Modify: Decide whether to redirect when previewing based on storage policy

models/migration.go

@@ -102,6 +102,7 @@ solid #e9e9e9;"bgcolor="#fff"><tbody><tr style="font-family: 'Helvetica Neue',He
 		{Name: "oss_timeout", Value: `3600`, Type: "timeout"},
 		{Name: "archive_timeout", Value: `30`, Type: "timeout"},
 		{Name: "download_timeout", Value: `30`, Type: "timeout"},
+		{Name: "preview_timeout", Value: `60`, Type: "timeout"},
 		{Name: "doc_preview_timeout", Value: `60`, Type: "timeout"},
 		{Name: "upload_credential_timeout", Value: `1800`, Type: "timeout"},
 		{Name: "upload_session_timeout", Value: `86400`, Type: "timeout"},

models/policy.go

@@ -67,6 +67,12 @@ func GetPolicyByID(ID interface{}) (Policy, error) {
 	return policy, result.Error
 }
 
+// IsDirectlyPreview 返回此策略下文件是否可以直接预览（不需要重定向）
+// TODO 测试
+func (policy *Policy) IsDirectlyPreview() bool {
+	return policy.Type == "local"
+}
+
 // AfterFind 找到存储策略后的钩子
 func (policy *Policy) AfterFind() (err error) {
 	// 解析存储策略设置到OptionsSerialized