Retrieve siteId and listId from shared folder

Question

I am currently working on retrieving the siteId and listId from shared folders. So far I manage to do it on a Sharepoint folder where I have access to the Sharepoint root but when I use the URL of a shared Sharepoint location I am having the following error message: "Invalid hostname for the tenancy"

For a bit of context, my usecase is the following one:

A colleague of mine shares a folder with me from a Sharepoint (xxx.sharepoint.com).
I have access to his folder.
If I simply go to the root (xxx.sharepoint.com) I am having "access denied" which is fine (I believe).
I want to retrieve the sideId, listId (and eventually driveId) from the shared folder using the URL of this folder.

So far, as I said previously, I am able to retrieve those informations for a sharepoint folder where I do have access to the root. Unfortunatly, in my usecase previously describe I have an error and it is impossible to me to retrieve it even by retrieving all sites which I have access to or by getting the list from the folder URL.

The piece of code that I am using so far:

public async Task<List> UrlToList(string accessToken, string url)
{
    url = url.Replace("/Forms/AllItems.aspx", "");
    Uri uri = new Uri(url);
    var segments = string.Join("", uri.Segments[0..^1]).TrimEnd('/');

    var request = graphClient.Sites[uri.Host].SiteWithPath(segments).Lists.Request(Options(accessToken));
    var lists = await request.GetAsync();

    var list = lists.First(l => string.Compare(url, l.WebUrl, true) == 0);
    return list;
}

I only see two options so far... It could come from the configuration of xxx.sharepoint.com or a problem of permission.

Is there any possible way to retrieve those informations? If so, how? And is there also any code sample available somewhere?

Hub Hub · Accepted Answer · 2020-01-30T08:23:53

After experimenting different solution, the exact reason of this error due to a different tenancy between the user and the sharepoint destination.

To solve it you need first to do a HTTP Get request to the url xxx.sharepoint.com/site/subsite/Forms/AllItems.aspx with an empty bearer. From that you will find the tenantId of the sharepoint destination.

Once you have the tenantId you will need to request a new access token with this tenantId like the following sample.

public async Task<string> GetAccessToken(string clientId, string clientSecret, string scope, string refreshToken, string grantType = "refresh_token", string tenantId = "common")
{
    var request = new HttpRequestMessage(HttpMethod.Post, $"https://login.microsoftonline.com/{tenantId}/oauth2/v2.0/token");
    request.Content = new FormUrlEncodedContent(new Dictionary<string, string>() {
        {"client_id", clientId },
        {"scope", scope },
        {"refresh_token", refreshToken },
        {"grant_type", grantType },
        {"client_secret", clientSecret }
    });

    HttpResponseMessage response = await client.SendAsync(request);

    response.EnsureSuccessStatusCode();

    var result = await response.Content.ReadAsStringAsync();
    return result;
}

With this access token if you request the sideId, listId,... of the given sharepoint destination you will be able to retrieve them.

Hope it will help you with this answer.

Retrieve siteId and listId from shared folder

1 Answers