SharePoint Online Rest API (Add ListItem)

[Milind Saraswala]

I have issue with Adding List Item But I can Read List Item without any issue. I will narrate full step how I did. I want to use REST API outside SharePoint Online.

1. I register App by going to https://xxxx.sharepoint.com/_layouts/15/appregnew.aspx on SharePoint Online.
2. When I register I mention my client id, client secret, app domain and redirect uri
3. Once I did I find my site realm by navigating to https://xxxx.sharepoint.com/_vti_bin/client.svc
4. Now I navigate to https://xxxx.sharepoint.com/_layouts/15/OAuthAuthorize.aspx?client_id=my_client_id&scope=app_permissions_list&response_type=code&redirect_uri=redirect_uri
5. I pass client id and redirect uri which I mention when I register App and mention scope as List.Read List.Write, So I got code which expire after 5 minutes
6. From that code I navigate to https://accounts.accesscontrol.windows.net/site_realm/tokens/OAuth/2 where I pass in body
   • grant_type = authorization_code
   • client_id = client id @ site_realm
   • client_secrete = client secrete
   • redirect_uri = redirect url
   • resource = audience principal ID/ my sharepoint domain @ site_realm
7. And I got access token and refresh token. Where access token remain for 12 hours and after that you can do point 6 with refresh_token 

After that I run below code to get Custom List items

$.ajax({
        url: "https://xxxx.sharepoint.com/_api/lists/getbytitle('Feedback')/items?$select=Title,URL",
        method: 'GET',
        headers: {
          "Accept": "application/json; odata=verbose",
          "Authorization": "Bearer " + accessToken,
        }
      })

This works without issue, but when I try to add list item I get error Access denied. You do not have permission to perform this action or access this resource

$.ajax({
        url: "https://xxxx.sharepoint.com/_api/lists/getbytitle('Feedback')/items",
        method: "POST",
        contentType: "application/json;odata=verbose",
        data: JSON.stringify(data),
        headers: {
          "Authorization": "Bearer " + accessToken,
          "Accept": "application/json; odata=verbose",
          "Content-Type": "application/json",
        },
        success: function (data) {
          alert('Item added successfully');
        },
        error: function (error) {
          alert("Error: " + JSON.stringify(error));
        }
      })

Please help to resolve the issue of access denied and let me know what I am missing

[#2]

You may check if your account has written permission. Go to Site Settings-->People & Group.

[#3]

I am System Administrator of Office 365, So I have Full Access to the SharePoint Online

[#4 · Accepted solution]

@Milind Saraswala if you are using the add-in model for authentication, you probably need to define the permissions that the app need when you register at https://xxxx.sharepoint.com/_layouts/15/appregnew.aspx

After you register the app, go to /_layouts/15/appinv.aspx and use the App Id from the registration to Lookup the details. When they load, add the required permissions on the Permission Request XML field.

For your case, I suspect it will look similar to:

<AppPermissionRequests>

<AppPermissionRequest Scope="http://sharepoint/content/sitecollection/web/list" Right="Write"/> </AppPermissionRequests>

You can find additional information here:

https://docs.microsoft.com/en-us/sharepoint/dev/sp-add-ins/add-in-permissions-in-sharepoint

Hope this helps

[#5]

Is this working now for you.  We are looking for a similar API setup, so wanted to check if this worked for you.

[#6]

Yes it is working :) 

[#7]

Thank you.