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, 30 insertions, 7 deletions

diff --git a/exam/xmlrpc_clients.py b/exam/xmlrpc_clients.py
index 115ee6e..01172d7 100644
--- a/exam/xmlrpc_clients.py
+++ b/exam/xmlrpc_clients.py
@@ -4,7 +4,7 @@ import random
 import socket
 
 
-class PythonServer(object):
+class CodeServer(object):
     """A class that manages accesing the farm of Python servers and making
     calls to them such that no one XMLRPC server is overloaded.
     """
@@ -12,19 +12,41 @@ class PythonServer(object):
         servers = [ServerProxy('http://localhost:%d'%(x)) for x in SERVER_PORTS]
         self.servers = servers
         self.indices = range(len(SERVER_PORTS))
+        self.methods = {"python": 'run_python_code',
+                        "bash": 'run_bash_code'}
     
-    def run_code(self, answer, test_code, user_dir):
-        """See the documentation of the method of the same name in 
-        python_server.py.
+    def run_code(self, answer, test_code, user_dir, language):
+        """Tests given code (`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).  The parameter language specifies which language to use for the
+        tests.
+
+        Parameters
+        ----------
+        answer : str
+            The user's answer for the question.
+        test_code : str
+            The test code to check the user code with.
+        user_dir : str (directory)
+            The directory to run the tests inside.
+        language : str
+            The programming language to use.
+
+        Returns
+        -------
+        A tuple: (success, error message).
         """
+        method_name = self.methods[language]
         done = False
-        result = [False, 'Unable to connect to any Python servers!']
+        result = [False, 'Unable to connect to any code servers!']
         # Try to connect a few times if not, quit.
         count = 5
         while (not done) and (count > 0):
             try:
                 server = self._get_server()
-                result = server.run_code(answer, test_code, user_dir)
+                method = getattr(server, method_name)
+                result = method(answer, test_code, user_dir)
             except socket.error:
                 count -= 1
             else:
@@ -38,4 +60,5 @@ class PythonServer(object):
 
 # views.py calls this Python server which forwards the request to one
 # of the running servers.
-python_server = PythonServer()
+code_server = CodeServer()
+