Assignment API: 'submissions_download_url'.

[mlewis23]

I'd like to programmatically download the zip file of all the assignment submissions. In the data from the Assignment API there is a field for 'submissions_download_url'.  However, this url is not to a file. Instead, since it is the same url as seen on the 'Download Submissions' button in the GUI (https://[domain]/courses/[courseid]/assignments/[assignmentid]/submissions?zip=1) , I believe it is a webpage that runs javascript to create the file.  When this page tries to open, it no longer has the authentication of the API token, thus my saved zip file is of the SSO page.

So my questions is: Has anyone been able to work out how to download the zip file of all submissions from an assignment?

I'm using python, but I assume the solution is not going to be language dependent.

[mlewis23]

I did find a thread in the community very much related posted by  @raodm ​ (Is there an API to download contents (not metadata) of a file from a given assignment? ). But I'm not sure where the url was taken from. Is this from the Submissions API? Will that yield submissions for more than one user?

We are moving to a new plagiarism platform and we need to download all the papers that have been submitted to Canvas.

[mlewis23]

OK, found where the url came from:

https://[domain]/api/v1/courses/[courseid]/assignments/[assignmentid]/submissions

This yields a json file with attachment information. Maybe it is there, but I don't see this labeled anywhere in the documentation so here is an example of the data.

[{

"id": 999,

"body": null,

"url": null,

"grade": null,

"score": null,

"submitted_at": "2016-05-27T00:50:05Z",

"assignment_id": 9999,

"user_id": 99999,

"submission_type": "online_upload",

"workflow_state": "submitted",

"grade_matches_current_submission": true,

"graded_at": null,

"grader_id": null,

"attempt": 1,

"excused": null,

"late": true,

"preview_url": "https://[doamin]/courses/[courseid]/assignments/[assignmentid]/submissions/[otherid]?preview=1&versi...",

"attachments": [

{

"id": 999999,

"folder_id": 9999999,

"display_name": "file name.docx",

"filename": "filename.docx",

"content-type": "application/vnd.openxmlformats-officedocument.wordprocessingml.document",

"url": "https://[domain]/files/[courseid]/download?download_frd=1&verifier=[verifer hash]",

"size": 99,

"created_at": "2016-05-27T00:50:03Z",

"updated_at": "2016-05-27T00:50:05Z",

"unlock_at": null,

"locked": false,

"hidden": false,

"lock_at": null,

"hidden_for_user": false,

"thumbnail_url": null,

"modified_at": "2016-05-27T00:50:03Z",

"locked_for_user": false,

"preview_url": "/api/v1/crocodoc_session[other hash info]"}

]

},

]

I do really like the fact that the content-type, filename, and size are also available.

So at least now I do have a way of downloading all the documents, but I'd still prefer to be able to download a zip of all submissions rather than stepping through each submission for each assignment for each course for each term.

[pgo586]

I'm also interested in the same functionality. Please let us know if you've found a way to download a zip file with all the submissions via api call. Thanks!

[garth]

 @mlewis23  I have done something similar, stepping through assignments and submissions to collect information.

Sound like you're on the right path.

Have you considered creating an idea to add the zip option to an API call associated with downloading submissions?

Canvas seems to react to what the Community is hungry for, get people voting on it and maybe they'll make it.

This would be very useful for collection assignment submissions for accreditation review.

If you create the idea, I think people will vote for it.

[z_dusatko]

Hi there,

this thread is almost 2 years old any news on downloading all submissions as a zip file? I don't see any update in Canvas submission API.

Thanks,

Zbynek

[garth]

I have not heard anything more on this.

[themidiman]

I'm not sure if you've heard of the UCF Open source Canvasapi Python wrapper project... .

This discussion on the repo indicates that there is a way to get a file by file download for an assignment. I did a quick test of the concept and it works.

from canvasapi import Canvas
# Replace with your Canvas domain/URL
API_URL = "https://<yourcanvasdomain>.instructure.com"
# An instructor or admin token works for this code
API_KEY = input("Please Enter your API Key: ")

canvas = Canvas(API_URL, API_KEY)

# Replace with your specific course and assignment ids
course_id = 1327085
assignment_id = 14752902

course = canvas.get_course(course_id)

assignment = course.get_assignment(assignment_id)

subs = assignment.get_submissions()

ls = 0
for s in subs:
    print(f"-----\nls={ls}")
    if len(s.attachments) > 0:
        thefile = s.attachments[-1]
        # the files will download to the current directory where the code is being executed...
        thefile.download(f"a{s.assignment_id}_u{s.user_id}_{thefile}")
    ls+= 1

The only thing missing is the .zip format. It would be nice if the wrapper also did the work of putting it in .zip format. But Python can easily do that: https://realpython.com/python-zipfile/#creating-populating-and-extracting-your-own-zip-files

I strongly agree there should be a built-in API endpoint in the Canvas API for getting a zip file of student file submissions to an online assignment.