/// <summary>
/// Create delegating handler
/// </summary>
/// <param name="next"></param>
/// <param name="resourceId"></param>
/// <param name="handlers"></param>
/// <param name="proxy"></param>
/// <param name="logger"></param>
public HttpHandlerDelegate(HttpMessageHandler next, string resourceId,
IEnumerable <IHttpHandler> handlers,
IWebProxy proxy, ILogger logger) : base(next)
{
_resourceId = resourceId;
_logger = logger ?? throw new ArgumentNullException(nameof(logger));
var root = next.GetRoot();
if (root == null)
{
_logger.Error("Cannot configure root handler, inner " +
"most handler is not a configurable client handler");
return;
}
if (proxy != null)
{
if (root.SupportsProxy)
{
root.UseProxy = true;
root.Proxy = proxy;
}
else
{
_logger.Warning("Proxy configuration provided, but " +
"underlying handler does not support proxy " +
"configuration. Skipping proxy.");
}
}
if (handlers == null)
{
handlers = Enumerable.Empty <IHttpHandler>();
}
// Register validators
var validators = handlers
.OfType <IHttpCertificateValidator>()
.Cast <IHttpCertificateValidator>()
.ToList();
if (validators.Any())
{
validators.ForEach(h => h.Configure(this));
root.ServerCertificateCustomValidationCallback =
(req, cert, chain, err) => validators.All(
v => v.Validate(req.Headers, cert, chain, err));
}
// Save message handlers
_handlers = handlers
.OfType <IHttpMessageHandler>()
.Cast <IHttpMessageHandler>()
.OrderBy(h => h.Order)
.ToList();
_handlers.ForEach(h => h.Configure(this));
}