Missing programmatic endpoint for a team's root site

[Admiral-Skye]

Describe the bug

I am trying to find the root site for my teams group however it is not possible to get the root site from the graph sdk.

I am able to make the following http request in the graph explorer:
https://graph.microsoft.com/v1.0/groups/{group-id}/sites/root

However there is no corresponding request in the C# sdk under Graph.Groups[group.Id].Sites, this is also missing from the MSDN article which when looking at examples in C# and other languages suggest to use Graph.Groups[group.Id].Sites[site.id] which is only possible if the root site's id is known ahead of time.

Attempting the following code which does compile:

var site = Graph.Groups[group.Id].Sites["root"].GetAsync().Result

results in an exception: "Invalid object identifier 'sites'"

Expected behavior

A method to request the root site for a group exists.

Graph.Groups[group.Id].Sites.Root

How to reproduce

using the SDK to try and retrieve the root site of a group will show that it is functionally impossible without knowing the site's id ahead of time.

SDK Version

5.56.0

Latest version known to work for scenario above?

No response

Known Workarounds

No response

Debug output

Click to expand log

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### Configuration

- Windows x86

### Other information

_No response_

[andrueastman]

Thanks for raising this @Admiral-Skye

Any chance you can confirm if the url is as expected when running the code below?

            var requestInformation = graphClient.Groups[group.Id].Sites["root"].ToGetRequestInformation();
            Console.WriteLine(requestInformation.URI.OriginalString);

Do you still get the error once you paste and make the request using the Graph Explorer?

[Admiral-Skye]

Oh thanks @andrueastman! I see where I was going wrong, the request info helped me find the issue, apparently my group query was not including the id in its response which was causing an invalid request to be generated.

Correcting that issue further upstream means that

var site = Graph.Groups[group.Id].Sites["root"].GetAsync().Result;

works as expected.

I still think an explicit .Root would be welcome as other graph sdk calls for things like DriveItems include it explicitly

var rootDriveItem = Graph.Drives[drive.Id].Root.GetAsync().Result;

[andrueastman]

Thanks for confirming this @Admiral-Skye

At the moment, we won't be adding this due to related path expansion limitations documented at https://github.com/microsoftgraph/msgraph-sdk-dotnet/blob/dev/docs/upgrade-to-v5.md#drive-item-paths. As this is working, we'll close this issue for now.