protected override async Task <HttpResponseMessage> SendAsync(HttpRequestMessage request, CancellationToken cancellationToken)
{
_ = request ?? throw new ArgumentNullException(nameof(request));
var httpRequestHeaders = request.Headers;
// If you have the following attribute in your interface, the authorization header will be "Bearer", not null.
// [Headers("Authorization: Bearer")]
// If we have a token, then we want to use that token - otherwise generate a service to service one.
var authenticationHeaderValue = httpRequestHeaders.Authorization;
if (authenticationHeaderValue != null)
{
if (authenticationHeaderValue.Scheme == "Bearer" && !string.IsNullOrWhiteSpace(authenticationHeaderValue.Parameter))
{
var scopes = new List <string>()
{
"https://graph.microsoft.com/User.Read"
};
var accessToken = await tokenCreator.GetAccessTokenOnBehalfOf(scopes, authenticationHeaderValue.Parameter);
httpRequestHeaders.Authorization = new AuthenticationHeaderValue(authenticationHeaderValue.Scheme, accessToken);
}
else
{
if (!string.IsNullOrWhiteSpace(tokenCreatorConfiguration.TestUsername) && !string.IsNullOrWhiteSpace(tokenCreatorConfiguration.TestPassword))
{
var accessToken = await tokenCreator.GetIntegrationTestTokenAsync();
httpRequestHeaders.Authorization = new AuthenticationHeaderValue(authenticationHeaderValue.Scheme, accessToken);
}
else
{
var accessToken = await tokenCreator.GetClientApplicationAccessTokenAsync();
httpRequestHeaders.Authorization = new AuthenticationHeaderValue(authenticationHeaderValue.Scheme, accessToken);
}
}
}
return(await base.SendAsync(request, cancellationToken));
}
private GraphServiceClient BuildGraphServiceClient(AuthenticationHeaderValue authenticationHeaderValue)
{
_ = authenticationHeaderValue ?? throw new ArgumentNullException(nameof(authenticationHeaderValue));
var delegateAuthenticationProvider = new DelegateAuthenticationProvider(
async(requestMessage) =>
{
var scopes = new List <string>()
{
"https://graph.microsoft.com/User.Read", "https://graph.microsoft.com/OnlineMeetings.ReadWrite"
};
var userToken = await tokenCreator.GetAccessTokenOnBehalfOf(scopes, authenticationHeaderValue.Parameter);
// Append the access token to the request.
requestMessage.Headers.Authorization = new AuthenticationHeaderValue("bearer", userToken);
});
var graphServiceClient = new GraphServiceClient(delegateAuthenticationProvider);
return(graphServiceClient);
}