Mapstructure tags are ignored on slice struct items

[Thiht]

I'm trying to convert a struct to a map, and can't figure out how to make it work.

Basically I have these structs:

type SQLStepResult struct {
	Queries []QueryResult `mapstructure:"queries"`
}

type QueryResult struct {
	Rows []map[string]any `mapstructure:"rows"`
}

and I want to convert SQLStepResult to:

{
  "queries": [
    {
      "rows": [
        // ...
      ]
    }
  ]
}

But I always end up with Rows instead of rows.

I tried using the undocumented mapstructure.RecursiveStructToMapHookFunc but it doesn't appear to do anything

Is there a solution?

Go playground for reference: https://go.dev/play/p/ZlTOw1mqnH5

[Thiht]

I think something needs to be done to handle slices/arrays here: https://github.com/go-viper/mapstructure/blob/main/mapstructure.go#L1008

I'll try to look into it but will probably need some help, the code is hard

[sagikazarmark]

Hm, that looks like a bug. I don't have a solution from the top of my head. I'll try to look into it when I find the time.

[wazir-ahmed]

This is related to mitchellh#249. PR mitchellh#314 has a solution. It would be great if the solution in the PR is ported to this repo and merged.