Value Changed Tag Event Data Quality

[PGriffith]

Some general advice:

User object functions

Unfortunately, at some level (and it’s easy to do, so there’s no real way to tell you exactly when it will be) you “break out” of the expected areas where we’ve documented things and end up in the base Java classes that we’re using internally. Jython automatically wraps these up so they mostly seem like Python objects, so it’s hard to tell exactly when you get there. What I generally recommend, if you’re encountering something unfamiliar and want to see what you can do with it: Start with run…

More specifically:
Printing the type of currentValue.quality (literally, just print type(currentValue.quality) will probably give you something like com.inductiveautomation.ignition.common.sqltags.model.types.DataQuality - the name of the Java class in our codebase. While I'd highly recommend the introspection tools I outline in the above post, you can also just go straight to the reference material (for example: ignition 7.9.5 API) and just look for DataQuality there. You'll see that this class implements the underlying Quality interface, which is where the isGood() method is actually defined.