API problem: attachments in create conversations

[josh3]

I'm trying to use the Canvas REST API to automate the sending of emails on student progress,  that is sending "Conversations" to users. I can do so successfully without attachments, but when I try to include an attachment, which has been uploaded to my “conversation attachments” folder, it gives me a response 500 error. 

To try to make sure that I'm doing this correctly, I've done the following.

1. I first manually send a test email and attach an attachment which is a png file of size roughly 20KB. The attachment gets uploaded to my "conversation attachments" folder. I can then query it using the REST API and find its id and other attributes. The test email is sent correctly.

2. I upload a similar attachment file to my "conversations attachments" folder using the REST API and checked that it appears in the folder and has identical attributes (e.g. mime_class, hidden, etc.) So both the attachment in 1, and the REST API uploaded attachment, are in the same "conversations attachments" folder and do not seem to have any obvious differences between them. 

3. If I try to send an message using the API "Create a conversation", it works fine with no attachment, but with using either the attachment id of the attachment created in 1, or using  2 as explained above, the email does not get sent and I get a response 500 error and the email is not sent. The body of the POST that I send has as its body:

body=This+is+a+test+of+the+email+system.+Please+ignore.&recipients=3204641&subject=This+is+a+test.+Ignore.&group_conversation=False&attachment_ids=58928187&mode=sync

Any help trying to understand what I'm doing wrong would be greatly appreciated!

Josh

[stuart_ryan]

Hi  @josh3 ,

That is a conundrum to be sure! I have had a look at the API, and, from what you are mentioning it certainly seems as though this should work.

Would it be possible for you to share the code/specific calls that you are making, and also let us know the tool you are using to make the API calls. Having your specific examples can help diagnose, as well as helps so we can rapidly attempt the same thing you are.

Look forward to hearing from you!

Cheers,
Stuart

[josh3]

Hi Stuart,

Thanks for your rapid response!. I simplified the code to demonstrate the

error. I'm using the canvas python sdk

<https://github.com/penzance/canvas_python_sdk/blob/master/canvas_sdk/methods/conversations.py>

and the function conversations.create_conversation(). If you actually

wanted to run it, you'd have to provide a valid attachment_id and user id.

The message I sent before showed the body of the http request I got by

drilling down into the POST that this function actually creates. For what

it's worth, it looks reasonable to me. I've used the python sdk a lot and

it seems in general to work fine. I also attach a screenshot showing that

this attachment id is indeed correct. I have chrome running with the

javascript console and have put in an canvas api request to list the files

in my conversation attachments folder.

Please let me know if there's anything else that you'd need.

Cheers,

Josh

On Sat, Dec 9, 2017 at 5:39 PM, stuart.ryan@uts.edu.au <

[stuart_ryan]

Hi  @josh3 ,

Thanks for that info, while I have a play around with this, have you tried the same call directly via the Canvas Live API? You can get more info on this here Canvas Live API .

I would be curious to see if the same call directly through the live API works or returns the same 500 error. That would help narrow down if it is an issue with the data/API or possibly the Python Canvas SDK.

Let me know how you go and I will also keep you posted!

Cheers,
Stuart

[josh3]

Hi Stuart,

I tried the Canvas Live API, and it doesn't work either, but I think for

some other reasons. It doesn't work there even without an attachment id,

and I'm using the identical access token as I was using previously. That

token seems operational since other queries seem to work.

But I did try directly using the JavaScript Developer Console on chrome,

and got exactly the say 500 response error as when going through the canvas

python sdk. And it also succeeds when sending without an attachment. So

this does narrow it down a bit as it shows it is nothing to do with the

api, and seems to have something to do with including an attachment id. I

also tried changing the recipient, and it is the same error even when I

make the recipient myself. Here's the query I used that worked (no

attachment_id)

$.post("/api/v1/conversations?body=testoftheemailsystem.Pleaseignore.&recipients=1586543&subject=Thisisatest.Ignore.&group_conversation=False&mode=sync",

function(data) { console.log(data); },'json');

and this is one that failed:

$.post("/api/v1/conversations?body=testoftheemailsystem.Pleaseignore.&recipients=1586543&subject=Thisisatest.Ignore.&group_conversation=False&attachment_ids=58928187&mode=sync",

function(data) { console.log(data); },'json');

with the response:

jquery.js:8240 POST

https://cole2.uconline.edu/api/v1/conversations?body=testoftheemailsystem.Pleaseignore.&recipients=1586543&subject=Thisisatest.Ignore.&group_conversation=False&attachment_ids=58928187&mode=sync

500 (Internal Server Error)

and the response text: "{"errors":[{"message":"An error

occurred.","error_code":"internal_server_error"}],"error_report_id":"99293251"}

"

I guess the question is, has anyone else successfully included an

attachment this way through the REST API? If so, I guess I should check if

other users with our same Canvas instance, that we're using at the

University of California, have the same problem. I've been successfully

using the REST API to do all sorts of things involving downloading student

data, and uploading pages, and haven't encountered a problem like this

before.

