feat postgresql: allow using mapped enums in ParameterStore

Tests: протестировано CI
commit_hash:c67f1b9e57f0a5e5df54f542f870ea287411f7c9

Author: apolukhin

postgresql/include/userver/storages/postgres/parameter_store.hpp

@@ -32,12 +32,14 @@ class ParameterStore {
     ParameterStore& operator=(ParameterStore&&) = default;
 
     /// @brief Adds a parameter to the end of the parameter list.
-    /// @note Currently only built-in/system types are supported.
+    /// @note Currently only enums and built-in/system types are supported.
     template <typename T>
     ParameterStore& PushBack(const T& param) {
         static_assert(
-            io::IsTypeMappedToSystem<T>() || io::IsTypeMappedToSystemArray<T>(),
-            "Currently only built-in types can be used in ParameterStore"
+            io::IsTypeMappedToSystem<T>() || io::IsTypeMappedToSystemArray<T>() ||
+                (std::is_enum_v<T> && io::traits::kIsMappedToPg<T> &&
+                 std::is_same_v<typename io::CppToPg<T>::Mapping, io::CppToUserPg<typename io::CppToPg<T>::Type>>),
+            "Currently only built-in and enum types can be used in ParameterStore"
         );
         data_.Write(kNoUserTypes, param);
         return *this;

postgresql/src/storages/postgres/tests/enums_pgtest.cpp

@@ -79,6 +79,15 @@ struct storages::postgres::io::CppToUserPg<AnotherRainbow> : storages::postgres:
 };
 /*! [User enum type cpp2] */
 
+namespace pg_absrnd_mvp::transaction_type {
+
+enum class Enum : std::uint16_t { kPosting = 0, kHold = 1 };
+
+constexpr utils::StringLiteral kPosting{"posting"};
+constexpr utils::StringLiteral kHold{"hold"};
+
+}  // namespace pg_absrnd_mvp::transaction_type
+
 // Reopen the namespace not to get to the code snippet
 namespace storages::postgres::io {
 
@@ -107,6 +116,17 @@ struct CppToUserPg<AnotherRainbowRO> : EnumMappingBase<AnotherRainbowRO> {
     };
 };
 
+template <>
+struct CppToUserPg<pg_absrnd_mvp::transaction_type::Enum> : EnumMappingBase<pg_absrnd_mvp::transaction_type::Enum> {
+    static constexpr DBTypeName postgres_name = "__pgtest.transaction_type";
+    static constexpr USERVER_NAMESPACE::utils::TrivialBiMap enumerators = [](auto selector)
+    {
+        return selector()
+            .Case(pg_absrnd_mvp::transaction_type::kPosting, pg_absrnd_mvp::transaction_type::Enum::kPosting)
+            .Case(pg_absrnd_mvp::transaction_type::kHold, pg_absrnd_mvp::transaction_type::Enum::kHold);
+    };
+};
+
 namespace traits {
 
 // To ensure it is never written to a buffer
@@ -358,4 +378,38 @@ UTEST_P(PostgreConnection, AutogeneratedEnumToText) {
     UEXPECT_NO_THROW(GetConn()->Execute(kDropTestSchema)) << "Drop schema";
 }
 
+UTEST_P(PostgreConnection, EnumInParameterStore) {
+    CheckConnection(GetConn());
+    ASSERT_FALSE(GetConn()->IsReadOnly()) << "Expect a read-write connection";
+
+    UASSERT_NO_THROW(GetConn()->Execute(kDropTestSchema)) << "Drop schema";
+    UASSERT_NO_THROW(GetConn()->Execute(kCreateTestSchema)) << "Create schema";
+
+    // 'hold' and 'posting' order intentionally does not match C++ order/values
+    const std::string create_enum = "CREATE TYPE __pgtest.transaction_type AS enum ('hold', 'posting')";
+    UEXPECT_NO_THROW(GetConn()->Execute(create_enum)) << "Successfully created an enumeration type";
+    UEXPECT_NO_THROW(GetConn()->ReloadUserTypes()) << "Reload user types";
+
+    pg::ResultSet res{nullptr};
+    UEXPECT_NO_THROW(res = GetConn()->Execute("SELECT $1", pg_absrnd_mvp::transaction_type::Enum::kPosting));
+    EXPECT_EQ(pg_absrnd_mvp::transaction_type::Enum::kPosting, res[0][0].As<pg_absrnd_mvp::transaction_type::Enum>());
+
+    UEXPECT_NO_THROW(res = GetConn()->Execute("SELECT 'posting'::__pgtest.transaction_type"));
+
+    storages::postgres::ParameterStore parameter_store;
+    parameter_store.PushBack(pg_absrnd_mvp::transaction_type::Enum::kPosting);
+    parameter_store.PushBack(pg_absrnd_mvp::transaction_type::Enum::kHold);
+    UEXPECT_NO_THROW(res = GetConn()->Execute("SELECT $1, $2", parameter_store));
+    EXPECT_EQ(pg_absrnd_mvp::transaction_type::Enum::kPosting, res[0][0].As<pg_absrnd_mvp::transaction_type::Enum>());
+    EXPECT_EQ(pg_absrnd_mvp::transaction_type::Enum::kHold, res[0][1].As<pg_absrnd_mvp::transaction_type::Enum>());
+
+    const std::string create_table = "CREATE TABLE __pgtest.enum_table (i INTEGER, e __pgtest.transaction_type)";
+    UEXPECT_NO_THROW(GetConn()->Execute(create_table)) << "Successfully created a table";
+    UEXPECT_NO_THROW(GetConn()
+                         ->Execute("INSERT INTO __pgtest.enum_table(i, e) VALUES (1, $1), (2, $2)", parameter_store));
+    UEXPECT_NO_THROW(res = GetConn()->Execute("SELECT e FROM __pgtest.enum_table ORDER BY i"));
+    EXPECT_EQ(pg_absrnd_mvp::transaction_type::Enum::kPosting, res[0][0].As<pg_absrnd_mvp::transaction_type::Enum>());
+    EXPECT_EQ(pg_absrnd_mvp::transaction_type::Enum::kHold, res[1][0].As<pg_absrnd_mvp::transaction_type::Enum>());
+}
+
 USERVER_NAMESPACE_END