How to implement strong password policy in Gluu's default password reset feature

Here we are showing how we can implement a password policy so when user will reset their password, it will only take strong password.
Strong password means:

• It contains at least 8 characters and at most 20 characters
• It contains at least one digit
• It contains at least one upper case alphabet
• It contains at least one lower case alphabet
• It contains at least one special character which includes !@#$%&*()-+=^.
• It doesn’t contain any white space

Modification in attribute

We just need to apply a regular expression to impose strong password in userPassword attribute.

Regular expression will be:

• Regex Pattern: ^(?=.*[0-9])(?=.*[a-z])(?=.*[A-Z])(?=.*[!@#&()--[{}]:;',?/*~$^+=<>]).{8,20}$

Above regular expression can be modified easily to support differnt strong password policy according to own organisation.