Create a complex login password for rackspace mail api

create-email-password-for-rackspace-mail.php

<?php
/*
Create a complex 8 character password which meets (exceeds actually) the rackspace mail requirements.

Author: craig@123marbella.com ON 27/9/2017

This function allows you to specify the length of the password and the specific characters to include in the password.

Compleletly random passwords look ugly, so this function will build the password into a random and complex, yet friendlier looking password. 

EG: Man$6256 or Lin%9082

This is expecially useful if you need to give the password to a client over the phone or read the password out.

You can meet ALL the following requirements with this function:

At least 8 characters long 
One lowercase character 
One uppercase character 
One number 
One non-alphanumeric character (!, $, #, %, etc)
NO sequential numbers (EG: 123 or 456 or 789 etc)

NOTE: passwords should always be as long as possible, not just 8 chars! But this password is a starting pinit for clients.

*/
function create_rackspace_mail_email_password() {

	//generate the first part of the password for the user
	//to avoid readibility issues for end users, avoid using 0,i,l
	$length = 4;
	$chars = "abcdefghjkmnpqrstuvwxyz";
	$first_part = substr(str_shuffle($chars),0,$length);
		
	//generate the second part of the password for the user
	//add more non-alphanumeric characters to $chars if you want
	//I suggest only adding the more common ones as on mobile 
	//and foreign keyboards its sometimes hard to find the symbols.
	$length = 1;
	$chars = "$#%!";
	$second_part = substr(str_shuffle($chars),0,$length);
		
	//generate the third part of the password for the user
	//to avoid sequential numbers, use: 02468 for $chars
	$length = 3;
	$chars = "02468";
	$third_part = substr(str_shuffle($chars),0,$length);
		
	//join all togther to form password and capitalise the first letter
	return ucfirst($first_part . $second_part. $third_part);
	
}