[SLING-5389] Sling Models: Do not swallow PostConstruct exceptions

• Type: Bug
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Affects Version/s: Sling Models Impl 1.2.4
• Fix Version/s: Sling Models Impl 1.2.6
• Component/s: Extensions
• Labels: models
• Assignee: Konrad Windszus
• Reporter: Stefan Seifert
• Created: 18/Dec/15 09:49
• Updated: 28/May/20 10:20
• Resolved: 08/Jan/16 09:55

Description

SLING-4161 introduced a special handling for postconstruct errors (in ModelAdapterFactory):

    public <AdapterType> AdapterType getAdapter(Object adaptable, Class<AdapterType> type) {
        Result<AdapterType> result = internalCreateModel(adaptable, type);
        if (!result.wasSuccessfull()) {
            // treat post-construct and validation exceptions differently, because they are sometimes used for flow-control or validation purposes
            if (result.getThrowable() instanceof PostConstructException || result.getThrowable() instanceof InvalidModelException) {
                log.debug("Could not adapt to model", result.getThrowable());
            } else {
                log.error("Could not adapt to model", result.getThrowable());
            }
            return null;
        } else {
            return result.getValue();
        }
    }

that means that all exceptions that are caught in a @PostConstruct annotated method are logged only in debug level. even if it's only a NPE in the code.

this makes identifying errors in PostConstruct methods very hard. we need to come up with a better solution to differentiate between validation errors not to log as errors and real errors like an NPE.

Issue Links

• is broken by: SLING-4767 Optional sub models are logged as warn if they cannot be adapted
• is related to: SLING-8079 Returning false in a model PostConstruct causes an java.lang.IllegalStateException
• relates to: SLING-9478 Expose the full stack trace for PostConstruct exceptions
• relates to: SLING-4161 Support Sling Validation through a new field of the Model annotation