Support `to_json` function on `struct` type

[dharanad]

Is your feature request related to a problem or challenge?

This request is to support to_json in comet apache/datafusion-comet#631. Rather implementing this in comet, i think we should have this function over here and let comet rely on datafusion. Since we also support struct now, this would be a good to have feature.

to_json function Converts a column containing a structs to JSON string. We can incrementally support this functions for other types.

Describe the solution you'd like

TBD

Describe alternatives you've considered

No response

Additional context

No response

[samuelcolvin]

Maybe. Currently this crate has no logic for serialising data to JSON, just parsing JSON. So there's not much reason to put it here vs. in your package.

Still, happy to add swede here if you need it.

[dharanad]

First of all apologies for the delayed reply.

Currently this crate has no logic for serialising data to JSON, just parsing JSON.
My bad, i didn't know this.

Still, happy to add swede here if you need it.
Sorry i didn't understand, do mean serde ?

Adding the to_json feature would be a great enhancement + we can use to support comet. If you are okay to add it here, can you please guide / share your intial throught about this feature ? Just so i can have a direction to think