JsonNode throws "Type must not be Null" on Spring Boot+datastore project when Jackson us upgraded to 2.14.X or higher

[jevanio]

Hey folks,
I been working on a spring boot project which use Datastore as backend. On this project, I'm trying to update jackson dependencies from the current version it has (2.13.4) to a newer one (2.16.2) but I been having an issue on a Datastore Entity which use JsonNode as attribute.

I have seen that, after upgrading to jackson 2.14.X or higher, I'm getting an error on bean creation which only says "Type must not be null". After a lot of debugging, and creating a SpringBoot+Datastore project from scratch, I found that if I remove a JsonNode attribute from a Datastore Entity the service starts. I must mention that this JsonNode attribute has been included from long time ago and it was working.

My guess is, after Jackson upgrade to 2.14.X, there's some dependency which needs to be provided to keep it working but I haven't been able to identified which is. I review the Release Notes from 2.14.0 but didn't found anything about it.

Can you point me if there's a breaking change between 2.13.X and higher version or if a similar issue has been identified which can guide me?

[JooHyukKim]

You can refer to the release notes to find out what changed

[JooHyukKim]

I'm getting an error on bean creation which only says "Type must not be null".

Also, we need to know how the mentioend bean creation works. Minimal reproduction with only jackson related code and POJOs only would help debugging. Due to nature of this problem SpringBoot + Datastore + Jackson we can't tell how it is exactly used..

Folks at Datastore would know...how this called Datastore (library, framework?) is using Jackson, or which Jackson module (there is several)

[jevanio]

Thanks for your reply @JooHyukKim
Let me share with you a demo project which use Spring Boot + Datastore which can help on debugging: https://github.com/jevanio/demoProject
To replicate the error, the only requirement is to replace jackson version defined on the pom from 2.13.4 to 2.14.0 (or higher).

About the bean creation, this project just define the datastore entity, datastore repository and autowire it from a service

Thank in advance for any advice you can give

[JooHyukKim]

As I said above minimal reproduction with only jackson related code and POJOs would allow others to give help, not a whole SpringBoot project which is too much for anyone to spend time to pull and build locally 🤔.

[jevanio]

Actually, that's what I did.
If you check the project you will see it only have 4 classes without any logic besides to autowire a datastore repository, as it was shown on the previous comment, and include a JsonNode attribute on a Datastore Entity, as you can see on this image.

[cowtowncoder]

@jevanio Ok this is problematic in that handling of @Entity would be outside Jackson. So it'd be necessary to see what data source (?) framework does. I am guessing it perhaps enables "Default Typing" (automatic polymorphic handling), but that is just speculation.

What is needed is to see code for setting up, configuring ObjectMapper, and invocation of methods (readValue() / writeValue() ? ).

[cowtowncoder]

There are no additional dependencies for jackson-databind in 2.14 or later so missing dependency is not the root cause.

So, yeah, what would be needed is a reproduction.

On release notes; changes would be in jackson-databind section for:

• https://github.com/FasterXML/jackson/wiki/Jackson-Release-2.14 (2.13 -> 2.14)
• https://github.com/FasterXML/jackson/wiki/Jackson-Release-2.15 (2.14 -> 2.15)
• https://github.com/FasterXML/jackson/wiki/Jackson-Release-2.16 (2.15 -> 2.16)

but it sounds like you may already have gone over some of these.

[JooHyukKim]

Just out of curiosity, have u tried inquiring to Datastore team? @jevanio

[JooHyukKim]

I suggest inquiring Stackoverflow or Datastore team, because....

1. There is still no clue on how exactly JsonNode is "used".
2. Jackson does not break on initialization, straight up, so could be something wrong dependency management or misconfiguration

[cowtowncoder]

Yeah, at this point there really is little Jackson project can do, not seeing underlying exception, stack trace, or set up of Jackson components.

And even requiring that --add-opens seems to be something Datastore team would need to address.

[jevanio]

Thanks folks for your comment.
I have already made this same question on Datastore side to get their insights. Really hope they can also guide on this error :)

[cowtowncoder]

Good luck @jevanio let's hope they can help!