https://github.com/jbaldwin/libwingmysql
libwingmysql is a C++17 client library that provides and easy to use API for both synchronous and asynchrous MySQL queries.
libwingmysql is licensed under the Apache 2.0 license.
- Easy and safe to use C++17 client library API.
- Synchronous and Asynchronous MySQL query support.
- Socket pooling for re-using MySQL connections. Reduces reconnects.
- EventLoop background query thread for automatically handling inflight asynchronous queries.
- Background connect thread for new sockets -- doesn't block existing in flight queries.
- Completed async queries are notified to the user via simple callback.
See all of the examples under the examples/ directory.
#include <iostream>
#include <wing/WingMySQL.hpp>
int main(int argc, char* argv[])
{
using namespace std::chrono_literals;
if (argc < 7) {
std::cout << argv[0] << " <hostname> <port> <user> <password> <db> <query>\n";
return 1;
}
wing::GlobalScopeInitializer wing_gsi{};
// Create connection information to the mysql database.
wing::ConnectionInfo connection {
argv[1],
static_cast<uint16_t>(std::stoi(argv[2])),
argv[3],
argv[4],
argv[5],
0 };
// Create a statement, normally this would have wing::Statement::Arg()
// around parameters that should be bound, this is a simple example.
wing::Statement statement {};
statement << argv[6];
// Create an executor with the connection information and then start
// a query from the statement. This query is given a timeout of 30s.
// StartQuery() can fail, and thus returns std::optional, if this holds
// the std::future<wing::QueryHandle> then the query is executing, wait
// on the future to complete for the query results.
wing::Executor executor { std::move(connection) };
auto query_handle = executor.StartQuery(std::move(statement), 30s).value().get();
// If the query succeeded print the row contents, all columns can be viewed
// via AsStringView() but there are As<Type> functions to have wing convert
// the column value into the expected type for you.
if (query_handle->QueryStatus() == wing::QueryStatus::SUCCESS) {
std::cout << "Fields count: " << query_handle->FieldCount() << "\n";
std::cout << "Row count: " << query_handle->RowCount() << "\n";
for (const auto& row : query_handle->Rows()) {
for (const auto& column : row.Columns()) {
auto value = column.AsStringView();
if (value.has_value()) {
std::cout << "NULL ";
} else {
std::cout << value.value() << " ";
}
}
std::cout << "\n";
}
} else {
std::cout << "An error occurred: " << wing::to_string(query_handle->QueryStatus()) << "\n";
}
return 0;
}Wing statements easily support escaping parameters by wrapping them into a
wing::Statement::Arg. If the type passed in is dedeuced to need escaping then wing
will automatically mysql escape the statement argument.
std::string to_be_escaped = "ESCAPE_ME";
int64_t i_wont_be_escaped = 5;
using Arg = wing::Statement::Arg;
wing::Statement statement {};
statement << "SELECT column FROM DATABASE WHERE name like " << Arg(to_be_escaped) << " AND id = " << Arg(i_wont_be_escaped);C++17 compiler
g++-9
clang-9
CMake
make or ninja
pthreads
zlib-devel
mysqlclient-devel
Test on:
ubuntu:18.04
ubuntu:20.04
fedora:31
# This will produce a static library to link against your project.
mkdir Release && cd Release
cmake -DCMAKE_BUILD_TYPE=Release ..
cmake --build .
CMake options:
WING_BUILD_EXAMPLES "Build the examples. Default=ON"
WING_BUILD_TESTS "Build the tests. Default=ON"
WING_CODE_COVERAGE "Enable code coverage, tests must also be enabled. Default=OFF"
WING_MYSQL_OPT_SSL_ENFORCE_DISABLED "Disable MySQL option SSL enforce. Default=OFF"
WING_PERCONA_SSL_DISABLED "Disable Percona MySQL SSL. Default=OFF"
WING_LINK_LIBRARIES "User specified additinoal link targets for custom mysql libraries, defaults to system 'mysqlclient'."
To use within your cmake project you can clone the project or use git submodules and then add_subdirectory in the paren project's CMakeLists.txt, assuming the wing code is in a libwingmysql/ subdirectory of the parent project:
add_subdirectory(libwingmysql)
To link to the <project_name> then use the following:
add_executable(<project_name> main.cpp)
target_link_libraries(<project_name> PUBLIC wingmysql)
Include wing in the project's code by simply including #include <wing/WingMySQL.hpp> as needed.
CMake can also include the project directly via a FetchContent declaration. In your project's CMakeLists.txt
include the following code to download the git repository and make it available to link to.
cmake_minimum_required(VERSION 3.11)
# ... cmake project stuff ...
include(FetchContent)
FetchContent_Declare(
wingmysql
GIT_REPOSITORY https://github.com/jbaldwin/libwingmysql.git
GIT_TAG <TAG_OR_GIT_HASH>
)
FetchContent_MakeAvailable(wingmysql)
# ... cmake project more stuff ...
target_link_libraries(${PROJECT_NAME} PUBLIC wingmysql)
The tests are automatically run by GitHub Actions on all Pull Requests. They can also be ran locally with a default
localhost instance of mysql. To do so the CMake option WING_LOCALHOST_TESTS=ON must be set otherwise the tests will use the hostname mysql setup in the CI settings. After building and starting mysql tests can be run by issuing:
# Invoke via cmake:
ctest -v
# Or invoke directly to see error messages if tests are failing:
./test/libwingmysql_tests
...TODO...
File bug reports, feature requests and questions using GitHub Issues
Copyright © 2017-2020, Josh Baldwin