Added more formal support for create table

CMakeLists.txt

@@ -103,14 +103,14 @@ if (PROJECT_IS_TOP_LEVEL)
         DESTINATION "${CMAKE_INSTALL_LIBDIR}/cmake/sqlgen"
     )
 
-    file(GLOB_RECURSE RFL_HEADERS RELATIVE ${CMAKE_CURRENT_LIST_DIR} "${CMAKE_CURRENT_LIST_DIR}/include/*" )
+    file(GLOB_RECURSE SQLGEN_HEADERS RELATIVE ${CMAKE_CURRENT_LIST_DIR} "${CMAKE_CURRENT_LIST_DIR}/include/*" )
 
     target_sources(sqlgen
         PUBLIC
         FILE_SET sqlgen_headers
         TYPE HEADERS
         BASE_DIRS $<BUILD_INTERFACE:${CMAKE_CURRENT_SOURCE_DIR}/include> $<BUILD_INTERFACE:${CMAKE_CURRENT_BINARY_DIR}/include>
-        FILES ${RFL_HEADERS})
+        FILES ${SQLGEN_HEADERS})
 
     install(
         TARGETS sqlgen

docs/README.md

@@ -14,6 +14,7 @@ Welcome to the sqlgen documentation. This guide provides detailed information ab
 
 - [sqlgen::read](reading.md) - How to read data from a database
 - [sqlgen::write](writing.md) - How to write data to a database
+- [sqlgen::create_table](create_table.md) - How to create a new table
 - [sqlgen::update](update.md) - How to update data in a table
 - [sqlgen::delete_from](delete_from.md) - How to delete data from a table
 - [sqlgen::drop](drop.md) - How to drop a table
@@ -30,4 +31,4 @@ Welcome to the sqlgen documentation. This guide provides detailed information ab
 - [PostgreSQL](postgres.md) - How to interact with PostgreSQL and compatible databases (Redshift, Aurora, Greenplum)
 - [SQLite](sqlite.md) - How to interact with SQLite3
 
-For installation instructions, quick start guide, and usage examples, please refer to the [main README](../README.md). 
+For installation instructions, quick start guide, and usage examples, please refer to the [main README](../README.md). 

docs/to_sql.md

@@ -91,7 +91,7 @@ struct TestTable {
 };
 
