Update summary with values from other fields

[JOAQUIM MESTRES]

We use JIRA SOFTWARE in CLOUD.

We would like update values SUMMARY field with the values of other fields. 

We've used the post-function but we don't have a good result.

We use this sintax:

"El Resumen de la incidencia se actualizará a {{issue.customfield_10043}} {{issue.customfield_10044}}."

And the result is : SUMMARY = {{issue.customfield_10043}} {{issue.customfield_10044}}

We need this result: SUMMARY = PRODUCT_A CUSTOMER_A

Is it possible? 

[Nic Brough -Adaptavist-]

What scripting add-on are you trying to use to do this?

[JOAQUIM MESTRES]

None.

Must I download some complement to my JIRA CLOUD? 

[Nic Brough -Adaptavist-]

I'm afraid you do need an app to help you with this.  Jira has a little bit of automation built into it (more is being added to Cloud), but nothing that will do field manipulation to this level.  So you need an App.

I'd use Scriptrunner of course, as I work for and with people who know it.  There are a couple of other tools for Cloud that can work with fields like this.

[JOAQUIM MESTRES]

I've estudied Scriptrunner, but in Cloud version there isn't a behavior opcion to update summary field in screen. Only is possible with a trigger after insert issues.

I need see the proposed value in screen, so users can change it if they want.

[Nic Brough -Adaptavist-]

That's not going to happen on Cloud - it does not support any functionality that could pre-fill things.  If you want to set a summary automatically, you have to do it in a post-function.