ENH/TMP: Preliminary support for bash scripts.

 - Changing the Question model to add a language attribute.
 - Moving python_server.py -> code_server.py.
 - Adding functionality to test for Shell scripts.  This is still
   incomplete since the shell code checker seems to have some problems.
 - Modified the xmlrpc_clients to support multiple languages and right
   now two.
 - Using setgid/setuid instead of setegid/seteuid in the code_server.py..
 - Adding a bash example to the sample_questions.py.

The shell script support doesn't quite work yet but this is really a
code_server/checking issue.

1 files changed, 0 insertions, 117 deletions

diff --git a/python_server.py b/python_server.py
deleted file mode 100755
index d33ee47..0000000
--- a/python_server.py
+++ /dev/null
@@ -1,117 +0,0 @@
-#!/usr/bin/env python
-"""This server runs an XMLRPC server that can be submitted code and tests
-and returns the output.  It *should* be run as root and will run as the user 
-'nobody' so as to minimize any damange by errant code.  This can be configured 
-by editing settings.py to run as many servers as desired.  One can also
-specify the ports on the command line.  Here are examples::
-
-  $ sudo ./python_server.py
-  # Runs servers based on settings.py:SERVER_PORTS one server per port given.
-  
-or::
-
-  $ sudo ./python_server.py 8001 8002 8003 8004 8005
-  # Runs 5 servers on ports specified.
-
-All these servers should be running as nobody.
-"""
-import sys
-import traceback
-from SimpleXMLRPCServer import SimpleXMLRPCServer
-import pwd
-import os
-from os.path import isdir
-import signal
-from multiprocessing import Process
-
-# Local imports.
-from settings import SERVER_PORTS, SERVER_TIMEOUT
-
-
-def run_as_nobody():
-    """Runs the current process as nobody."""
-    # Set the effective uid to that of nobody.
-    nobody = pwd.getpwnam('nobody')
-    os.setegid(nobody.pw_gid)
-    os.seteuid(nobody.pw_uid)
-
-# Raised when the code times-out.
-# c.f. http://pguides.net/python/timeout-a-function
-class TimeoutException(Exception):
-    pass
-    
-def timeout_handler(signum, frame):
-    """A handler for the ALARM signal."""
-    raise TimeoutException('Code took too long to run.')
-
-
-def run_code(answer, test_code, in_dir=None):
-    """Tests given Python function (`answer`) with the `test_code` supplied.  
-    If the optional `in_dir` keyword argument is supplied it changes the 
-    directory to that directory (it does not change it back to the original when
-    done).  This function also timesout when the function takes more than 
-    SERVER_TIMEOUT seconds to run to prevent runaway code.
-
-    Returns
-    -------
-    
-    A tuple: (success, error message).
-    
-    """
-    if in_dir is not None and isdir(in_dir):
-        os.chdir(in_dir)
-        
-    # Add a new signal handler for the execution of this code.
-    old_handler = signal.signal(signal.SIGALRM, timeout_handler)
-    signal.alarm(SERVER_TIMEOUT)
-     
-    success = False
-    tb = None
-    try:
-        submitted = compile(answer, '<string>', mode='exec')
-        g = {}
-        exec submitted in g
-        _tests = compile(test_code, '<string>', mode='exec')
-        exec _tests in g
-    except TimeoutException:
-        err = 'Code took more than %s seconds to run.'%SERVER_TIMEOUT
-    except AssertionError:
-        type, value, tb = sys.exc_info()
-        info = traceback.extract_tb(tb)
-        fname, lineno, func, text = info[-1]
-        text = str(test_code).splitlines()[lineno-1]
-        err = "{0} {1} in: {2}".format(type.__name__, str(value), text)
-    except:
-        type, value = sys.exc_info()[:2]
-        err = "Error: {0}".format(repr(value))
-    else:
-        success = True
-        err = 'Correct answer'
-    finally:
-        del tb
-        # Set back any original signal handler.
-        signal.signal(signal.SIGALRM, old_handler) 
-        
-    # Cancel the signal if any, see signal.alarm documentation.
-    signal.alarm(0)
-
-    return success, err
-
-def run_server(port):
-    server = SimpleXMLRPCServer(("localhost", port))
-    server.register_function(run_code)
-    server.serve_forever()
-
-def main():
-    run_as_nobody()
-    if len(sys.argv) == 1:
-        ports = SERVER_PORTS
-    else:
-        ports = [int(x) for x in sys.argv[1:]]
-
-    for port in ports:
-        p = Process(target=run_server,  args=(port,))
-        p.start()
-    
-if __name__ == '__main__':
-    main()