smpests / python-online Goto Github PK

A simple wrapper for python interpreter, and relevant implementation for building web socket service. The highlight is that We built a language bridge for Java and Python Using C++ API.

pythonutil is a simple wrapper for python interpreter using C API provided by Python3. (So the current pythonutil is only for Python3)

In pythonutil, we try to redirect python's stdout/stderr into C level stdio. The solution is found on Python sys.stdout redirection in C++. The relevant StackOverflow question is How To catch python stdout in c++ code

Because of future extension, we use the C++ solution instead of the simple python solution. In this solution, we could register callback functions for stdout and stderr.

service is a java web application based on the SpringMVC framework. Additional, we deploy an optional database for user data persistence based on hibernate. We built a simple combination for SpringMVC and hibernate.

It is just a common user module for authentication.

Python Service is the most important module for multi-user python interpreter online. We define ProcessStreamRunnable to process single user interpreter requests. The Runnables are submitted to a CachedThreadPool.

Moreover, AsyncInputReader and AsyncOutputWriter are built for pythonutil IO. The former accepts an InputStream and a StreamDelegate as parameters, if the InputStream is not null, the reader would invoke the delegate and pass the data to delegate target. The later accepts an InputStream and a PipedOutputStream as parameters, if the PipedOutputStream is accessible, it would write the piped data to the InputStream. The reader and writer work in independent polling thread.

There are some properties for web application.

1. hibernate.properties: url/username/password for mysql in jdbc
2. python-config: path for pythonutil

As mentioned above, we use three threads to support one online interpreter, the AsyncReader may not be efficient to catch output stream from pythonutil. In fact, we found that the buffer length is sensitive to both C++ to Java and Java to Web processes.

pythonutil is running at the host server currently, it could be harmful to server if some bad code is submitted. We could deploy sandbox for pythonutil for future uses.