 // Create table query
-const auto create_query = sqlgen::CreateTable<TestTable>{};
+const auto create_query = create_table<TestTable> | if_not_exists;
 const auto sql = postgres::to_sql(create_query);
 ```
 

include/sqlgen.hpp

@@ -2,7 +2,6 @@
 #define SQLGEN_HPP_
 
 #include "sqlgen/Connection.hpp"
-#include "sqlgen/CreateTable.hpp"
 #include "sqlgen/Flatten.hpp"
 #include "sqlgen/Insert.hpp"
 #include "sqlgen/Iterator.hpp"
@@ -18,9 +17,11 @@
 #include "sqlgen/begin_transaction.hpp"
 #include "sqlgen/col.hpp"
 #include "sqlgen/commit.hpp"
+#include "sqlgen/create_table.hpp"
 #include "sqlgen/delete_from.hpp"
 #include "sqlgen/drop.hpp"
 #include "sqlgen/if_exists.hpp"
+#include "sqlgen/if_not_exists.hpp"
 #include "sqlgen/limit.hpp"
 #include "sqlgen/order_by.hpp"
 #include "sqlgen/patterns.hpp"

include/sqlgen/CreateTable.hpp

@@ -1,15 +0,0 @@
-#ifndef SQLGEN_CREATETABLE_HPP_
-#define SQLGEN_CREATETABLE_HPP_
-
-#include <rfl.hpp>
-
-namespace sqlgen {
-
-/// Helper class for to_sql.
-template <class T>
-struct CreateTable {};
-
-};  // namespace sqlgen
-
-#endif
-

include/sqlgen/create_table.hpp

@@ -0,0 +1,46 @@
+#ifndef SQLGEN_CREATETABLE_HPP_
+#define SQLGEN_CREATETABLE_HPP_
+
+#include <rfl.hpp>
+
+#include "transpilation/to_create_table.hpp"
+
+namespace sqlgen {
+
+template <class ValueType>
+Result<Ref<Connection>> create_table_impl(const Ref<Connection>& _conn,
+                                          const bool _if_not_exists) {
+  const auto query = transpilation::to_create_table<ValueType>(_if_not_exists);
+  return _conn->execute(_conn->to_sql(query)).transform([&](const auto&) {
+    return _conn;
+  });
+}
+
+template <class ValueType>
+Result<Ref<Connection>> create_table_impl(const Result<Ref<Connection>>& _res,
+                                          const bool _if_not_exists) {
+  return _res.and_then([&](const auto& _conn) {
+    return create_table_impl<ValueType>(_conn, _if_not_exists);
+  });
+}
+
+template <class ValueType>
+struct CreateTable {
+  Result<Ref<Connection>> operator()(const auto& _conn) const noexcept {
+    try {
+      return create_table_impl<ValueType>(_conn, if_not_exists_);
+    } catch (std::exception& e) {
+      return error(e.what());
+    }
+  }
+
+  bool if_not_exists_;
+};
+
+template <class ContainerType>
+const auto create_table = CreateTable<ContainerType>{};
+
+};  // namespace sqlgen
+
+#endif
+

include/sqlgen/if_not_exists.hpp

@@ -0,0 +1,19 @@
+#ifndef SQLGEN_IF_NOT_EXISTS_HPP_
+#define SQLGEN_IF_NOT_EXISTS_HPP_
+
+namespace sqlgen {
+
+struct IfNotExists {};
+
+template <class OtherType>
+auto operator|(const OtherType& _o, const IfNotExists&) {
+  auto o = _o;
+  o.if_not_exists_ = true;
+  return o;
+}
+
+inline const auto if_not_exists = IfNotExists{};
+
+}  // namespace sqlgen
+
+#endif

include/sqlgen/transpilation/to_create_table.hpp

@@ -18,7 +18,7 @@ namespace sqlgen::transpilation {
 template <class T>
   requires std::is_class_v<std::remove_cvref_t<T>> &&
            std::is_aggregate_v<std::remove_cvref_t<T>>
-dynamic::CreateTable to_create_table() {
+dynamic::CreateTable to_create_table(const bool _if_not_exists = true) {
   using NamedTupleType = rfl::named_tuple_t<std::remove_cvref_t<T>>;
   using Fields = typename NamedTupleType::Fields;
   return dynamic::CreateTable{
@@ -26,7 +26,7 @@ dynamic::CreateTable to_create_table() {
           dynamic::Table{.name = get_tablename<T>(), .schema = get_schema<T>()},
       .columns = make_columns<Fields>(
           std::make_integer_sequence<int, rfl::tuple_size_v<Fields>>()),
-      .if_not_exists = true};
+      .if_not_exists = _if_not_exists};
 }
 
 }  // namespace sqlgen::transpilation

include/sqlgen/transpilation/to_sql.hpp

@@ -3,8 +3,8 @@
 
 #include <vector>
 
-#include "../CreateTable.hpp"
 #include "../Insert.hpp"
+#include "../create_table.hpp"
 #include "../delete_from.hpp"
 #include "../drop.hpp"
 #include "../dynamic/Statement.hpp"

sqlgen-config.cmake.in

@@ -1,5 +1,6 @@
 @PACKAGE_INIT@
 
+set(SQLGEN_POSTGRES @SQLGEN_POSTGRES@)
 set(SQLGEN_SQLITE3 @SQLGEN_SQLITE3@)
 
 include(CMakeFindDependencyMacro)
@@ -8,8 +9,12 @@ include(${CMAKE_CURRENT_LIST_DIR}/sqlgen-exports.cmake)
 
 find_dependency(reflectcpp)
 
+if(SQLGEN_POSTGRES)
+    find_dependency(PostgreSQL)
+endif()
+
 if(SQLGEN_SQLITE3)
-    find_dependency(sqlite3)
+    find_dependency(unofficial-sqlite3)
 endif()
 
 check_required_components(sqlgen)

tests/sqlite/test_create_table.cpp

@@ -0,0 +1,30 @@
+#include <gtest/gtest.h>
+
+#include <rfl.hpp>
+#include <rfl/json.hpp>
+#include <sqlgen.hpp>
+#include <sqlgen/sqlite.hpp>
+#include <vector>
+
+namespace test_create_table {
+
+struct Person {
+  sqlgen::PrimaryKey<uint32_t> id;
+  std::string first_name;
+  std::string last_name;
+  int age;
+};
+
+TEST(sqlite, test_create_table) {
+  using namespace sqlgen;
+
+  const auto people = sqlgen::sqlite::connect()
+                          .and_then(create_table<Person> | if_not_exists)
+                          .and_then(sqlgen::read<std::vector<Person>>);
+
+  const std::string expected = R"([])";
+
+  EXPECT_EQ(rfl::json::write(people), expected);
+}
+
+}  // namespace test_create_table