pregenerates tests for all students

use raise from pattern to chain exception stack trace add function to print test (incomplete)

pregenerates tests for all students
use raise from pattern to chain exception stack trace add function to print test (incomplete)
Miguel Barão
1 parent 2e43c7a2
Showing 3 changed files with 64 additions and 27 deletions Show diff stats
perguntations/app.py
perguntations/serve.py
perguntations/test.py
@@ -88,6 +88,7 @@ class App():
         self.allowed = set()    # '0' is hardcoded to allowed elsewhere
         self.unfocus = set()    # set of students that have no browser focus
         self.area = dict()      # {uid: percent_area}
+        self.pregenerated_tests = []  # list of tests to give to students
         self._make_test_factory(conf)
@@ -99,11 +100,15 @@ class App():
         try:
             with self.db_session() as sess:
                 num = sess.query(Student).filter(Student.id != '0').count()
-        except Exception:
-            raise AppException(f'Database unusable {dbfile}.')
-
+        except Exception as exc:
+            raise AppException(f'Database unusable {dbfile}.') from exc
         logger.info('Database "%s" has %s students.', dbfile, num)
+        # pre-generate tests
+        logger.info('Generating tests for %d students:', num)
+        self._pregenerate_tests(num)
+        logger.info('Tests are ready.')
+
         # command line option --allow-all
         if conf['allow_all']:
             self.allow_all_students()
@@ -159,10 +164,12 @@ class App():
         try:
             testconf = load_yaml(conf['testfile'])
         except Exception as exc:
-            logger.critical('Error loading test configuration YAML.')
-            raise AppException(exc)
+            msg = 'Error loading test configuration YAML.'
+            logger.critical(msg)
+            raise AppException(msg) from exc
-        testconf.update(conf)  # command line options override configuration
+        # command line options override configuration
+        testconf.update(conf)
         # start test factory
         logger.info('Making test factory...')
@@ -170,23 +177,38 @@ class App():
             self.testfactory = TestFactory(testconf)
         except TestFactoryException as exc:
             logger.critical(exc)
-            raise AppException('Failed to create test factory!')
+            raise AppException('Failed to create test factory!') from  exc
         logger.info('Test factory ready. No errors found.')
     # ------------------------------------------------------------------------
+    def _pregenerate_tests(self, n):
+        for _ in range(n):
+            event_loop = asyncio.get_event_loop()
+            test = event_loop.run_until_complete(self.testfactory.generate())
+            self.pregenerated_tests.append(test)
+            print(test)
+
+    # ------------------------------------------------------------------------
     async def generate_test(self, uid):
         '''generate a test for a given student'''
         if uid in self.online:
-            logger.info('"%s" generating new test.', uid)
+            try:
+                test = self.pregenerated_tests.pop()
+            except IndexError:
+                logger.info('"%s" generating new test.', uid)
+                test = await self.testfactory.generate()  # student_id) FIXME
+            else:
+                logger.info('"%s" using pregenerated test.', uid)
+
             student_id = self.online[uid]['student']  # {number, name}
-            test = await self.testfactory.generate(student_id)
+            test.start(student_id)
             self.online[uid]['test'] = test
             logger.info('"%s" test is ready.', uid)
             return self.online[uid]['test']
-        # this implies an error in the code. should never be here!
-        logger.critical('"%s" offline, can\'t generate test', uid)
+        # this implies an error in the program, code should be unreachable!
+        logger.critical('"%s" is offline, can\'t generate test', uid)
     # ------------------------------------------------------------------------
     async def correct_test(self, uid, ans):
@@ -410,7 +432,8 @@ class App():
     def allow_all_students(self):
         '''allow all students to login'''
-        self.allowed.update(s[0] for s in self._get_all_students())
+        all_students = self._get_all_students()
+        self.allowed.update(s[0] for s in all_students)
         logger.info('Allowed all students.')
     def deny_all_students(self):
@@ -383,6 +383,7 @@ class TestHandler(BaseHandler):
     '''
     _templates = {
+        # -- question templates --
         'radio':        'question-radio.html',
         'checkbox':     'question-checkbox.html',
         'text':         'question-text.html',
@@ -406,6 +407,7 @@ class TestHandler(BaseHandler):
         test = self.testapp.get_student_test(uid)  # reloading returns same test
         if test is None:
             test = await self.testapp.generate_test(uid)
+
         self.render('test.html', t=test, md=md_to_html, templ=self._templates)
     # --- POST
@@ -152,9 +152,9 @@ class TestFactory(dict):
         try:
             with open(testfile, 'w') as file:
                 file.write('You can safely remove this file.')
