Merge pull request #180 from MITx/kimth/lms-coderesponse

CodeResponse for external/queued grading of student code

common/lib/capa/capa/capa_problem.py

@@ -179,6 +179,15 @@ class LoncapaProblem(object):
             return {'score': correct,
                     'total': self.get_max_score()}
 
+    def update_score(self, score_msg):
+        newcmap = CorrectMap()
+        for responder in self.responders.values():
+            if hasattr(responder,'update_score'): # Is this the best way to implement 'update_score' for CodeResponse?
+                results = responder.update_score(score_msg)         
+                newcmap.update(results)
+        self.correct_map = newcmap
+        return newcmap
+
     def grade_answers(self, answers):
         '''
         Grade student responses.  Called by capa_module.check_problem.

common/lib/capa/capa/responsetypes.py

@@ -18,6 +18,7 @@ import re
 import requests
 import traceback
 import abc
+import time
 
 # specific library imports
 from calc import evaluator, UndefinedVariable
@@ -693,6 +694,124 @@ class SymbolicResponse(CustomResponse):
 
 #-----------------------------------------------------------------------------
 
+class CodeResponse(LoncapaResponse):
+    ''' 
+    Grade student code using an external server
+    '''
+
+    response_tag = 'coderesponse'
+    allowed_inputfields = ['textline', 'textbox']
+
+    def setup_response(self):
+        xml = self.xml
+        self.url = xml.get('url') or "http://ec2-50-16-59-149.compute-1.amazonaws.com/xqueue/submit/" # FIXME -- hardcoded url
+
+        answer = xml.find('answer')
+        if answer is not None:
+            answer_src = answer.get('src')
+            if answer_src is not None:
+                self.code = self.system.filesystem.open('src/'+answer_src).read()
+            else:
+                self.code = answer.text
+        else:					# no <answer> stanza; get code from <script>
+            self.code = self.context['script_code']
+            if not self.code:
+                msg = '%s: Missing answer script code for externalresponse' % unicode(self)
+                msg += "\nSee XML source line %s" % getattr(self.xml,'sourceline','<unavailable>')
+                raise LoncapaProblemError(msg)
+
+        self.tests = xml.get('tests')
+
+    def get_score(self, student_answers):
+        idset = sorted(self.answer_ids)
+        
+        try:
+            submission = [student_answers[k] for k in idset]
+        except Exception as err:
+            log.error('Error in CodeResponse %s: cannot get student answer for %s; student_answers=%s' % (err, self.answer_ids, student_answers))
+            raise Exception(err)
+
+        self.context.update({'submission': submission})
+        extra_payload = {'edX_student_response': json.dumps(submission)}
+
+        # Should do something -- like update the problem state -- based on the queue response
+        r = self._send_to_queue(extra_payload)
+        
+        return CorrectMap() 
+
+    def update_score(self, score_msg):
+        # Parse 'score_msg' as XML
+        try:
+            rxml = etree.fromstring(score_msg)
+        except Exception as err:
+            msg = 'Error in CodeResponse %s: cannot parse response from xworker r.text=%s' % (err, score_msg)
+            raise Exception(err)
+
+        # The following process is lifted directly from ExternalResponse
+        idset = sorted(self.answer_ids)
+        cmap = CorrectMap()
+        ad = rxml.find('awarddetail').text
+        admap = {'EXACT_ANS':'correct',         # TODO: handle other loncapa responses
+                 'WRONG_FORMAT': 'incorrect',
+                 }
+        self.context['correct'] = ['correct']
+        if ad in admap:
+            self.context['correct'][0] = admap[ad]
+
+        # create CorrectMap
+        for key in idset:
+            idx = idset.index(key)
+            msg = rxml.find('message').text.replace('&nbsp;','&#160;') if idx==0 else None
+            cmap.set(key, self.context['correct'][idx], msg=msg)
+        
+        return cmap
+
+    # CodeResponse differentiates from ExternalResponse in the behavior of 'get_answers'. CodeResponse.get_answers
+    #   does NOT require a queue submission, and the answer is computed (extracted from problem XML) locally.
+    def get_answers(self):
+        # Extract the CodeResponse answer from XML
+        penv = {}
+        penv['__builtins__'] = globals()['__builtins__']
+        try:
+            exec(self.code,penv,penv)
+        except Exception as err:
+            log.error('Error in CodeResponse %s: Error in problem reference code' % err)
+            raise Exception(err)
+        try:
+            ans = penv['answer']
+        except Exception as err:
+            log.error('Error in CodeResponse %s: Problem reference code does not define answer in <answer>...</answer>' % err)
+            raise Exception(err)
+
+        anshtml = '<font color="blue"><span class="code-answer"><br/><pre>%s</pre><br/></span></font>' % ans
+        return dict(zip(self.answer_ids,[anshtml]))
+
+    # CodeResponse._send_to_queue implements the same interface as defined for ExternalResponse's 'get_score'
+    def _send_to_queue(self, extra_payload):
+        # Prepare payload
+        xmlstr = etree.tostring(self.xml, pretty_print=True)
+        header = { 'return_url': self.system.xqueue_callback_url }
+        header.update({'timestamp': time.time()})
+        payload = {'xqueue_header': json.dumps(header), # 'xqueue_header' should eventually be derived from xqueue.queue_common.HEADER_TAG or something similar
+                   'xml': xmlstr,
+                   'edX_cmd': 'get_score',
+                   'edX_tests': self.tests,
+                   'processor': self.code,
+                  }
+        payload.update(extra_payload)
+
+        # Contact queue server
+        try:
+            r = requests.post(self.url, data=payload)
+        except Exception as err:
+            msg = "Error in CodeResponse %s: cannot connect to queue server url=%s" % (err, self.url)
+            log.error(msg)
+            raise Exception(msg)
+
+        return r
+
+#-----------------------------------------------------------------------------
+
 class ExternalResponse(LoncapaResponse):
     '''
     Grade the students input using an external server.
@@ -1072,5 +1191,5 @@ class ImageResponse(LoncapaResponse):
 # TEMPORARY: List of all response subclasses
 # FIXME: To be replaced by auto-registration
 
