feat: add custom NullValueSerializer initializer

[AnneMayor]

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resolved #2878

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[AnneMayor]

I'm looking for another great solution and trying to apply it.

[AnneMayor]

Please, review it. Thanks :)

[mp911de]

Thanks for looking into this enhancement. Taking a step back from the actual thing we want to solve, we have a growing number of constructors (6 constructors already). Adding another one is weakening the design. I would suggest creating a builder that accepts ObjectMapper, JacksonObjectReader, JacksonObjectWriter, and classPropertyTypeName for typing information. Also, we should add registerNullValueSerializer (boolean) for more flexibility.

That way, we can hide customization in the builder and allow further configuration options without stretching the number of constructors.

Let me know whether this makes sense.

[AnneMayor]

@mp911de Thank you for the detailed review! I think that's a great idea too. I am gonna create a new Builder class as you suggested within this weekend:) Thanks 👍

[AnneMayor]

@mp911de I created Builder class. Please, review it :D

[mp911de]

Thank you for your contribution. That's merged, polished, and backported now. You might be interested in the polishing commit 8357c7d88b4e7ee6d8bb73f1a38e602c11ff758c that refines the builder API to accept parameter-by-parameter instead of requiring all elements upfront to ease with usage experience. Let me know if you have any questions.

[injae-kim]

Polishing commit https://github.com/spring-projects/spring-data-redis/commit/8357c7d88b4e7ee6d8bb73f1a38e602c11ff758c is really awsome 👍

Thank you for kind&rapid review! (I'm friend of @AnneMayor and helping her to contribute on open source 😃)

[AnneMayor]

@mp911de , Thank you so much for your kind and rapid review 😊 I am very happy to contribute this open source. I am going to look into your polishing commit and learn from it. Again, thanks a lot 👍 @injae-kim he is a great supporter to help me to contribute. Without him, I might be unable to merge the PR so fast. Thank you for your kind support, @injae-kim 👍 You're the best!