DateStringConverter should convert empty String to null Date

[gusehr]

Expected Behavior

IMHO, when my node have an empty property mapped to a Date field, the DateStringConverter should return a null Date object.

What dou you think?

Current Behavior

When my node have an empty property mapped to a Date field, the DateStringConverter throws an exception because it tries to parse the empty String.

Your Environment

• OGM Version used: 3.0.0
• Java Version used: 1.8
• Neo4J Version used: 3.2.3
• Bolt Driver Version used (if applicable): 3.0.0
• Operating System and Version: Ubuntu

[nmervaillie]

Do you mean a non existing property or a property containing an empty String ?

[gusehr]

Hi @nmervaillie I mean a property containing an empty String.

[nmervaillie]

I'm mixed about this because an empty string might be a symptom of an error in a previous saving / import, and hiding this wouldn't fix the root cause. I usually like fail fast.

But I guess it depends on the use case. Can you tell a bit more about yours ?

Maybe we could add an attribute to the annotation strictMode=true/false.

[jasperblues]

While fail fast quickly communicates that something is wrong, if its a choice between two behaviors, I prefer the OGM to be forgiving:

• Easier to get up and running quickly on a legacy database.
• Migrating to OGM gradually. If there's another system that's using empty strings for no value (it happens) it needs to be fixed before OGM can be used. Not always realistic.

[gusehr]

@nmervaillie My use case is actually a data import, and I can't change the data source. I can workaround this issue creating my own Converter, but I think that this could be the default behavior.

I know that from a "strict" point of view, the empty String should communicate an error. But from a "practical" point of view, the empty String represents a null Date.

An annotation configuration can solve the issue.

@jasperblues I agree that the default behavior should be less strict and more lenient.

[meistermeier]

We discussed this and have come to the conclusion that we want to keep the current behaviour but add a property (lenient) to the string-based annotation currently available (@DateString, @NumberString and @EnumString). In the current version this will handle blank strings as null values when reading those from the database.