Cheers,

Josh

On Sun, Dec 10, 2017 at 1:53 AM, stuart.ryan@uts.edu.au <

[josh3]

Hi Stuart,

I forgot to mention that the response I got when I tried to create a

conversation using the live api was "Status": "422 Unprocessable Entity". I

tried changing the recipient user id's and various other things to no

avail. But as I said, this seems to be a different issue.

Best,

Josh

[stuart_ryan]

Hi Josh,

As Peter has suggested, contacting support may be the best option. One thing I noted in your previous response was:

and the response text: "{"errors":[{"message":"An error

occurred.","error_code":"internal_server_error"}],"error_report_id":"99293251"}

When you contact Canvas Support, ask them for the first line of the error report with that ID. When we have had issues with the API in the past, the first line of that error report gave incredibly valuable information about what was going wrong (and at least, in our case, pointed us to better understanding of how to use the API and resolve the issue).

It definitely seems like something else might be astray here, so good to raise it with support none-theless, however the first line of the error report may reveal some additional details about what is going wrong that could be helpful to resolve the issue more quickly.

Look forward to hearing how you go.

Stuart

[pklove]

Hi Josh,

I get the same error if I try using curl.  Fine with no attachment, internal server error if I include one.

That's not much help in solving the problem, but I think it confirms there is some issue rather than some problem specific to you.

Peter

[josh3]

Thanks Peter!

That indeed was very helpful. Do you think that there's any chance of this

getting fixed before the middle of January? If not, I'll find some hack to

get around this issue.

By the way, I'll be on a plane in San Francisco in a few hours, flying off

to Nelson, which is in your neck of the woods!

Cheers!

Josh

[pklove]

I guess to get it investigated/fixed, you'll need to contact Canvas support.

Enjoy Nelson.

[josh3]

Thanks again, I'll try to do that. Nelson is awesome!

Josh

[josh3 · Accepted solution]

I did contact Canvas support and they gave me the solution. It involves changing the raw http POST. If you modify the chrome javascript console query above:

$.post("/api/v1/conversations?body=testoftheemailsystem.Pleaseignore.&recipients=1586543&subject=Thisisatest.Ignore.&group_conversation=False&attachment_ids=58928187&mode=sync",

function(data) { console.log(data); },'json');

to

$.post("/api/v1/conversations?body=testoftheemailsystem.Pleaseignore.&recipients=1586543&subject=Thisisatest.Ignore.&group_conversation=False&attachment_ids[]=58928187&mode=sync",

function(data) { console.log(data); },'json');

Note the extra "[]" that is added after attachment_ids. This is another way of sending posts of array-like data. This fixes the bug and it works.

The standard python library that was getting invoked by the Canvas Python SDK ,  was "requests". It made this query string without the "[]" as presumably that normally works fine with the Canvas REST API. However for this particular function, it doesn't. Apparently from above, the same problem occurs with using curl. I was able to kludge this in the Canvas Python SDK by passing in optional kwargs. So all is good! Hopefully this problem will be addressed at some point by Canvas so this is no longer a problem.

Thanks for everyone's help!

Josh

[pklove]

Hi Josh,

Thanks for posting this.  Adding the [] works in curl as well.

This is inconsistent with other API calls where you can drop the [] for a single item.  But I might have only ever done this on GETs, I wonder if other POSTs are the same, so maybe it isn't inconsistent.

Apart from testing with curl, I use JSON in applications, so this issue does't show up there.

Peter

[stuart_ryan]

Hi Josh,

Thanks so much for coming back with the solution. Glad the Canvas Support team was able to able narrow down the issue and get you working.

Also, greatly appreciate you coming back to share this in detail as it will likely help others that run into the same issue in future!

Cheers,

Stuart