/// <summary>
/// Constructs a new <see cref="RedirectHandler"/>
/// </summary>
/// <param name="innerHandler">An HTTP message handler to pass to the <see cref="HttpMessageHandler"/> for sending requests.</param>
/// <param name="redirectOption">An OPTIONAL <see cref="Microsoft.Graph.RedirectHandlerOption"/> to configure <see cref="RedirectHandler"/></param>
public RedirectHandler(HttpMessageHandler innerHandler, RedirectHandlerOption redirectOption = null)
: this(redirectOption)
{
InnerHandler = innerHandler;
}
/// <summary>
/// Sends the Request
/// </summary>
/// <param name="request">The <see cref="HttpRequestMessage"/> to send.</param>
/// <param name="cancellationToken">The <see cref="CancellationToken"/>for the request.</param>
/// <returns>The <see cref="HttpResponseMessage"/>.</returns>
protected override async Task <HttpResponseMessage> SendAsync(HttpRequestMessage request, CancellationToken cancellationToken)
{
RedirectOption = request.GetMiddlewareOption <RedirectHandlerOption>() ?? RedirectOption;
// send request first time to get response
var response = await base.SendAsync(request, cancellationToken);
// check response status code and redirect handler option
if (IsRedirect(response.StatusCode) && RedirectOption.ShouldRedirect(response) && RedirectOption.MaxRedirect > 0)
{
if (response.Headers.Location == null)
{
throw new ServiceException(
new Error
{
Code = ErrorConstants.Codes.GeneralException,
Message = ErrorConstants.Messages.LocationHeaderNotSetOnRedirect,
},
response.Headers,
response.StatusCode);
}
var redirectCount = 0;
while (redirectCount < RedirectOption.MaxRedirect)
{
// Drain response content to free responses.
if (response.Content != null)
{
await response.Content.ReadAsByteArrayAsync();
}
// general clone request with internal CloneAsync (see CloneAsync for details) extension method
var newRequest = await response.RequestMessage.CloneAsync();
// status code == 303: change request method from post to get and content to be null
if (response.StatusCode == HttpStatusCode.SeeOther)
{
newRequest.Content = null;
newRequest.Method = HttpMethod.Get;
}
// Set newRequestUri from response
if (response.Headers.Location.IsAbsoluteUri)
{
newRequest.RequestUri = response.Headers.Location;
}
else
{
var baseAddress = newRequest.RequestUri.GetComponents(
UriComponents.SchemeAndServer | UriComponents.KeepDelimiter, UriFormat.Unescaped);
newRequest.RequestUri = new Uri(baseAddress + response.Headers.Location);
}
// Remove Auth if http request's scheme or host changes
if (String.CompareOrdinal(newRequest.RequestUri.Host, request.RequestUri.Host) != 0 ||
String.CompareOrdinal(newRequest.RequestUri.Scheme, request.RequestUri.Scheme) != 0)
{
newRequest.Headers.Authorization = null;
}
// Send redirect request to get reponse
response = await base.SendAsync(newRequest, cancellationToken);
// Check response status code
if (!IsRedirect(response.StatusCode))
{
return(response);
}
redirectCount++;
}
throw new ServiceException(
new Error
{
Code = ErrorConstants.Codes.TooManyRedirects,
Message = string.Format(ErrorConstants.Messages.TooManyRedirectsFormatString, redirectCount)
});
}
return(response);
}
/// <summary>
/// Constructs a new <see cref="RedirectHandler"/>
/// </summary>
/// <param name="redirectOption">An OPTIONAL <see cref="Microsoft.Graph.RedirectHandlerOption"/> to configure <see cref="RedirectHandler"/></param>
public RedirectHandler(RedirectHandlerOption redirectOption = null)
{
RedirectOption = redirectOption ?? new RedirectHandlerOption();
}