Import Canvas grade book into OnTask

What do you think about adding in functionality to import the Canvas grade book directly into OnTask (similar to the SQL connections)?

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Hey @abelardopardo,

Thanks for all your work with the Canvas integration - now that it's done, I noticed there was a dearth of "big" new features in the issue list, so I thought I would contribute one.

I think this would be a valuable feature - it would really help getting more instructors on board that don't really want to futz around with uploading files every few days. Having the data imported and refresh with just a click (or even better, automatically on a schedule), would also help out with making the process a little more automatic. You can then imagine instructors could schedule outgoing emails at the beginning of the term and students would get weekly updates/emails about their progress (of course this has other implications with the conditions and thresholds being updated).

I had a look at the [roadmap](https://github.com/abelardopardo/ontask_b/blob/master/Roadmap.md) and I didn't see anything about this, so I hesitate to hijack things if you have other plans already.

Perhaps @anthonysymons (who was also interested in Canvas integration) could chime in on whether that would be useful for institutions beyond just ours?

I know when @craigdsthompson made a proposal for Canvas implementation, he sketched out a solution - I am unfortunately not technically inclined enough to do that. But perhaps he or @andrew-gardener could indicate whether this is possible or practical?

Thanks,

Firas

查看代码库中现有的 SQL 连接实现，以了解导入模式。检查已有的 Canvas 集成，以了解身份验证和 API 调用是如何处理的。确定 Canvas 成绩簿 API 的结构，并将其映射到 OnTask 的数据模型。概念验证将涉及创建一个新的导入模块，该模块很可能位于后端服务中。

由索引模型根据 Issue 内容生成。