Set value to custom field from issue Summary

[Aynur]

Hi, dear all,

I need to create an automation which will manage to set a value to the "customers"  custom field from summary. If the the entry of summary does not exist in customers, then it will be added to it.

My question is what is the best way to set up it by script action in automation or is there an effective way? 

If I choose script action, how I can check the value of summary exists in customers custom field?

Thanks in advance

Best regards,

Aynur