-__all__ = [ NumericalResponse, FormulaResponse, CustomResponse, SchematicResponse, MultipleChoiceResponse, TrueFalseResponse, ExternalResponse, ImageResponse, OptionResponse, SymbolicResponse, StringResponse ]
+__all__ = [ CodeResponse, NumericalResponse, FormulaResponse, CustomResponse, SchematicResponse, MultipleChoiceResponse, TrueFalseResponse, ExternalResponse, ImageResponse, OptionResponse, SymbolicResponse, StringResponse ]
 

common/lib/xmodule/xmodule/capa_module.py

@@ -275,6 +275,7 @@ class CapaModule(XModule):
             'problem_reset': self.reset_problem,
             'problem_save': self.save_problem,
             'problem_show': self.get_answer,
+            'score_update': self.update_score,
             }
 
         if dispatch not in handlers:
@@ -321,6 +322,12 @@ class CapaModule(XModule):
         #TODO: Not 404
         raise self.system.exception404
 
+    def update_score(self, get):
+        score_msg = get['response']
+        self.lcp.update_score(score_msg)
+
+        return dict() # No AJAX return is needed
+
     def get_answer(self, get):
         '''
         For the "show answer" button.

lms/djangoapps/courseware/module_render.py

@@ -28,7 +28,7 @@ class I4xSystem(object):
     '''
     def __init__(self, ajax_url, track_function,
                  get_module, render_template, replace_urls,
-                 user=None, filestore=None):
+                 user=None, filestore=None, xqueue_callback_url=None):
         '''
         Create a closure around the system environment.
 
