From e6b6888b90f730518e5fe3aa132a628d88f5ea50 Mon Sep 17 00:00:00 2001
From: ZhuchkaTriplesix <mrlololoshka94@gmail.com>
Date: Mon, 28 Sep 2026 17:09:57 +0300
Subject: [PATCH] fix(schema): fix format mismatch in getObjectMetadata and
 getServerStats scalar queries

handle_get_server_stats and handle_get_object_metadata requested
SELECT version(), SELECT uptime() and SHOW CREATE TABLE with FORMAT
JSONCompactEachRow (a single data line, no headers), then parsed the
response with parse_compact_output, which unconditionally expects
FORMAT JSONCompactEachRowWithNamesAndTypes (names line + types line +
data lines). Against a real ClickHouse server this always failed to
parse, silently falling back to "ClickHouse"/0/"" defaults.

Switch all three queries to FORMAT JSONCompactEachRowWithNamesAndTypes
so parse_compact_output can read them, and update the version/uptime
network-error fallbacks to the same shape. Closes #57
---
 src/mapper/row_compact.rs  | 22 ++++++++++++++++++++++
 src/rpc/handlers/schema.rs | 26 +++++++++++++++++++++-----
 2 files changed, 43 insertions(+), 5 deletions(-)

diff --git a/src/mapper/row_compact.rs b/src/mapper/row_compact.rs
index 99012c0..64440ee 100644
--- a/src/mapper/row_compact.rs
+++ b/src/mapper/row_compact.rs
@@ -159,6 +159,28 @@ mod tests {
         assert_eq!(res.statistics.elapsed_ms, 15);
     }
 
+    #[test]
+    fn test_parse_compact_output_scalar_row() {
+        // Regression for issue #57: scalar introspection queries
+        // (SELECT version(), SELECT uptime(), SHOW CREATE TABLE) must be
+        // requested with FORMAT JSONCompactEachRowWithNamesAndTypes so this
+        // parser's fixed 2-header-line assumption holds; a bare
+        // JSONCompactEachRow response has no names/types lines and would
+        // previously fail with "missing names or types row".
+        let version_output = r#"["version()"]
+["String"]
+["24.3.1.2452"]"#;
+        let res = parse_compact_output(version_output, 0).unwrap();
+        assert_eq!(res.rows.len(), 1);
+        assert_eq!(res.rows[0][0], json!("24.3.1.2452"));
+
+        let uptime_output = r#"["uptime()"]
+["UInt32"]
+[123456]"#;
+        let res = parse_compact_output(uptime_output, 0).unwrap();
+        assert_eq!(res.rows[0][0].as_u64(), Some(123456));
+    }
+
     #[test]
     fn test_parse_compact_output_empty() {
         let res = parse_compact_output("", 5).unwrap();
diff --git a/src/rpc/handlers/schema.rs b/src/rpc/handlers/schema.rs
index 9ad3c19..51036b8 100644
--- a/src/rpc/handlers/schema.rs
+++ b/src/rpc/handlers/schema.rs
@@ -322,13 +322,29 @@ pub async fn handle_get_server_stats(params: Option<Value>) -> Result<Value, Dri
     }
 
     let version_text = client
-        .post_sql("SELECT version() FORMAT JSONCompactEachRow", |_| {})
+        .post_sql(
+            "SELECT version() FORMAT JSONCompactEachRowWithNamesAndTypes",
+            |_| {},
+        )
         .await
-        .unwrap_or_else(|_| r#"["ClickHouse unknown"]"#.to_string());
+        .unwrap_or_else(|_| {
+            r#"["version()"]
+["String"]
+["unknown"]"#
+                .to_string()
+        });
     let uptime_text = client
-        .post_sql("SELECT uptime() FORMAT JSONCompactEachRow", |_| {})
+        .post_sql(
+            "SELECT uptime() FORMAT JSONCompactEachRowWithNamesAndTypes",
+            |_| {},
+        )
         .await
-        .unwrap_or_else(|_| r#"[0]"#.to_string());
+        .unwrap_or_else(|_| {
+            r#"["uptime()"]
+["UInt32"]
+[0]"#
+                .to_string()
+        });
 
     let mut version_str = "ClickHouse".to_string();
     if let Ok(parsed) = crate::mapper::row_compact::parse_compact_output(&version_text, 0)
@@ -421,7 +437,7 @@ pub async fn handle_get_object_metadata(params: Option<Value>) -> Result<Value,
     }
 
     let ddl_sql = format!(
-        "SHOW CREATE TABLE {}.{} FORMAT JSONCompactEachRow",
+        "SHOW CREATE TABLE {}.{} FORMAT JSONCompactEachRowWithNamesAndTypes",
         crate::utils::sql_escape::quote_identifier(db_name),
         crate::utils::sql_escape::quote_identifier(tbl_name)
     );