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  1. package main
  2.  
  3. import (
  4. 	"fmt"
  5. 	"reflect"
  6. )
  7.  
  8. type Config struct {
  9. 	AppName string `json:"app_name"`
  10. 	Port    int    `json:"port"`
  11. 	Debug   bool   `json:"debug"`
  12. }
  13.  
  14. // LoadConfigFromMap loads configuration from a map[string]interface{}
  15. func LoadConfigFromMap(cfg interface{}, data map[string]interface{}) {
  16. 	v := reflect.ValueOf(cfg).Elem()
  17. 	for key, value := range data {
  18. 		field := v.FieldByName(key)
  19. 		if field.IsValid() && field.CanSet() {
  20. 			if field.Kind() == reflect.Ptr {
  21. 				if field.IsNil() {
  22. 					field.Set(reflect.New(field.Type().Elem()))
  23. 				}
  24. 				field = field.Elem()
  25. 			}
  26.  
  27. 			valueType := reflect.TypeOf(value)
  28. 			if field.Kind() == valueType.Kind() {
  29. 				field.Set(reflect.ValueOf(value))
  30. 			} else if field.Kind() == reflect.Struct {
  31. 				// Recursively call LoadConfigFromMap if the field is a struct
  32. 				LoadConfigFromMap(field.Addr().Interface(), value.(map[string]interface{}))
  33. 			}
  34. 		}
  35. 	}
  36. }
  37.  
  38. func main() {
  39. 	cfg := &Config{}
  40. 	configData := map[string]interface{}{
  41. 		"app_name": "MyApp",
  42. 		"port":     8080,
  43. 		"debug":    true,
  44. 		"db": map[string]interface{}{
  45. 			"host": "localhost",
  46. 			"port": 3306,
  47. 		},
  48. 	}
  49.  
  50. 	LoadConfigFromMap(cfg, configData)
  51.  
  52. 	fmt.Printf("%#v\n", cfg)
  53. }
Success #stdin #stdout 0s 5288KB
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&main.Config{AppName:"", Port:0, Debug:false}
https://ideone.com/dWlObA
422808_turn2_modelB_codeExecution
language:
Go (go 1.12.1)
created:
10 days ago
visibility:
public

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