@@ -48,6 +48,7 @@ class I4xSystem(object):
             that capa_module can use to fix up the static urls in ajax results.
         '''
         self.ajax_url = ajax_url
+        self.xqueue_callback_url = xqueue_callback_url
         self.track_function = track_function
         self.filestore = filestore
         self.get_module = get_module
@@ -207,6 +208,7 @@ def get_module(user, request, location, student_module_cache, position=None):
 
     # Setup system context for module instance
     ajax_url = settings.MITX_ROOT_URL + '/modx/' + descriptor.location.url() + '/'
+    xqueue_callback_url = settings.MITX_ROOT_URL + '/xqueue/' + user.username + '/' + descriptor.location.url() + '/'
 
     def _get_module(location):
         (module, _, _, _) = get_module(user, request, location, student_module_cache, position)
@@ -218,6 +220,7 @@ def get_module(user, request, location, student_module_cache, position=None):
     system = I4xSystem(track_function=make_track_function(request),
                        render_template=render_to_string,
                        ajax_url=ajax_url,
+                       xqueue_callback_url=xqueue_callback_url,
                        # TODO (cpennington): Figure out how to share info between systems
                        filestore=descriptor.system.resources_fs,
                        get_module=_get_module,
@@ -321,6 +324,53 @@ def add_histogram(module):
     module.get_html = get_html
     return module
 
+# THK: TEMPORARY BYPASS OF AUTH!
+from django.views.decorators.csrf import csrf_exempt
+from django.contrib.auth.models import User
+@csrf_exempt
+def xqueue_callback(request, username, id, dispatch):
+    # Parse xqueue response
+    get = request.POST.copy()
+    try:
+        header = json.loads(get.pop('xqueue_header')[0]) # 'dict'
+    except Exception as err:
+        msg = "Error in xqueue_callback %s: Invalid return format" % err
+        raise Exception(msg)
+    
+    # Should proceed only when the request timestamp is more recent than problem timestamp
+    timestamp = header['timestamp']
+
+    # Retrieve target StudentModule
+    user = User.objects.get(username=username)
+
+    student_module_cache = StudentModuleCache(user, modulestore().get_item(id))
+    instance, instance_module, shared_module, module_type = get_module(request.user, request, id, student_module_cache)
+    
+    if instance_module is None:
+        log.debug("Couldn't find module '%s' for user '%s'",
+                  id, request.user)
+        raise Http404
+    
+    oldgrade = instance_module.grade
+    old_instance_state = instance_module.state
+
+    # We go through the "AJAX" path
+    #   So far, the only dispatch from xqueue will be 'score_update'
+    try:
+        ajax_return = instance.handle_ajax(dispatch, get) # Can ignore the "ajax" return in 'xqueue_callback'
+    except:
+        log.exception("error processing ajax call")
+        raise
+
+    # Save state back to database
+    instance_module.state = instance.get_instance_state()
+    if instance.get_score():
+        instance_module.grade = instance.get_score()['score']
+    if instance_module.grade != oldgrade or instance_module.state != old_instance_state:
+        instance_module.save()
+
+    return HttpResponse("")
+
 def modx_dispatch(request, dispatch=None, id=None):
     ''' Generic view for extensions. This is where AJAX calls go.
 
@@ -339,7 +389,7 @@ def modx_dispatch(request, dispatch=None, id=None):
 
     student_module_cache = StudentModuleCache(request.user, modulestore().get_item(id))
     instance, instance_module, shared_module, module_type = get_module(request.user, request, id, student_module_cache)
-
+    
     if instance_module is None:
         log.debug("Couldn't find module '%s' for user '%s'",
                   id, request.user)

lms/urls.py

@@ -58,6 +58,7 @@ if settings.COURSEWARE_ENABLED:
         url(r'^masquerade/', include('masquerade.urls')),
         url(r'^jumpto/(?P<probname>[^/]+)/$', 'courseware.views.jump_to'),
         url(r'^modx/(?P<id>.*?)/(?P<dispatch>[^/]*)$', 'courseware.module_render.modx_dispatch'), #reset_problem'),
+        url(r'^xqueue/(?P<username>[^/]*)/(?P<id>.*?)/(?P<dispatch>[^/]*)$', 'courseware.module_render.xqueue_callback'),
         url(r'^change_setting$', 'student.views.change_setting'),
         url(r'^s/(?P<template>[^/]*)$', 'static_template_view.views.auth_index'),
         url(r'^book/(?P<page>[^/]*)$', 'staticbook.views.index'),