How unmarshal dynamic keys

I have a yaml file with the follow structure:

mappings:
  extgroup1:
  - somescope1
  - somescope2

  someextgroup:
  - somescope3

  allusers:
  - somescope1

The mappings are basically an array, but the structure is just a dynamic set of keys. I want to unmarshall this into an array of a new data type like so:

type ExternalGroupMapping struct {
	ExternalGroup string
	Scopes        []string
}

So, it would look something like:

[]Mappings{
     ExternalGroupMapping{
         ExternalGroup: "extgroup1"
         Scopes: []string{"somescope1", "somescope2"}
     },
     ExternalGroupMapping{
         ExternalGroup: "someextgroup"
         Scopes: []string{"somescope3"}
     },
     ExternalGroupMapping{
         ExternalGroup: "allusers"
         Scopes: []string{"somescope1"}
     }
}

Similar to something like to_entries in jq

Is something like this possible? Not even sure where to begin.

Thanks!

Without custom marshaling, you can do this by mapping dynamic keys to map keys. Each mapping appear to be an array of scopes, so:

type Mappings struct {
   Mappings map[string][]string `yaml:"mappings"`
}