $randomNumber. What the function does is generate an n-digit number.
* See below Stackoverflow answer.
* @see https://stackoverflow.com/a/13169091/6924437
*
* @param $length
* @return string
*
* @see https://www.php.net/manual/en/functions.anonymous.php
*/
$randomNumber = function($length)
{
$result = '';
for($i = 0; $i < $length; $i++) {
$result .= random_int(0, 9);
}
return $result;
};
/**
* Set the initial mobile number as a random Cameroonian number.
* You can use a number from any network operator in your country here.
*/
$mobileNumber = '+237671231833';
/**
* Try generating a unique number by replacing the last 4 digits of the example phone number with 4 randomly
* generated digits.
*/
$mobileNumberUnique = substr($mobileNumber, 0, -4) . $randomNumber(4);
return [
'phone_number' => $mobileNumberUnique,
];
});
If you use Laravel you’ll notice this is a model factory. You can of course move the logic into a function as necessary for your use case.
I also had to go through the trouble of using an anonymous function variable for I don’t have to declare a function that’ll be ‘hanging’ in my codebase. Might clean up the post later, but if you need any clarification, please leave a comment.