Flattens a map recursivelly in golang

flatten_map.go

package main

import (
	"fmt"
	"strings"
)

func flattenMap(data map[string]any, prefix string, separator string) string {
	var result []string
	for key, value := range data {
		newKey := key
		if prefix != "" {
			newKey = prefix + separator + key
		}
		switch v := value.(type) {
		case map[string]any:
			// If the value is a nested map, recursively flatten it
			result = append(result, flattenMap(v, newKey, separator))
		default:
			// If the value is not a map, append it to the result
			result = append(result, fmt.Sprintf("%s: %v", newKey, value))
		}
	}
	return strings.Join(result, "\n")
}

func main() {
	data := map[string]any{
		"user": map[string]any{
			"first_name": "silvio",
			"age":        33,
			"address":    "Rua das Ruas Ruazadas, 22",
			"family": map[string]any{
				"mother": map[string]any{
					"name": "Maria",
					"age":  60,
				},
				"father": map[string]any{
					"name": "João",
					"age":  65,
					"sons": []string{"Silvio", "Ana"},
					"parents": map[string]any{
						"grandmother": map[string]any{
							"name":    "Ana",
							"age":     85,
							"address": "Rua das Avós, 456",
							"phone": map[string]any{
								"home":   "1234-5678",
								"mobile": "9876-5432",
							},
						},
						"grandfather": map[string]any{
							"name":    "Carlos",
							"age":     90,
							"address": "Rua dos Avós, 123",
							"phone": map[string]any{
								"home":   "2345-6789",
								"mobile": "8765-4321",
							},
						},
					},
				},
			},
		},
	}

	// Call the flattenMap function and print the result
	result := flattenMap(data, "", "_")
	fmt.Println(result)
}