From 988bf3a34e21891a888cf3e2d37429ced580ce4d Mon Sep 17 00:00:00 2001
From: Daniil Demin <deminds@ydb.tech>
Date: Fri, 9 Feb 2024 15:24:40 +0000
Subject: [PATCH] Use the same empty parsing context for early validation of
 view queries in CREATE VIEW statement and for selecting from the views

Preliminary validation is done by adding "query_ast" node to the
builded AST of the CREATE VIEW statement. It does not surve any real
purpose (it is not persisted in the scheme) as of now except early validation of view queries.
---
 ydb/core/kqp/ut/view/view_ut.cpp           | 18 +++++++++
 ydb/library/yql/sql/v1/sql_translation.cpp | 43 ++++++++++++++++------
 2 files changed, 49 insertions(+), 12 deletions(-)

diff --git a/ydb/core/kqp/ut/view/view_ut.cpp b/ydb/core/kqp/ut/view/view_ut.cpp
index c3eb3bd492dc..381dea85c6d9 100644
--- a/ydb/core/kqp/ut/view/view_ut.cpp
+++ b/ydb/core/kqp/ut/view/view_ut.cpp
@@ -324,6 +324,24 @@ Y_UNIT_TEST_SUITE(TCreateAndDropViewTest) {
             UNIT_ASSERT(dropResult.GetIssues().ToString().Contains("Error: Path does not exist"));
         }
     }
+
+    Y_UNIT_TEST(ContextPollution) {
+        TKikimrRunner kikimr(TKikimrSettings().SetWithSampleTables(false));
+        EnableViewsFeatureFlag(kikimr);
+        auto session = kikimr.GetTableClient().CreateSession().GetValueSync().GetSession();
+
+        ExecuteDataDefinitionQuery(session, R"(
+            CREATE VIEW InnerView WITH (security_invoker = TRUE) AS SELECT 1;
+        )");
+        ExecuteDataDefinitionQuery(session, R"(
+            CREATE VIEW OuterView WITH (security_invoker = TRUE) AS SELECT * FROM InnerView;
+        )");
+        
+        ExecuteDataDefinitionQuery(session, R"(
+            DROP VIEW OuterView;
+            CREATE VIEW OuterView WITH (security_invoker = TRUE) AS SELECT * FROM InnerView;
+        )");
+    }
 }
 
 Y_UNIT_TEST_SUITE(TSelectFromViewTest) {
diff --git a/ydb/library/yql/sql/v1/sql_translation.cpp b/ydb/library/yql/sql/v1/sql_translation.cpp
index 5b8a71852540..55375971f156 100644
--- a/ydb/library/yql/sql/v1/sql_translation.cpp
+++ b/ydb/library/yql/sql/v1/sql_translation.cpp
@@ -53,6 +53,33 @@ TString CollectTokens(const TRule_select_stmt& selectStatement) {
     return tokenCollector.Tokens;
 }
 
+NSQLTranslation::TTranslationSettings CreateViewTranslationSettings(const NSQLTranslation::TTranslationSettings& base) {
+    NSQLTranslation::TTranslationSettings settings;
+    
+    settings.ClusterMapping = base.ClusterMapping;
+    settings.Mode = NSQLTranslation::ESqlMode::LIMITED_VIEW;
+
+    return settings;
+}
+
+TNodePtr BuildViewSelect(const TRule_select_stmt& query, TContext& ctx) {
+    const auto viewTranslationSettings = CreateViewTranslationSettings(ctx.Settings);
+    TContext viewParsingContext(viewTranslationSettings, {}, ctx.Issues);
+    TSqlSelect select(viewParsingContext, viewTranslationSettings.Mode);
+    TPosition pos;
+    auto source = select.Build(query, pos);
+    if (!source) {
+        return nullptr;
+    }
+    return BuildSelectResult(
+        pos,
+        std::move(source),
+        false,
+        false,
+        viewParsingContext.Scoped
+    );
+}
+
 }
 
 namespace NSQLTranslationV1 {
@@ -4493,19 +4520,11 @@ bool TSqlTranslation::ParseViewQuery(std::map<TString, TDeferredAtom>& features,
     const TString queryText = CollectTokens(query);
     features["query_text"] = {Ctx.Pos(), queryText};
 
-    {
-        TSqlSelect select(Ctx, Mode);
-        TPosition pos;
-        auto source = select.Build(query, pos);
-        if (!source) {
-            return false;
-        }
-        features["query_ast"] = {BuildSelectResult(pos,
-                                                   std::move(source),
-                                                   false,
-                                                   false,
-                                                   Ctx.Scoped), Ctx};
+    const auto viewSelect = BuildViewSelect(query, Ctx);
+    if (!viewSelect) {
+        return false;
     }
+    features["query_ast"] = {viewSelect, Ctx};
 
     return true;
 }