Convert a flat yaml file with property names that have dots in them to a nested structure

yaml-nest.go

package main

import (
	"log"
	"os"
	"strings"

	"gopkg.in/yaml.v2"
)

func nestProperties(originalData *map[interface{}]interface{}, prefix string) map[interface{}]interface{} {
	interiorProps := make(map[string]bool)
	retVal := make(map[interface{}]interface{})
	for keyIntf := range *originalData {
		key, _ := keyIntf.(string)
		if prefix != "" && !strings.HasPrefix(key, prefix) {
			continue
		}

		key = strings.TrimPrefix(key, prefix)
		if strings.Contains(key, ".") {
			interiorNode := strings.SplitN(key, ".", 2)[0]
			interiorProps[interiorNode] = true
		} else {
			retVal[key] = (*originalData)[prefix+key]
		}
	}

	for key := range interiorProps {
		retVal[key] = nestProperties(originalData, prefix+key+".")
	}

	return retVal
}

func main() {
	initialData := new(map[interface{}]interface{})
	decoder := yaml.NewDecoder(os.Stdin)

	if err := decoder.Decode(initialData); err != nil {
		log.Fatal(err)
	}

	nestedData := nestProperties(initialData, "")
	encoder := yaml.NewEncoder(os.Stdout)
	if err := encoder.Encode(nestedData); err != nil {
		log.Fatal(err)
	}
}