Timer validator disallows whitespace at the end or in the beginning

[zxuanhong]

Describe the bug

1. This cron expression is error???? Why can deployment be successful and run normally(0/1 * * * * ? )

Steps to reproduce

1. Cron expression validation exception

Expected behavior

1. Can correctly verify cron expressions

Environment

• OS: [e.g. MacOS 10.2, Windows 10] macos 15.3
• Camunda Modeler Version: [e.g. 2.0.0] 5.31.0
• Execution Platform: [e.g. Camunda 7, Camunda 8] Camunda 8

Additional context

No response

[barmac]

I am able to reproduce this issue. We are too strict when validating cron expressions.

[barmac]

This problem is present when you add whitespace to the expression, e.g.

+  * * * * * * 
- * * * * * *

The timer is successfully registered even though linting shows an error.
I can see two ways to fix it:

1. Trim the value saved in the XML
2. Change validation to accept whitespace

Is there any use case to keep the whitespace?

[barmac]

It's a small issue with little complexity. It needs to be fixed in the timer rule: https://github.com/camunda/bpmnlint-plugin-camunda-compat/tree/main/rules/camunda-cloud/timer

[nikku]

If this is about whitespace, then bpmn-io/properties-panel#309 is relevant. I do think that the rule should simply be a little bit more forgiving, and trimming whitespace (in the modeler) is a separate issue.

[barmac]

I think so. The cron expression from the screenshot that I typed manually worked fine. Only after I added the whitespace, the Modeler reported a problem.