quizzer/answerdb.py

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