public async Task <string> ValidateCredentialAsync(CancellationToken cancellationToken)
{
var tokenHttpClient = new VssOAuthTokenHttpClient(this.SignInUrl);
var tokenResponse = await tokenHttpClient.GetTokenAsync(this.Grant, this.ClientCredential, this.TokenParameters, cancellationToken);
// return the underlying authentication error
return(tokenResponse.Error);
}
/// <summary>
/// Issues a token request to the configured secure token service. On success, the access token issued by the
/// token service is returned to the caller
/// </summary>
/// <param name="failedToken">If applicable, the previous token which is now considered invalid</param>
/// <param name="cancellationToken">A token used for signalling cancellation</param>
/// <returns>A <c>Task&lgt;IssuedToken></c> for tracking the progress of the token request</returns>
protected override async Task <IssuedToken> OnGetTokenAsync(
IssuedToken failedToken,
CancellationToken cancellationToken)
{
if (this.SignInUrl == null ||
this.Grant == null ||
this.ClientCredential == null)
{
return(null);
}
IssuedToken issuedToken = null;
var traceActivity = VssTraceActivity.Current;
try
{
var tokenHttpClient = new VssOAuthTokenHttpClient(this.SignInUrl);
var tokenResponse = await tokenHttpClient.GetTokenAsync(this.Grant, this.ClientCredential, this.TokenParameters, cancellationToken).ConfigureAwait(false);
if (!String.IsNullOrEmpty(tokenResponse.AccessToken))
{
// Construct a new access token based on the response, including the expiration time so we know
// when to refresh the token.
issuedToken = CreateIssuedToken(tokenResponse);
if (!String.IsNullOrEmpty(tokenResponse.RefreshToken))
{
// TODO: How should this flow be handled? Refresh Token is a credential change which is not
// the same thing as access token storage
}
}
else if (!String.IsNullOrEmpty(tokenResponse.Error))
{
// Raise a new exception describing the underlying authentication error
throw new VssOAuthTokenRequestException(tokenResponse.ErrorDescription)
{
Error = tokenResponse.Error,
};
}
else
{
// If the error property isn't set, but we didn't get an access token, then it's not
// clear what the issue is. In this case just trace the response and fall through with
// a null access token return value.
var sb = new StringBuilder();
var serializer = JsonSerializer.Create(s_traceSettings.Value);
using (var sr = new StringWriter(sb))
{
serializer.Serialize(sr, tokenResponse);
}
VssHttpEventSource.Log.AuthenticationError(traceActivity, this, sb.ToString());
}
}
catch (VssServiceResponseException ex)
{
VssHttpEventSource.Log.AuthenticationError(traceActivity, this, ex);
}
return(issuedToken);
}
