quizzer/answerdb.py

   1 # Copyright
   2
   3 import codecs as _codecs
   4 import json as _json
   5
   6 from . import __version__
   7
   8
   9 class AnswerDatabase (dict):
  10     def __init__(self, path=None, encoding=None):
  11         super(AnswerDatabase, self).__init__()
  12         self.path = path
  13         self.encoding = encoding
  14
  15     def _open(self, mode='r', path=None, encoding=None):
  16         if path:
  17             self.path = path
  18         if encoding:
  19             self.encoding = encoding
  20         return _codecs.open(self.path, mode, self.encoding)
  21
  22     def load(self, **kwargs):
  23         with self._open(mode='r', **kwargs) as f:
  24             data = _json.load(f)
  25         version = data.get('version', None)
  26         if version != __version__:
  27             raise NotImplementedError('upgrade from {} to {}'.format(
  28                     version, __version__))
  29         self.update(data['answers'])
  30
  31     def save(self, **kwargs):
  32         data = {
  33             'version': __version__,
  34             'answers': self,
  35             }
  36         with self._open(mode='w', **kwargs) as f:
  37             _json.dump(
  38                 data, f, indent=2, separators=(',', ': '), sort_keys=True)
  39             f.write('\n')
  40
  41     def add(self, question, answer, correct):
  42         if question.id not in self:
  43             self[question.id] = []
  44         self[question.id].append({
  45                 'answer': answer,
  46                 'correct': correct,
  47                 })
  48
  49     def get_answered(self, questions):
  50         return [q for q in questions if q.id in self]
  51
  52     def get_unanswered(self, questions):
  53         return [q for q in questions if q.id not in self]
  54
  55     def get_correctly_answered(self, questions):
  56         return [q for q in questions
  57                 if True in [a['correct'] for a in self.get(q.id, [])]]
  58
  59     def get_never_correctly_answered(self, questions):
  60         return [q for q in questions
  61                 if True not in [a['correct'] for a in self.get(q.id, [])]]