Create assignment API creating duplicates

[walter_yuan]

The create assignment API

POST /api/v1/courses/:course_id/assignments

seems to create two duplicate assignments (instead of one) every time I call it. Has anyone else experienced this or can anyone help with this?

[maguire]

@ @walter_yuan   I have not seen this happen. The basic code I use for this (in python) is:

access_token=configuration["canvas"]["access_token"]
baseUrl="https://"+configuration["canvas"]["host"]+"/api/v1/courses/"

header = {'Authorization' : 'Bearer ' + access_token}
payload = {}

----------------------------------------------------------------------
def create_assignment(course_id, name, max_points, grading_type, description):

    # Use the Canvas API to create an assignment
    # POST /api/v1/courses/:course_id/assignments

    url = baseUrl + '%s/assignments' % (course_id)
    if Verbose_Flag:
       print("url: " + url)

    payload={'assignment[name]': name,
             'assignment[submission_types][]': ["none"],
             'assignment[peer_reviews]': False,
             'assignment[notify_of_update]': False,
             'assignment[grade_group_students_individually]': True,
             'assignment[points_possible]': max_points,
             'assignment[grading_type]': grading_type,
             'assignment[description]': description,
             'assignment[published]': True # if not published it will not be in the gradebook
    }

    r = requests.post(url, headers = header, data=payload)
    if r.status_code == requests.codes.ok:
       if r.status_code == requests.codes.ok:
           page_response=r.json()
           print("inserted assignment")
           return True
    return False

I have not  created a large number of assignments this way, but will do so over the next few days.

[walter_yuan · Accepted solution]

Thanks for the quick response! We have figured it out. It turns out we had implemented a retry system on any response that wasn't a 200. Creating an assignment actually returns a 201 so that triggered a retry in our system. We just amended it to accept any 2xx response as working.

[maguire]

@ @walter_yuan  

Yes, one must be careful when you have automatic retries to check the return value.  When I was using a program to put in thousands of quiz questions I found that I need to use not only a retry mechanism, but also I added an exponential backoff - to deal with the rate limiting of the RESTful API and the fact that in the test instance I was getting 503 responses once and while.