Teams Tab API access to Sharepoint FIle Contents causing 405 on OPTIONS call

Question

In Microsoft Teams, I have crated an App that lists files of a certain type in a Tab
The use case is that the contents of the file need to be read by my Javascript
the Javascript in the Tab already successfully gets an ID Token and Access Token (via ADAL)
this code already successfully lists the DriveItems in the group the current logged in user can see via https://graph.microsoft.com/v1.0/groups/${groupId}/drive/root/search(q='{pdf}');`
when I attempt to GET the DriveItem via https://graph.microsoft.com/v1.0/groups/${groupId}/drive/items/${itemId}/content
- where the itemId is returned from the first call
- I successfully see the HTTP 302 from the https://graph.microsoft.com endpoint redirecting to https://<thesharepointsite>.sharepoint.com/<etc>
Axios (and the Microsoft Graph Javascript API) are successfully traversing to the redirect
Postman, with the same https://graph... URL with the AccessToken successfully downloads the binary content from the 302 redirect (so it is not an Auth issue)

PROBLEM

in Microsoft Teams, inside my Tab, the browser (built inside of the Teams desktop app) HTTP calls to https://<thesharepointside>.sharepoint.com respond with a 405 error on the OPTIONS call
usually this means there is a CORS issue, and so the solution is to add the domain to the validDomains of the app

Attempted Solution

"validDomains": [
       ...

        "*.sharepoint.com",
        "graph.microsoft.com",
        "login.microsoftonline.com"
    ]

manually add the full domain the the Teams App's Manifest
use the suggested "{teamsitedomain}" as per https://learn.microsoft.com/en-us/microsoftteams/platform/resources/schema/manifest-schema#validdomains
*.sharepoint.com as per above
use the Microsoft Graph Javascript APIs

In all instances, I get 405 on the OPTIONS call

No file download from within the Tab within Microsoft Teams.

Suggestions?

score 1 · Answer 1 · answered Nov 04 '19 at 09:29

THIS MAY answer your question in the future

my code now does a https://graph.microsoft.com/v1.0/groups/${groupId}/drive/items/${itemId}
this is an Instance of DriveItem and returns a property on the JSON response: @microsoft.graph.downloadUrl
as per Microsoft Graph API Download File content return Unauthorized 401 this is a short-lived URL you can traverse without Auth headers
the content of my file was returned successfully (no CORS issue)
I can now download the contents of the DriveItem within a Tab
I hope this helps someone

1 Answers1