go-blocks/binding/binding.go

84 lines
1.8 KiB
Go

package binding
import (
"errors"
"net/http"
"reflect"
"strconv"
)
type FormBinding struct{}
func (FormBinding) Bind(r *http.Request, obj any) error {
if r == nil {
return errors.New("request is nil")
}
if err := r.ParseForm(); err != nil {
return err
}
if r.Form == nil {
return errors.New("form is nil")
}
return mapForm(obj, r.Form)
}
func mapForm(obj any, form map[string][]string) error {
val := reflect.ValueOf(obj)
if val.Kind() != reflect.Ptr || val.IsNil() {
return errors.New("obj must be a non-nil pointer")
}
val = val.Elem()
if val.Kind() != reflect.Struct {
return errors.New("obj must be a pointer to a struct")
}
typ := val.Type()
for i := 0; i < val.NumField(); i++ {
field := val.Field(i)
fieldType := typ.Field(i)
formTag := fieldType.Tag.Get("form")
if formTag == "" {
formTag = fieldType.Name
}
if values, ok := form[formTag]; ok && len(values) > 0 {
value := values[0]
switch field.Kind() {
case reflect.String:
field.SetString(value)
case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64:
intValue, err := strconv.ParseInt(value, 10, 64)
if err != nil {
return err
}
field.SetInt(intValue)
case reflect.Uint, reflect.Uint8, reflect.Uint16, reflect.Uint32, reflect.Uint64:
uintValue, err := strconv.ParseUint(value, 10, 64)
if err != nil {
return err
}
field.SetUint(uintValue)
case reflect.Float32, reflect.Float64:
floatValue, err := strconv.ParseFloat(value, 64)
if err != nil {
return err
}
field.SetFloat(floatValue)
case reflect.Bool:
boolValue, err := strconv.ParseBool(value)
if err != nil {
return err
}
field.SetBool(boolValue)
default:
return errors.New("unsupported field type")
}
}
}
return nil
}