Remove deprecated headers/options and switched to C++20

.github/workflows/windows_mingw.yml

@@ -17,7 +17,6 @@ env:
   BUILD_TYPE: Release
   CLICKHOUSE_USER: clickhouse_cpp_cicd
   CLICKHOUSE_PASSWORD: clickhouse_cpp_cicd
-
   #
   # CLICKHOUSE_HOST: localhost
   # CLICKHOUSE_PORT: 9000

CMakeLists.txt

@@ -2,7 +2,7 @@ CMAKE_MINIMUM_REQUIRED (VERSION 3.5.2)
 
 LIST (APPEND CMAKE_MODULE_PATH "${CMAKE_CURRENT_SOURCE_DIR}/cmake")
 
-INCLUDE (cpp17)
+INCLUDE (cpp20)
 INCLUDE (subdirs)
 INCLUDE (openssl)
 INCLUDE (version)
@@ -22,7 +22,7 @@ PROJECT (CLICKHOUSE-CLIENT
     DESCRIPTION "ClickHouse C++ client library"
 )
 
-USE_CXX17 ()
+USE_CXX20 ()
 USE_OPENSSL ()
 
 IF (CLICKHOUSE_CPP_CHECK_VERSION)

clickhouse/CMakeLists.txt

@@ -45,8 +45,8 @@ SET ( clickhouse-cpp-lib-src
     base/singleton.h
     base/socket.h
     base/sslsocket.h
-    base/string_utils.h
-    base/string_view.h
+
+
     base/uuid.h
     base/wire_format.h
 
@@ -61,7 +61,7 @@ SET ( clickhouse-cpp-lib-src
     columns/ip6.h
     columns/itemview.h
     columns/lowcardinality.h
-    columns/lowcardinalityadaptor.h
+
     columns/map.h
     columns/nothing.h
     columns/nullable.h

clickhouse/client.cpp

@@ -605,9 +605,6 @@ bool Client::Impl::ReadBlock(InputStream& input, Block* block) {
         return false;
     }
 
-    CreateColumnByTypeSettings create_column_settings;
-    create_column_settings.low_cardinality_as_wrapped_column = options_.backward_compatibility_lowcardinality_as_wrapped_column;
-
     for (size_t i = 0; i < num_columns; ++i) {
         std::string name;
         std::string type;
@@ -618,7 +615,7 @@ bool Client::Impl::ReadBlock(InputStream& input, Block* block) {
             return false;
         }
 
-        if (ColumnRef col = CreateColumnByType(type, create_column_settings)) {
+        if (ColumnRef col = CreateColumnByType(type)) {
             if (num_rows && !col->Load(&input, num_rows)) {
                 throw ProtocolError("can't load column '" + name + "' of type " + type);
             }

clickhouse/client.h

@@ -117,15 +117,6 @@ struct ClientOptions {
     DECLARE_FIELD(connection_recv_timeout, std::chrono::milliseconds, SetConnectionRecvTimeout, std::chrono::milliseconds(0));
     DECLARE_FIELD(connection_send_timeout, std::chrono::milliseconds, SetConnectionSendTimeout, std::chrono::milliseconds(0));
 
-    /** It helps to ease migration of the old codebases, which can't afford to switch
-    * to using ColumnLowCardinalityT or ColumnLowCardinality directly,
-    * but still want to benefit from smaller on-wire LowCardinality bandwidth footprint.
-    *
-    * @see LowCardinalitySerializationAdaptor, CreateColumnByType
-    */
-    [[deprecated("Makes implementation of LC(X) harder and code uglier. Will be removed in next major release (3.0) ")]]
-    DECLARE_FIELD(backward_compatibility_lowcardinality_as_wrapped_column, bool, SetBakcwardCompatibilityFeatureLowCardinalityAsWrappedColumn, false);
-
     /** Set max size data to compress if compression enabled.
      *
      *  Allows choosing tradeoff between RAM\CPU:

clickhouse/columns/factory.cpp

@@ -8,7 +8,6 @@
 #include "ip4.h"
 #include "ip6.h"
 #include "lowcardinality.h"
-#include "lowcardinalityadaptor.h"
 #include "map.h"
 #include "nothing.h"
 #include "nullable.h"
@@ -132,17 +131,17 @@ static ColumnRef CreateTerminalColumn(const TypeAst& ast) {
     }
 }
 
