[SLING-4010] Allow validator to set a custom failure message

• Type: Improvement
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Fix Version/s: Validation 1.0.0
• Component/s: Validation
• Labels: validation validator
• Assignee: Bertrand Delacretaz
• Reporter: Konrad Windszus
• Created: 07/Oct/14 18:35
• Updated: 20/Sep/17 13:17
• Resolved: 08/Oct/14 09:13

Description

Currently the Validator may only return a boolean value or an exception in case the validator was called with invalid parametrization (https://github.com/apache/sling/blob/trunk/contrib/validation/api/src/main/java/org/apache/sling/validation/api/Validator.java).

In some cases the validator could give some important information about why the validation failed. This is e.g. the cause for a reference validator where the cause for a failed validation could be:

1. referenced resource is not existent
2. referenced resource is not having the right resource type
3. referenced resource is not activated

So instead of only returning a boolean value, it should also be possible to return a failure message.