migrate from github

internal/repository/document_repo/get_content.go

@@ -0,0 +1,41 @@
+package document_repo
+
+import (
+	"github.com/XingfenD/yoresee_doc/internal/model"
+	"gorm.io/gorm"
+)
+
+type DocumentGetContentOperation struct {
+	repo       *DocumentRepository
+	documentID int64
+	tx         *gorm.DB
+}
+
+func (r *DocumentRepository) GetContent(documentID int64) *DocumentGetContentOperation {
+	return &DocumentGetContentOperation{
+		repo:       r,
+		documentID: documentID,
+	}
+}
+
+func (op *DocumentGetContentOperation) WithTx(tx *gorm.DB) *DocumentGetContentOperation {
+	op.tx = tx
+	return op
+}
+
+func (op *DocumentGetContentOperation) Exec() (string, error) {
+	var docMeta model.Document
+	var err error
+
+	db := op.repo.db
+	if op.tx != nil {
+		db = op.tx
+	}
+
+	err = db.Where("id = ?", op.documentID).First(&docMeta).Error
+	if err != nil {
+		return "", err
+	}
+
+	return docMeta.Content, nil
+}