如果我的字典缺少必需的键，我应该提出哪种异常类型？

Question

I am testing that data (dictionary), used in Django's render(request, url, data) , has some required keys. I will raise an exception if the required keys are missing. What exception type is best suited for this?

Is there a better way to think about this?

Answer 1

For consistency with regular dicts, I would think a KeyError would be appropriate

>>> d = {'foo': 'bar'}
>>> d[5]
Traceback (most recent call last):
  File "<pyshell#1>", line 1, in <module>
    d[5]
KeyError: 5

KeyError

Raised when a mapping (dictionary) key is not found in the set of existing keys.