ENH: Adding support for Multiple Choice Questions

Adds simple support for multiple choice questions that are also
auto-checked.  Many fixes to the templates and useful feature additions.
This changes the database.

4 files changed, 52 insertions, 28 deletions

diff --git a/exam/management/commands/dump_user_data.py b/exam/management/commands/dump_user_data.py
index f081565..6e0ca2a 100644
--- a/exam/management/commands/dump_user_data.py
+++ b/exam/management/commands/dump_user_data.py
@@ -34,12 +34,20 @@ Answers
 -------
 {% for question, answers in paper.get_question_answers.items %}
 Question: {{ question.id }}. {{ question.summary }} (Points: {{ question.points }})
+{% if question.type == "mcq" %}\
+###############################################################################
+Choices: {% for option in question.options.strip.splitlines %} {{option}}, {% endfor %}
+Student answer: {{ answers.0|safe }}
+{% else %}{# non-mcq questions #}\
 {% for answer in answers %}\
 ###############################################################################
-{{ answer.answer|safe }}
+{{ answer.answer.strip|safe }}
 # Autocheck: {{ answer.error|safe }}
-# Marks: {{ answer.marks }}
 {% endfor %}{# for answer in answers #}\
+{% endif %}\
+{% with answers|last as answer %}\
+Marks: {{answer.marks}}
+{% endwith %}\
 {% endfor %}{# for question, answers ... #}\
 
 Teacher comments
diff --git a/exam/management/commands/load_questions_xml.py b/exam/management/commands/load_questions_xml.py
index b4151ae..8bc2701 100644
--- a/exam/management/commands/load_questions_xml.py
+++ b/exam/management/commands/load_questions_xml.py
@@ -35,20 +35,24 @@ def load_questions_xml(filename):
         desc_node = question.getElementsByTagName("description")[0]
         description = (desc_node.childNodes[0].data).strip()
 
-        lang_node = question.getElementsByTagName("language")[0]
-        language = (lang_node.childNodes[0].data).strip()
+        type_node = question.getElementsByTagName("type")[0]
+        type = (type_node.childNodes[0].data).strip()
 
         points_node = question.getElementsByTagName("points")[0]
-        points = int((points_node.childNodes[0].data).strip()) \
-                 if points_node else 1
+        points = float((points_node.childNodes[0].data).strip()) \
+                 if points_node else 1.0
 
         test_node = question.getElementsByTagName("test")[0]
         test = decode_html((test_node.childNodes[0].data).strip())
 
+        opt_node = question.getElementsByTagName("options")[0]
+        opt = decode_html((opt_node.childNodes[0].data).strip())
+
         new_question = Question(summary=summary,
                                 description=description,
                                 points=points,
-                                language=language,
+                                options=opt,
+                                type=type,
                                 test=test)
         new_question.save()
     
diff --git a/exam/models.py b/exam/models.py
index ef4312f..717e02e 100644
--- a/exam/models.py
+++ b/exam/models.py
@@ -12,9 +12,10 @@ class Profile(models.Model):
     position = models.CharField(max_length=64)
 
 
-LANGUAGE_CHOICES = (
+QUESTION_TYPE_CHOICES = (
         ("python", "Python"),
         ("bash", "Bash"),
+        ("mcq", "MultipleChoice"),
         )
 
 ################################################################################
@@ -28,14 +29,16 @@ class Question(models.Model):
     description = models.TextField()
     
     # Number of points for the question.
-    points = models.IntegerField(default=1)
+    points = models.FloatField(default=1.0)
     
     # Test cases for the question in the form of code that is run.
-    # This is simple Python code.
-    test = models.TextField()
+    test = models.TextField(blank=True)
 
-    # The language being tested.
-    language = models.CharField(max_length=10, choices=LANGUAGE_CHOICES)
+    # Any multiple choice options.  Place one option per line.
+    options = models.TextField(blank=True)
+
+    # The type of question.
+    type = models.CharField(max_length=24, choices=QUESTION_TYPE_CHOICES)
 
     # Is this question active or not.  If it is inactive it will not be used
     # when creating a QuestionPaper.
diff --git a/exam/views.py b/exam/views.py
index ed73adf..e8e2e73 100644
--- a/exam/views.py
+++ b/exam/views.py
@@ -200,24 +200,31 @@ def check(request, q_id):
     new_answer = Answer(question=question, answer=answer, correct=False)
     new_answer.save()
     paper.answers.add(new_answer)
-        
-    # Otherwise we were asked to check.  We obtain the results via XML-RPC
-    # with the code executed safely in a separate process (the python_server.py)
-    # running as nobody.
-    user_dir = get_user_dir(user)
-    success, err_msg = code_server.run_code(answer, question.test, 
-                                            user_dir, question.language)
-    new_answer.error = err_msg
-
-    if success:
-        # Note the success and save it along with the marks.
-        new_answer.correct = success
-        new_answer.marks = question.points
+
+    # If we were not skipped, we were asked to check.  For any non-mcq
+    # questions, we obtain the results via XML-RPC with the code executed
+    # safely in a separate process (the code_server.py) running as nobody.
+    if question.type == 'mcq':
+        success = True # Only one attempt allowed for MCQ's.
+        if answer.strip() == question.test.strip():
+            new_answer.correct = True
+            new_answer.marks = question.points
+            new_answer.error = 'Correct answer'
+        else:
+            new_answer.error = 'Incorrect answer'
+    else:
+        user_dir = get_user_dir(user)
+        success, err_msg = code_server.run_code(answer, question.test, 
+                                                user_dir, question.type)
+        new_answer.error = err_msg
+        if success:
+            # Note the success and save it along with the marks.
+            new_answer.correct = success
+            new_answer.marks = question.points
 
     new_answer.save()
 
-    ci = RequestContext(request)
-    if not success:
+    if not success: # Should only happen for non-mcq questions.
         time_left = paper.time_left()
         if time_left == 0:
             return complete(request, reason='Your time is up!')
@@ -228,6 +235,7 @@ def check(request, q_id):
                    'paper': paper, 'last_attempt': answer,
                    'quiz_name': paper.quiz.description,
                    'time_left': time_left}
+        ci = RequestContext(request)
 
         return my_render_to_response('exam/question.html', context, 
                                      context_instance=ci)
@@ -271,6 +279,7 @@ def monitor(request, quiz_id=None):
         quiz = Quiz.objects.get(id=quiz_id)
     except Quiz.DoesNotExist:
         papers = []
+        quiz = None
     else:
         papers = QuestionPaper.objects.filter(quiz=quiz,
                                               user__profile__isnull=False)