derlin
8/16/2016 - 9:11 AM

Golang utility to transform a struct to a map with keys in lowercase. Useful to map struct to json (uppercase names always make me blink).

Golang utility to transform a struct to a map with keys in lowercase. Useful to map struct to json (uppercase names always make me blink).

golang_mapKeysToLowerFirst.go
content_copyfile_download
// see https://play.golang.org/p/6YD4YdvGLr 
// for an example

import (
	"reflect"
	"unicode"
	"unicode/utf8"
)


func structToLowerFirstMap(in interface{}) map[string]interface{} {
	v := reflect.ValueOf(in)
	vType := v.Type()

	result := make(map[string]interface{}, v.NumField())

	for i := 0; i < v.NumField(); i++ {
		name := vType.Field(i).Name
		result[lowerFirst(name)] = v.Field(i).Interface()
	}
	
	return result;

}

func lowerFirst(s string) string {
	if s == "" {
		return ""
	}
	r, n := utf8.DecodeRuneInString(s)
	return string(unicode.ToLower(r)) + s[n:]
}