YQL-16444: fix empty prefix for yt batch list in io discovery

3 files changed, 15 insertions, 1 deletions

diff --git a/ydb/library/yql/providers/yt/gateway/native/yql_yt_native.cpp b/ydb/library/yql/providers/yt/gateway/native/yql_yt_native.cpp
index 7b7870f789..eb0d37b61c 100644
--- a/ydb/library/yql/providers/yt/gateway/native/yql_yt_native.cpp
+++ b/ydb/library/yql/providers/yt/gateway/native/yql_yt_native.cpp
@@ -487,7 +487,13 @@ public:
             auto resolvedLinksFuture = getFolderFuture.Apply([options, this, session] (const TFuture<TBatchFolderResult>& f) {
                 TVector<IYtGateway::TResolveOptions::TItemWithReqAttrs> resolveItems;
                 auto res = f.GetValue();
+                if (res.Items.empty()) {
+                    YQL_CLOG(INFO, ProviderYt) << "Skipping resolve for empty batch folder result";
+                    return res;
+                }
+
                 for (auto&& item : res.Items) {
+                    YQL_CLOG(DEBUG, ProviderYt) << "Adding to batch get command: " << item.Path;
                     IYtGateway::TResolveOptions::TItemWithReqAttrs resolveItem {
                         .Item = item,
                         .AttrKeys = options.Attributes()
@@ -512,6 +518,8 @@ public:
                 res.SetSuccess();
 
                 auto resolveRes = f.GetValue();
+                YQL_CLOG(INFO, ProviderYt) << "Batch get command got: " << resolveRes.Items.size() << " items";
+
                 TVector<TFolderResult::TFolderItem> items;
                 for (auto& batchItem : resolveRes.Items) {
                     TFolderResult::TFolderItem item {
diff --git a/ydb/library/yql/providers/yt/gateway/native/yql_yt_native_folders.cpp b/ydb/library/yql/providers/yt/gateway/native/yql_yt_native_folders.cpp
index f668633115..1fdc86f8ef 100644
--- a/ydb/library/yql/providers/yt/gateway/native/yql_yt_native_folders.cpp
+++ b/ydb/library/yql/providers/yt/gateway/native/yql_yt_native_folders.cpp
@@ -166,6 +166,7 @@ IYtGateway::TBatchFolderResult ExecGetFolder(const TExecContext<IYtGateway::TBat
     folderResult.SetSuccess();
 
     for (const auto& folder : execCtx->Options_.Folders()) {
+        YQL_CLOG(INFO, ProviderYt) << "Executing list command with prefix: " << folder.Prefix;
         const auto cacheKey = std::accumulate(folder.AttrKeys.begin(), folder.AttrKeys.end(), folder.Prefix,
             [] (TString&& str, const TString& arg) {
             return str + "&" + arg;
@@ -188,7 +189,10 @@ IYtGateway::TBatchFolderResult ExecGetFolder(const TExecContext<IYtGateway::TBat
                     folderItems.reserve(nodeList.size());
                     for (const auto& node : nodeList) {
                         TStringBuilder path;
-                        path << folder.Prefix << "/" << node.AsString();
+                        if (!folder.Prefix.Empty()) {
+                            path << folder.Prefix << "/";
+                        }
+                        path << node.AsString();
                         folderItems.push_back(MakeFolderItem(node, path));
                     }
                     StoreResInCache(entry, std::move(folderItems), cacheKey);
diff --git a/ydb/library/yql/providers/yt/provider/yql_yt_io_discovery.cpp b/ydb/library/yql/providers/yt/provider/yql_yt_io_discovery.cpp
index 08ce8f059e..a8d5625cfa 100644
--- a/ydb/library/yql/providers/yt/provider/yql_yt_io_discovery.cpp
+++ b/ydb/library/yql/providers/yt/provider/yql_yt_io_discovery.cpp
@@ -16,6 +16,7 @@
 #include <ydb/library/yql/core/peephole_opt/yql_opt_peephole_physical.h>
 #include <ydb/library/yql/core/issue/protos/issue_id.pb.h>
 #include <ydb/library/yql/core/issue/yql_issue.h>
+#include <ydb/library/yql/utils/log/log.h>
 
 #include <library/cpp/yson/node/node_io.h>
 #include <library/cpp/threading/future/future.h>
@@ -411,6 +412,7 @@ public:
                 }
 
                 auto items = std::get<TVector<IYtGateway::TFolderResult::TFolderItem>>(res->ItemsOrFileLink);
+                YQL_CLOG(INFO, ProviderYt) << "Got " << items.size() << " items for " << " GetFolder";
                 TVector<TExprBase> listItems;
                 for (auto& item: items) {
                     listItems.push_back(BuildFolderListItemExpr(ctx, node->Pos(), item));