-static ColumnRef CreateColumnFromAst(const TypeAst& ast, CreateColumnByTypeSettings settings) {
+static ColumnRef CreateColumnFromAst(const TypeAst& ast) {
     switch (ast.meta) {
         case TypeAst::Array: {
             return std::make_shared<ColumnArray>(
-                CreateColumnFromAst(GetASTChildElement(ast, 0), settings)
+                CreateColumnFromAst(GetASTChildElement(ast, 0))
             );
         }
 
         case TypeAst::Nullable: {
             return std::make_shared<ColumnNullable>(
-                CreateColumnFromAst(GetASTChildElement(ast, 0), settings),
+                CreateColumnFromAst(GetASTChildElement(ast, 0)),
                 std::make_shared<ColumnUInt8>()
             );
         }
@@ -156,7 +155,7 @@ static ColumnRef CreateColumnFromAst(const TypeAst& ast, CreateColumnByTypeSetti
 
             columns.reserve(ast.elements.size());
             for (const auto& elem : ast.elements) {
-                if (auto col = CreateColumnFromAst(elem, settings)) {
+                if (auto col = CreateColumnFromAst(elem)) {
                     columns.push_back(col);
                 } else {
                     return nullptr;
@@ -194,36 +193,20 @@ static ColumnRef CreateColumnFromAst(const TypeAst& ast, CreateColumnByTypeSetti
         }
         case TypeAst::LowCardinality: {
             const auto nested = GetASTChildElement(ast, 0);
-            if (settings.low_cardinality_as_wrapped_column) {
-                switch (nested.code) {
-                    // TODO (nemkov): update this to maximize code reuse.
-                    case Type::String:
-                        return std::make_shared<LowCardinalitySerializationAdaptor<ColumnString>>();
-                    case Type::FixedString:
-                        return std::make_shared<LowCardinalitySerializationAdaptor<ColumnFixedString>>(GetASTChildElement(nested, 0).value);
-                    case Type::Nullable:
-                        throw UnimplementedError("LowCardinality(" + nested.name + ") is not supported with LowCardinalityAsWrappedColumn on");
-                    default:
-                        throw UnimplementedError("LowCardinality(" + nested.name + ") is not supported");
-                }
-            }
-            else {
-                switch (nested.code) {
-                    // TODO (nemkov): update this to maximize code reuse.
-                    case Type::String:
-                        return std::make_shared<ColumnLowCardinalityT<ColumnString>>();
-                    case Type::FixedString:
-                        return std::make_shared<ColumnLowCardinalityT<ColumnFixedString>>(GetASTChildElement(nested, 0).value);
-                    case Type::Nullable:
-                        return std::make_shared<ColumnLowCardinality>(
-                            std::make_shared<ColumnNullable>(
-                                CreateColumnFromAst(GetASTChildElement(nested, 0), settings),
-                                std::make_shared<ColumnUInt8>()
-                            )
-                        );
-                    default:
-                        throw UnimplementedError("LowCardinality(" + nested.name + ") is not supported");
-                }
+            switch (nested.code) {
+                case Type::String:
+                    return std::make_shared<ColumnLowCardinalityT<ColumnString>>();
+                case Type::FixedString:
+                    return std::make_shared<ColumnLowCardinalityT<ColumnFixedString>>(GetASTChildElement(nested, 0).value);
+                case Type::Nullable:
+                    return std::make_shared<ColumnLowCardinality>(
+                        std::make_shared<ColumnNullable>(
+                            CreateColumnFromAst(GetASTChildElement(nested, 0)),
+                            std::make_shared<ColumnUInt8>()
+                        )
+                    );
+                default:
+                    throw UnimplementedError("LowCardinality(" + nested.name + ") is not supported");
             }
         }
         case TypeAst::SimpleAggregateFunction: {
@@ -239,7 +222,7 @@ static ColumnRef CreateColumnFromAst(const TypeAst& ast, CreateColumnByTypeSetti
 
             columns.reserve(ast.elements.size());
             for (const auto& elem : ast.elements) {
-                if (auto col = CreateColumnFromAst(elem, settings)) {
+                if (auto col = CreateColumnFromAst(elem)) {
                     columns.push_back(col);
                 } else {
                     return nullptr;
@@ -263,14 +246,12 @@ static ColumnRef CreateColumnFromAst(const TypeAst& ast, CreateColumnByTypeSetti
 
 } // namespace
 
-
-ColumnRef CreateColumnByType(const std::string& type_name, CreateColumnByTypeSettings settings) {
+ColumnRef CreateColumnByType(const std::string& type_name) {
     auto ast = ParseTypeName(type_name);
     if (ast != nullptr) {
-        return CreateColumnFromAst(*ast, settings);
+        return CreateColumnFromAst(*ast);
     }
 
     return nullptr;
 }
-
 }

clickhouse/columns/factory.h

@@ -4,11 +4,6 @@
 
 namespace clickhouse {
 
-struct CreateColumnByTypeSettings
-{
-    bool low_cardinality_as_wrapped_column = false;
-};
-
-ColumnRef CreateColumnByType(const std::string& type_name, CreateColumnByTypeSettings settings = {});
+ColumnRef CreateColumnByType(const std::string& type_name);
 
 }