Every day thru Rest API call I am getting data for Assignment Submission API and suprisingly some day rows increases and decreses which is wierd or is it how it works?
How to track that? Could there be any particular reason for that?
I'm not sure I exactly follow what you're saying. Are you saying that the number of rows downloaded varies each day or that there is some information that is there on some days that isn't there on other days or something else? You also didn't say which API call you were using -- submissions for a single assignment or submissions for multiple assignments. The multiple submissions one is more powerful, but comes with some potential issues if you don't understand the query parameters fully.
Submissions entries are created when the assignment is created. If you have a class with 50 students and 10 assignments, there are 500 submission entries. Submission entries will change as student submit information, but the number of submission entries will remain constant unless the number of students or the number of assignments change. Changing the number of students may include marking student enrollments as completed, inactive, or deleted. It doesn't have to be an additional enrollment.
There are all kinds of options that control which information is downloaded.
If those things don't answer the question, then sharing exactly which API you're calling and what parameters you're calling it with may allow us to provide additional insight..
Hi James Jones
I am finiding course id and assignment id from the below SQL query and then using this to pass it to "https://swinburneonline.instructure.com/api/v1/courses/"course_id+"/assignments/"+assignment_id+"/submissions?per_page=100" URL and until last page URL changes.
select distinct cd.canvas_id as course_id, ad.canvas_id as assignment_id
from canvas_data_sut.assignment_dim ad
inner join canvas_data_sut.course_dim cd on (cd.id = ad.course_id)
inner join canvas_data_sut.enrollment_term_dim etd on (etd.id = cd.enrollment_term_id)
left join canvas_data_sut.quiz_dim qd on (qd.assignment_id = ad.id)
where etd.name in
select distinct etd.name from landing.saas_canvas_enrollment_term_dim_history etd
left join presentation.dim_date_final dd on dd.teaching_period = right(etd.name,4) + ' TP' + right(split_part(etd.name,',',1),1)
WHERE dd.partner_id=1 and current_date=full_date
) -- Basically find current TP
and cd.workflow_state != 'deleted'
and ad.workflow_state != 'deleted'
and lower(ad.title) not in ('originality report submission', 'student confidentiality agreement')
order by course_id
Not sure if I am doing something wrong.
until last page URL changes
What do you mean by this?
When handling pagination, you should focus on the next page rather than the last page. When bookmarks are used for pagination, the last is missing. As long as there is a next page, you should continue fetching it. When you get to the last page, the next link header disappears.
I try to cheat the system sometimes and use the last page to tell me how many requests I should make using the page= option and then I can make the requests in parallel. However, that approach will not work when bookmarks are used.
My class only has 48 students in it, which wasn't enough for the single-assignment API call that you're using to kick in the bookmarks. I checked another course that had 1458 submissions for a single assignment and it didn't go to the bookmark approach either. It may be because of a low server load or it may be safe to do page=2&per_page=100, page=3&per_page=100, etc, until you get to the point where there is no next page left. If you follow the links sequentially (not in parallel), the approach of using the value in the next link header will work whether it uses bookmarks or not. When I try to game the system, I check the format of the next page header to see if it's returning page numbers or bookmarks and only use the cheat when it's returning numbers.
There is another potential issue going on. Back in 2015 there was this thread: https://community.canvaslms.com/message/4115 When per_page=100 was used, it wasn't returning all of the rows and some of them were being returned twice. Changing the per_page value seemed to fix it, at least in that case. I thought Canvas had fixed the issue, but sometimes issues pop back into the mix.
Thanks for the quick reply.
Yes I am iterating to next page until last page is found so in that way it would be alright. What I suspect is as you rightly mentioned some student enrolments getting inactive or withdrawn which might be reducing number of records. I will still double check.
Thanks a lot for your pointers.