I'm currently building a .NET Core App which performs direct SharePoint REST calls to: contoso.sharepoint.com/sites/shipment/_api/search/query?querytext='...'

The .NET Core App is registerd in the Application Registrations. How do I retrieve the Access Token? (For some reason MS Graph API is not able to make these calls, hence trying SPO REST API)

CodePudding user response：

You could use the certificate way to get the token like this:

    private static async Task<string> GetToken()
    {
        string applicationId = "xxx";
        string tenantId = "contoso.onmicrosoft.com";
        X509Certificate2 certificate = new X509Certificate2(@"C:\certificate.pfx", "password");

        IConfidentialClientApplication confApp = ConfidentialClientApplicationBuilder.Create(applicationId)
        .WithAuthority($"https://login.microsoftonline.com/{tenantId}")
        .WithCertificate(certificate) // This is just a local method that gets the certificate on my machine
        .Build();

        var scopes = new[] { "https://contoso.sharepoint.com/.default" };
        var authenticationResult = await confApp.AcquireTokenForClient(scopes).ExecuteAsync();
        return authenticationResult.AccessToken;
    }

CodePudding user response：

I'm using the following code for public client application

public async Task<string> GetTokenAsync()
{
    var clientId = "{client_id}";
    var tenantId = "{tenant_id}";
    var instance = "https://login.microsoftonline.com";
    IPublicClientApplication clientApp = PublicClientApplicationBuilder.Create(clientId)
                .WithAuthority($"{instance}/{tenantId}")
                .WithDefaultRedirectUri()
                .Build();

    var accounts = await clientApp.GetAccountsAsync();
    var firstAccount = accounts.FirstOrDefault();

    var scopes = new[] { "https://contoso.sharepoint.com/.default" };
    var userName = "{user}";
    SecureString password = ...;
    AuthenticationResult authResult;
    try
    {
        authResult = await clientApp.AcquireTokenSilent(scopes, firstAccount).ExecuteAsync();
    }
    catch (MsalUiRequiredException ex)
    {
        authResult = await clientApp
                    .AcquireTokenByUsernamePassword(scopes, userName, password)
                    .ExecuteAsync();
    }
    return authResult.AccessToken;
}