Filter a slice of struct based on a map with properties and values

gistfile1.go

package slicefilter

import "reflect"
import "fmt"

func Filter(src interface{}, filter map[string]interface{}, dst interface{}) error {
	srcRV := reflect.ValueOf(src)
	dstRV := reflect.ValueOf(dst)

	if srcRV.Kind() != reflect.Slice {
		return fmt.Errorf("set must be slice of struct, or slice of pointers of structs")
	}

	if dstRV.Kind() != reflect.Ptr {
		return fmt.Errorf("dst must be pointer to slice of struct, or slice of pointers of structs")
	}

	dstRV = dstRV.Elem()
	if dstRV.Kind() != reflect.Slice {
		return fmt.Errorf("dst must be pointer to slice of struct, or slice of pointers of structs")
	}

	for i := 0; i < srcRV.Len(); i++ {		
		rv := srcRV.Index(i)
		if rv.Kind() == reflect.Ptr {
			rv = rv.Elem()
		}

		if rv.Kind() != reflect.Struct {
			return fmt.Errorf("set must be a slice of structs or pointers to structs")
		}

		equal := true
		for prop, filterValue := range filter {
			field := rv.FieldByName(prop)

			// check if such field exists
			if field == reflect.ValueOf(nil) {
				equal = false
				break
			}

			// check if field and filter types are the same
			if field.Kind() != reflect.TypeOf(filterValue).Kind() {
				equal = false
				break
			}

			// check if values are the same
			if field.Interface() != filterValue {
				equal = false
				break
			}
		}

		if equal {
			dstRV.Set(reflect.Append(dstRV, rv))
		}
	}

	return nil
}

not foolproof, but good for a start.