-        except OSError:
+        except OSError as exc:
             msg = f'Cannot write answers to directory "{self["answers_dir"]}"'
-            raise TestFactoryException(msg)
+            raise TestFactoryException(msg) from exc
     def check_questions_directory(self):
         '''Check if questions directory is missing or not accessible.'''
@@ -223,16 +223,16 @@ class TestFactory(dict):
         self.check_grade_scaling()
     # ------------------------------------------------------------------------
-    async def generate(self, student):
+    async def generate(self):  #, student):
         '''
         Given a dictionary with a student dict {'name':'john', 'number': 123}
         returns instance of Test() for that particular student
         '''
         # make list of questions
-        test = []
-        qnum = 1     # track question number
-        nerr = 0  # count errors generating questions
+        questions = []
+        qnum = 1  # track question number
+        nerr = 0  # count errors during questions generation
         for qlist in self['questions']:
             # choose one question variant
@@ -255,28 +255,28 @@ class TestFactory(dict):
                 question['number'] = qnum  # counter for non informative panels
                 qnum += 1
-            test.append(question)
+            questions.append(question)
         # setup scale
-        total_points = sum(q['points'] for q in test)
+        total_points = sum(q['points'] for q in questions)
         if total_points > 0:
             # normalize question points to scale
             if self['scale'] is not None:
                 scale_min, scale_max = self['scale']
-                for question in test:
+                for question in questions:
                     question['points'] *= (scale_max - scale_min) / total_points
             else:
                 self['scale'] = [0, total_points]
         else:
             logger.warning('Total points is **ZERO**.')
             if self['scale'] is None:
-                self['scale'] = [0, 20]
+                self['scale'] = [0, 20]  # default
         if nerr > 0:
             logger.error('%s errors found!', nerr)
-        # these will be copied to the test instance
+        # copy these from the test configuratoin to each test instance
         inherit = {'ref', 'title', 'database', 'answers_dir',
                    'questions_dir', 'files',
                    'duration', 'autosubmit',
@@ -284,9 +284,7 @@ class TestFactory(dict):
                    'show_ref', 'debug', }
         # NOT INCLUDED:  testfile, allow_all, review
-        return Test({
-            **{'student': student, 'questions': test},
-            **{k:self[k] for k in inherit}})
+        return Test({'questions': questions, **{k:self[k] for k in inherit}})
     # ------------------------------------------------------------------------
     def __repr__(self):
@@ -303,6 +301,13 @@ class Test(dict):
     # ------------------------------------------------------------------------
     def __init__(self, d):
         super().__init__(d)
+
+    # ------------------------------------------------------------------------
+    def start(self, student):
+        '''
+        Write student id in the test and register start time
+        '''
+        self['student'] = student
         self['start_time'] = datetime.now()
         self['finish_time'] = None
         self['state'] = 'ACTIVE'
@@ -346,5 +351,12 @@ class Test(dict):
         self['finish_time'] = datetime.now()
         self['state'] = 'QUIT'
         self['grade'] = 0.0
-        logger.info('Student %s:  gave up.', self["student"]["number"])
+        # logger.info('Student %s:  gave up.', self["student"]["number"])
         return self['grade']
+
+    # ------------------------------------------------------------------------
+    def __str__(self):
+        return ('Test:\n'
+                f'  student:  {self.get("student", "--")}\n'
+                f'  start_time:  {self.get("start_time", "--")}\n'
+                f'  questions:  {", ".join(q["ref"] for q in self["questions"])}\n')