Hi everyone. Does anyone have implemented a dynamic field update. I mean, one function that update t...

# exposed

[Vinicius Araujo]

Hi everyone. Does anyone have implemented a dynamic field update. I mean, one function that update the given property with given value (maybe with generics) ?

[tapac]

What is the use-case?

[Vinicius Araujo]

Supose I have a User table:

id
name
age

I would like to listen to a PATCH requisition with val property, val newValue and perform an update on said property`s table. like if (property == "name") then [update name], but maybe using generics instead

[tapac]

You want it on DSL level?
Like intercept any updates on some table and override a value?

[Vinicius Araujo]

What I need is somthing like this:

fun patchUser(property: String, newValue: Any) = transaction { 
    Users.update { 
        it[<property>] = newValue
    }
}

[tapac]

It looks like not very type safe approach.
Where property and newValue are come from?

[Vinicius Araujo]

You are right, it is not safe at all. It is comming from a http request. Any toughts on a good way to implement PATCH (update only a few values of the entity) requests?

[Shawn A]

You'd typically bind your patch request body to a data class or something. That gives you your type safety.

[Shawn A]

How you do that binding depends on the web framework you are using.

[Vinicius Araujo]

Thats what I thought, Maybe the best aproach is to create a model with nullable properties only to wrap patch requests, and in the transaction i check if not null, update:

fun patchUser(patchUser: PatchUser) = transaction { 
    Users.update { 
        if(patchUser.name) != null
            it[name] = patchUser.name
        if(etc...)
    }
}

[Vinicius Araujo]

Please share if there is a cleaner way to do it

[tapac]

You could use reflection but it will slower your app and will make your code less readable.