add postgres hstore type support

main_test.go

@@ -145,6 +145,11 @@ type Animal struct {
 	UpdatedAt time.Time
 }
 
+type Details struct {
+	Id   int64
+	Bulk gorm.Hstore
+}
+
 var (
 	db                 gorm.DB
 	t1, t2, t3, t4, t5 time.Time
@@ -2037,3 +2042,44 @@ func TestIndices(t *testing.T) {
 		t.Errorf("Got error when tried to create index: %+v", err)
 	}
 }
+
+func TestHstore(t *testing.T) {
+	if dialect := os.Getenv("GORM_DIALECT"); dialect != "postgres" {
+		t.Skip()
+	}
+
+	if err := db.Exec("CREATE EXTENSION IF NOT EXISTS hstore").Error; err != nil {
+		panic(fmt.Sprintf("No error should happen when create hstore extension, but got %+v", err))
+	}
+
+	db.Exec("drop table details")
+
+	if err := db.CreateTable(&Details{}).Error; err != nil {
+		panic(fmt.Sprintf("No error should happen when create table, but got %+v", err))
+	}
+
+	bankAccountId, phoneNumber, opinion := "123456", "14151321232", "sharkbait"
+	bulk := map[string]*string{
+		"bankAccountId": &bankAccountId,
+		"phoneNumber":   &phoneNumber,
+		"opinion":       &opinion,
+	}
+	d := Details{Bulk: bulk}
+	db.Save(&d)
+
+	var d2 Details
+	if err := db.First(&d2).Error; err != nil {
+		t.Errorf("Got error when tried to fetch details: %+v", err)
+	}
+
+	for k := range bulk {
+		r, ok := d2.Bulk[k]
+		if !ok {
+			t.Errorf("Details should be existed")
+		}
+		if res, _ := bulk[k]; *res != *r {
+			t.Errorf("Details should be equal")
+		}
+	}
+
+}

postgres.go

@@ -1,8 +1,12 @@
 package gorm
 
 import (
+	"database/sql"
+	"database/sql/driver"
 	"fmt"
 	"reflect"
+
+	"github.com/lib/pq/hstore"
 )
 
 type postgres struct {
@@ -35,6 +39,10 @@ func (d *postgres) SqlTag(value reflect.Value, size int) string {
 		if value.Type() == timeType {
 			return "timestamp with time zone"
 		}
+	case reflect.Map:
+		if value.Type() == hstoreType {
+			return "hstore"
+		}
 	default:
 		if _, ok := value.Interface().([]byte); ok {
 			return "bytea"
@@ -80,3 +88,43 @@ func (s *postgres) HasColumn(scope *Scope, tableName string, columnName string)
 	newScope.DB().QueryRow(newScope.Sql, newScope.SqlVars...).Scan(&count)
 	return count > 0
 }
+
+var hstoreType = reflect.TypeOf(Hstore{})
+
+type Hstore map[string]*string
+
+func (h Hstore) Value() (driver.Value, error) {
+	hstore := hstore.Hstore{Map: map[string]sql.NullString{}}
+	if len(h) == 0 {
+		return nil, nil
+	}
+
+	for key, value := range h {
+		hstore.Map[key] = sql.NullString{*value, true}
+	}
+	return hstore.Value()
+}
+
+func (h *Hstore) Scan(value interface{}) error {
+	hstore := hstore.Hstore{}
+
+	if err := hstore.Scan(value); err != nil {
+		return err
+	}
+
+	if len(hstore.Map) == 0 {
+		return nil
+	}
+
+	*h = Hstore{}
+	for k := range hstore.Map {
+		if hstore.Map[k].Valid {
+			s := hstore.Map[k].String
+			(*h)[k] = &s
+		} else {
+			(*h)[k] = nil
+		}
+	}
+
+	return nil
+}