Can I use Canvas grading engine to know if a submitted answer is correct before the quiz is turned i

[chrisrockwell]

I have an LTI Tool that delivers questions to users via a custom UI.  I need to be able to tell, in real-time, if the answers are correct - the flow is something like this:

- User answers question

- User is given feedback on whether or not answer was correct

- User is given another question

From what I have found I am unable to use Canvas API to know if a question is correct without completing the quiz submission.  I do post the quiz submission question, but Canvas does not return whether or not that is correct.

[Edit] - I've found where the grading happens -> app/models/quizzes/quiz_question/[question_type]
Additionally, if I'm unable to use the Canvas grading engine, can anyone point me to the code within the open source project (tests or implementation) so that if I do write my own, I'm following all the rules?  I'm not familiar with Ruby and haven't had luck browsing the project to find what I need: https://github.com/instructure/canvas-lms