YT-16386: Return original type of type_v1 columns in web_json

* Changelog entry
Type: feature
Component: proxy

Preserve original column types (e.g., `timestamp`) in `web_json` format of `select_rows` responses.
commit_hash:9e8bfa1fdc15eba92b2e105635446d49d57a1358

2 files changed, 9 insertions, 1 deletions

diff --git a/yt/yt/client/api/client_common.h b/yt/yt/client/api/client_common.h
index 58629a3167..6c88559134 100644
--- a/yt/yt/client/api/client_common.h
+++ b/yt/yt/client/api/client_common.h
@@ -192,6 +192,9 @@ struct TSelectRowsOptions
     bool UseCanonicalNullRelations = false;
     //! Merge versioned rows from different stores when reading.
     bool MergeVersionedRows = true;
+    //! For internal use only.
+    //! Use original table schema in result rowset.
+    bool UseOriginalTableSchema = false;
 };
 
 struct TFallbackReplicaOptions
diff --git a/yt/yt/client/driver/table_commands.cpp b/yt/yt/client/driver/table_commands.cpp
index 3cef7004d1..ce1155abfd 100644
--- a/yt/yt/client/driver/table_commands.cpp
+++ b/yt/yt/client/driver/table_commands.cpp
@@ -882,6 +882,12 @@ void TSelectRowsCommand::DoExecute(ICommandContextPtr context)
             Options.Timestamp);
     }
 
+    auto format = context->GetOutputFormat();
+    // Allows to display simple types like `timestamp` correctly in UI (YT-16386).
+    if (format.GetType() == EFormatType::WebJson) {
+        Options.UseOriginalTableSchema = true;
+    }
+
     auto result = WaitFor(clientBase->SelectRows(Query, Options))
         .ValueOrThrow();
 
@@ -896,7 +902,6 @@ void TSelectRowsCommand::DoExecute(ICommandContextPtr context)
         });
     }
 
-    auto format = context->GetOutputFormat();
     auto output = context->Request().OutputStream;
     auto writer = CreateSchemafulWriterForFormat(format, rowset->GetSchema(), output);