added upload and download questions with files

2 files changed, 72 insertions, 18 deletions

diff --git a/yaksh/models.py b/yaksh/models.py
index 73d4b27..d626b26 100644
--- a/yaksh/models.py
+++ b/yaksh/models.py
@@ -10,9 +10,13 @@ from django.forms.models import model_to_dict
 from django.contrib.contenttypes.models import ContentType
 from taggit.managers import TaggableManager
 from django.utils import timezone
+from django.core.files import File
+from StringIO import StringIO
 import pytz
 import os
 import shutil
+import zipfile
+
 
 languages = (
         ("python", "Python"),
@@ -231,27 +235,32 @@ class Question(models.Model):
     def dump_into_json(self, question_ids, user):
         questions = Question.objects.filter(id__in=question_ids, user_id=user.id)
         questions_dict = []
+        zip_file_name = StringIO()
+        zip_file = zipfile.ZipFile(zip_file_name, "a")
         for question in questions:
             test_case = question.get_test_cases()
+            files = question._add_and_get_files(zip_file)
             q_dict = {'summary': question.summary,
                       'description': question.description,
-                      'points': question.points,
-                      'language': question.language,
-                      'type': question.type,
-                      'active': question.active,
+                      'points': question.points, 'language': question.language,
+                      'type': question.type, 'active': question.active,
                       'test_case_type': question.test_case_type,
                       'snippet': question.snippet,
-                      'testcase': [case.get_field_value() for case in test_case]}
+                      'testcase': [case.get_field_value() for case in test_case],
+                      'files': files}
             questions_dict.append(q_dict)
-
-        return json.dumps(questions_dict, indent=2)
+        question._add_json_to_zip(zip_file, questions_dict)
+        return zip_file_name
 
     def load_from_json(self, questions_list, user):
         questions = json.loads(questions_list)
+        ques = Question()
         for question in questions:
             question['user'] = user
+            files = question.pop('files')
             test_cases = question.pop('testcase')
             que, result = Question.objects.get_or_create(**question)
+            que._add_files_to_db(files)
             model_class = get_model_class(que.test_case_type)
             for test_case in test_cases:
                 model_class.objects.get_or_create(question=que, **test_case)
@@ -278,6 +287,29 @@ class Question(models.Model):
 
         return test_case
 
+    def _add_and_get_files(self, zip_file):
+        files = FileUpload.objects.filter(question=self)
+        for file in files:
+            zip_file.write(file.file.path, (os.path.basename(file.file.path)))
+        files_list = [os.path.basename(file.file.name) for file in files]
+        return files_list
+
+    def _add_files_to_db(self, files):
+        if files:
+            for file_name in files:
+                file = open(file_name, 'r')
+                django_file = File(file)
+                f = FileUpload.objects.get_or_create(file=django_file, question=self)
+                os.remove(file_name)
+
+    def _add_json_to_zip(self, zip_file, q_dict):
+        json_data = json.dumps(q_dict, indent=2)
+        with open("questions_dump.json", "w") as json_file:
+            json_file.write(json_data)
+        zip_file.write(json_file.name)
+        zip_file.close()
+        os.remove(json_file.name)
+
     def __unicode__(self):
         return self.summary
 
diff --git a/yaksh/views.py b/yaksh/views.py
index e1ec44e..87e6005 100644
--- a/yaksh/views.py
+++ b/yaksh/views.py
@@ -22,6 +22,7 @@ import pytz
 from taggit.models import Tag
 from itertools import chain
 import json
+import zipfile
 
 # Local imports.
 from yaksh.models import get_model_class, Quiz, Question, QuestionPaper, QuestionSet, Course
@@ -73,6 +74,7 @@ def is_moderator(user):
     if user.groups.filter(name='moderator').exists():
         return True
 
+
 def add_to_group(users):
     """ add users to moderator group """
     group = Group.objects.get(name="moderator")
@@ -80,6 +82,22 @@ def add_to_group(users):
         if not is_moderator(user):
             user.groups.add(group)
 
+
+def extract_files(questions_file):
+    if zipfile.is_zipfile(questions_file):
+        zip_file = zipfile.ZipFile(questions_file, 'r')
+        zip_file.extractall()
+
+
+def read_json(json_file, user):
+    question = Question()
+    if os.path.exists(json_file):
+        with open(json_file, 'r') as q_file:
+            questions_list = q_file.read()
+            question.load_from_json(questions_list, user)
+            os.remove(json_file)
+
+
 def index(request):
     """The start page.
     """
@@ -663,9 +681,11 @@ def courses(request):
     ci = RequestContext(request)
     if not is_moderator(user):
         raise Http404('You are not allowed to view this page')
-    courses = Course.objects.filter(creator=user, is_trial=False)
+    demo_user = User.objects.get(username="demo_user")
+    courses = Course.objects.filter(Q(creator=user) | Q(creator=demo_user),
+                                    is_trial=False)
     return my_render_to_response('yaksh/courses.html', {'courses': courses},
-                                context_instance=ci)
+                                 context_instance=ci)
 
 
 @login_required
@@ -869,22 +889,24 @@ def show_all_questions(request):
             form = UploadFileForm(request.POST, request.FILES)
             if form.is_valid():
                 questions_file = request.FILES['file']
-                if questions_file.name.split('.')[-1] == "json":
-                    questions_list = questions_file.read()
-                    question = Question()
-                    question.load_from_json(questions_list, user)
+                file_name = questions_file.name.split('.')
+                if file_name[-1] == "zip":
+                    extract_files(questions_file)
+                    read_json("questions_dump.json", user)
                 else:
-                    message = "Please Upload a JSON file"
+                    message = "Please Upload a ZIP file"
                     context['message'] = message
 
         if request.POST.get('download') == 'download':
             question_ids = request.POST.getlist('question')
             if question_ids:
                 question = Question()
-                questions = question.dump_into_json(question_ids, user)
-                response = HttpResponse(questions, content_type='text/json')
-                response['Content-Disposition'] = 'attachment; filename=\
-                                            "{0}_questions.json"'.format(user)
+                zip_file = question.dump_into_json(question_ids, user)
+                response = HttpResponse(content_type='application/zip')
+                response['Content-Disposition'] = '''attachment;\
+                                          filename={0}_questions.zip'''.format(user)
+                zip_file.seek(0)
+                response.write(zip_file.read())
                 return response
             else:
                 context['msg'] = "Please select atleast one question to download"