mirror of https://github.com/go-gorm/gorm.git
72 lines
1.9 KiB
Go
72 lines
1.9 KiB
Go
|
package gorm
|
||
|
|
|
||
|
|
import (
|
||
|
|
"errors"
|
||
|
|
"fmt"
|
||
|
|
"reflect"
|
||
|
|
)
|
||
|
|
|
||
|
|
func Preload(scope *Scope) {
|
||
|
|
// Get Fields
|
||
|
|
var fields map[string]*Field
|
||
|
|
if scope.IndirectValue().Kind() == reflect.Slice {
|
||
|
|
elem := reflect.New(scope.IndirectValue().Type().Elem()).Elem()
|
||
|
|
fields = scope.New(elem.Addr().Interface()).Fields()
|
||
|
|
} else {
|
||
|
|
fields = scope.Fields()
|
||
|
|
}
|
||
|
|
|
||
|
|
if scope.Search.Preload != nil {
|
||
|
|
for key := range scope.Search.Preload {
|
||
|
|
for _, field := range fields {
|
||
|
|
if field.Name == key && field.Relationship != nil {
|
||
|
|
results := makeSlice(field.Field)
|
||
|
|
relation := field.Relationship
|
||
|
|
primaryName := scope.PrimaryKeyField().Name
|
||
|
|
|
||
|
|
switch relation.Kind {
|
||
|
|
case "has_one":
|
||
|
|
sql := fmt.Sprintf("%v IN (?)", scope.Quote(relation.ForeignKey))
|
||
|
|
scope.NewDB().Find(results, sql, scope.getColumnAsArray(primaryName))
|
||
|
|
case "has_many":
|
||
|
|
sql := fmt.Sprintf("%v IN (?)", scope.Quote(relation.ForeignKey))
|
||
|
|
scope.NewDB().Find(results, sql, scope.getColumnAsArray(primaryName))
|
||
|
|
case "belongs_to":
|
||
|
|
scope.NewDB().Find(results, scope.getColumnAsArray(relation.ForeignKey))
|
||
|
|
case "many_to_many":
|
||
|
|
scope.Err(errors.New("not supported relation"))
|
||
|
|
default:
|
||
|
|
scope.Err(errors.New("not supported relation"))
|
||
|
|
}
|
||
|
|
break
|
||
|
|
}
|
||
|
|
}
|
||
|
|
}
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
func makeSlice(value reflect.Value) interface{} {
|
||
|
|
typ := value.Type()
|
||
|
|
if value.Kind() == reflect.Slice {
|
||
|
|
typ = typ.Elem()
|
||
|
|
}
|
||
|
|
sliceType := reflect.SliceOf(typ)
|
||
|
|
slice := reflect.New(sliceType)
|
||
|
|
slice.Elem().Set(reflect.MakeSlice(sliceType, 0, 0))
|
||
|
|
return slice.Interface()
|
||
|
|
}
|
||
|
|
|
||
|
|
func (scope *Scope) getColumnAsArray(column string) (primaryKeys []interface{}) {
|
||
|
|
values := scope.IndirectValue()
|
||
|
|
switch values.Kind() {
|
||
|
|
case reflect.Slice:
|
||
|
|
for i := 0; i < values.Len(); i++ {
|
||
|
|
value := values.Index(i)
|
||
|
|
primaryKeys = append(primaryKeys, value.FieldByName(column).Interface())
|
||
|
|
}
|
||
|
|
case reflect.Struct:
|
||
|
|
return []interface{}{values.FieldByName(column).Interface()}
|
||
|
|
}
|
||
|
|
return
|
||
|
|
}
|