数据集不能创建多个

models/dataset.go

@@ -101,11 +101,28 @@ type SearchDatasetOptions struct {
 }
 
 func CreateDataset(dataset *Dataset) (err error) {
-	if _, err = x.Insert(dataset); err != nil {
+
+	sess := x.NewSession()
+	defer sess.Close()
+
+	if err := sess.Begin(); err != nil {
 		return err
 	}
 
-	return nil
+	datasetByRepoId := &Dataset{RepoID: dataset.RepoID}
+	has, err := sess.Get(datasetByRepoId)
+	if err != nil {
+		return err
+	}
+	if has {
+		return fmt.Errorf("The dataset already exists.")
+	}
+
+	if _, err = sess.Insert(dataset); err != nil {
+		return err
+	}
+	return sess.Commit()
+
 }
 
 func SearchDataset(opts *SearchDatasetOptions) (DatasetList, int64, error) {