[feature] linter
When reloading the configuration file Jenkins can become unstable or worse not working anymore du to unrecognised properties.
It should be great to add a linter page that by copy pasting a config file checks the properties on the current Jenkins instance without applying them nor saving.
Also I suggest to use the linter when the reload is called manually using the button and when Jenkins is starting before applying the configuration.
Would be nice. Generally I would prefer to have a REST API for that an maybe a Maven Plugin which allows checking it against a running instance or against a bundled Mock instance
a linter is part of the tooling we are considering as follow-up JEP for JEP-201
this one could detect use of deprecated / restricted attributes and give guidance on how to fix this (by listing valid attribute, I don't think we can offer much as @Deprecated doesn't offer a link to replacement code.
I wrote an issue that is related to this: Refactor ConfigurationAsCode to enable clear error messages #488