Rest API call return 0 items in list even there's data when using App deamon model

Question

In a list I have some items. I want to call Rest api to list these items.

When I call the api url from the browser, I get the expected result (items are returned).

When I call the api from Insomnia Rest client, I get no result. By no result I mean the result set is returned without error, but empty.

What I've done :

• in AAD portal, I registered a new application, a client ID and an App Secret.
• I autorize (admin consent) :
  • Microsoft Graph : Sites.Read.All and Sites.ReadWrite.All
  • SharePoint : Sites.FullControl.All, Sites.Manage.All, Sites.Read.All and Sites.ReadWrite.All
• in insomnia, I set up OAuth 2.0 authentication :
  • Grant type : Authorization Code
  • Authorization Url : https://login.microsoftonline.com/common/oauth2/authorize?resource=https://mytenant.sharepoint.com
  • Access token Url: https://login.microsoftonline.com/common/oauth2/token
  • Client ID: my generated client ID
  • Client secret : my generated secret
  • Redirect URL : https://login.microsoftonline.com/common/oauth2/nativeclient
  • Header : only Accept=application/json;odata=verbose because authentication headers are handled by insomnia.

The url I target is https://mytenant.sharepoint.com/sites/mysitecoll/_api/Web/Lists(guid'b6e9527d-a902-4b15-b77b-d49e701fdd92')/items.

The result of this call is (status 200 OK):

{
  "d": {
    "results": []
  }
}

As you can see there's no error, but no data.

What's puzzling me is that calling : https://mytenant.sharepoint.com/sites/mysitecoll/_api/Web/Lists(guid%27b6e9527d-a902-4b15-b77b-d49e701fdd92%27)?%24select=ItemCount actually returns :

{
  "d": {
    "__metadata": {
      ....
    },
    "ItemCount": 3
  }
}

There is data.

What's missing ?

As a side note, using the Graph, everything is ok : https://graph.microsoft.com/v1.0/sites/mytenant.sharepoint.com,b969074a-6a95-4235-a520-17893eca8fbe,4d32dad1-6bcc-4b57-becc-7e476c851046/lists/b6e9527d-a902-4b15-b77b-d49e701fdd92/items returns expected data

Answer 1

It's a problem with permissions..

For test just try to add permissions to specific list/library

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

And choose list/library in a step after you press create..

Answer 2

I had the same issue. Later I found I made a mistake on the below Scope attribute value. I was putting my List URL below but it is actually a static text

Scope="http://sharepoint/content/sitecollection/web/list"