ApplicationsLib Namespace Reference

Namespaces
namespace	anonymous_namespace{ogs_embedded_python.cpp}
namespace	detail

Classes
struct	LinearSolverLibrarySetup
class	TestDefinition

Functions
pybind11::scoped_interpreter	setupEmbeddedPython ()
void	setupEmbeddedPythonVenvPaths ()

Function Documentation

setupEmbeddedPython()

OGS_EXPORT_SYMBOL pybind11::scoped_interpreter ApplicationsLib::setupEmbeddedPython

(

)

Sets up an embedded Python interpreter and makes sure that the OpenGeoSys Python module is not removed by the linker.

Definition at line 35 of file ogs_embedded_python.cpp.

{
    // Allows ogs to be interrupted by SIGINT, which otherwise is handled by
    // python. See
    // https://docs.python.org/3/c-api/exceptions.html#c.PyErr_CheckSignals and
    // https://pybind11.readthedocs.io/en/stable/faq.html#how-can-i-properly-handle-ctrl-c-in-long-running-functions
    constexpr bool init_signal_handlers = false;
    return pybind11::scoped_interpreter{init_signal_handlers};
}

Referenced by main().

setupEmbeddedPythonVenvPaths()

OGS_EXPORT_SYMBOL void ApplicationsLib::setupEmbeddedPythonVenvPaths

(

)

Checks for activated and matching virtual environment and adds it to sys.path.

Definition at line 236 of file ogs_embedded_python.cpp.

{
    namespace py = pybind11;
    namespace fs = std::filesystem;
 
    // Get embedded Python version
    py::object const version_info =
        py::module_::import("sys").attr("version_info");
    int const emb_major = version_info.attr("major").cast<int>();
    int const emb_minor = version_info.attr("minor").cast<int>();
 
    // Check for virtual environment
    char const* const venv = std::getenv("VIRTUAL_ENV");
    if (venv == nullptr)
    {
        DBUG("No virtual environment detected (VIRTUAL_ENV not set).");
        return;
    }
 
    fs::path const venv_path(venv);
    DBUG("Virtual environment detected at: {}", venv_path.string());
 
    // Find and validate site-packages path for the embedded interpreter
    // version.
    fs::path const site_packages =
        findSitePackagesPath(venv_path, emb_major, emb_minor);
    INFO("Using virtual environment site-packages: {}", site_packages.string());
 
    // Add to sys.path via site.addsitedir() and not via a plain
    // sys.path.insert(): only the former processes the .pth files of the
    // directory. Ephemeral virtual environments created by `uv run --with ...`
    // contain no packages at all, but merely a .pth file chaining to the
    // directories the packages really live in. Without .pth processing not a
    // single package of such an environment would be importable.
    auto const sys = py::module_::import("sys");
    py::list const sys_path = sys.attr("path");
    std::size_t const num_paths_before = py::len(sys_path);
 
    py::module_::import("site").attr("addsitedir")(
        py::str(site_packages.string()));
 
    // addsitedir() appends, but the virtual environment's packages shall take
    // precedence over those of the embedded interpreter. Hence move the newly
    // added paths to the front, keeping their relative order.
    std::size_t const num_paths_after = py::len(sys_path);
    py::list reordered_path;
    for (std::size_t i = num_paths_before; i < num_paths_after; ++i)
    {
        reordered_path.append(sys_path[i]);
    }
    for (std::size_t i = 0; i < num_paths_before; ++i)
    {
        reordered_path.append(sys_path[i]);
    }
    sys.attr("path") = reordered_path;
}

References DBUG(), and INFO().

Referenced by main().