How to reinitialise an embedded Python interpreter?

Question

I\'m working on embedding Python in our test suite application. The purpose is to use Python to run several tests scripts to collect data and make a report of tests. Multiple te

Answer 1

I'd write another shell script executing the sequence of test scripts with new instances of python each time. Or write it in python like

# run your tests in the process first
# now run the user scripts, each in new process to have virgin env
for script in userScript:
    subprocess.call(['python',script])

Answer 2

Here is another way I found to achieve what I want, start with a clean slate in the interpreter.

I can control the global and local namespaces I use to execute the code:

// get the dictionary from the main module
// Get pointer to main module of python script
object main_module = import("__main__");
// Get dictionary of main module (contains all variables and stuff)
object main_namespace = main_module.attr("__dict__");

// define the dictionaries to use in the interpreter
dict global_namespace;
dict local_namespace;

// add the builtins
global_namespace["__builtins__"] = main_namespace["__builtins__"];

I can then use use the namespaces for execution of code contained in pyCode:

exec( pyCode, global_namespace, lobaca_namespace );

I can clean the namespaces when I want to run a new instance of my test, by cleaning the dictionaries:

// empty the interpreters namespaces
global_namespace.clear();
local_namespace.clear();        

// Copy builtins to new global namespace
global_namespace["__builtins__"] = main_namespace["__builtins__"];

Depending at what level I want the execution, I can use global = local

Answer 3

How about using code.IteractiveInterpreter?

Something like this should do it:

#include <boost/python.hpp>
#include <string>
#include <stdexcept>

using namespace boost::python;

std::string GetPythonError()
{
    PyObject *ptype = NULL, *pvalue = NULL, *ptraceback = NULL;
    PyErr_Fetch(&ptype, &pvalue, &ptraceback);
    std::string message("");
    if(pvalue && PyString_Check(pvalue)) {
        message = PyString_AsString(pvalue);
    }
    return message;
}

// Must be called after Py_Initialize()
void RunInterpreter(std::string codeToRun)
{
    object pymodule = object(handle<>(borrowed(PyImport_AddModule("__main__"))));
    object pynamespace = pymodule.attr("__dict__");

    try {
        // Initialize the embedded interpreter
        object result = exec(   "import code\n"
                                "__myInterpreter = code.InteractiveConsole() \n", 
                                pynamespace);
        // Run the code
        str pyCode(codeToRun.c_str());
        pynamespace["__myCommand"] = pyCode;
        result = eval("__myInterpreter.push(__myCommand)", pynamespace);
    } catch(error_already_set) {
        throw std::runtime_error(GetPythonError().c_str());
    }
}