/// <summary>
/// Implements advice logic.
/// Usually, advice must invoke context.Proceed()
/// </summary>
/// <param name="context">The method advice context.</param>
/// <exception cref="System.InvalidOperationException"></exception>
public void Advise(MethodAdviceContext context)
{
var invokedMethod = (MethodInfo)context.TargetMethod;
var restCall = RestCall.FromMethod(invokedMethod);
if (restCall == null)
{
throw new NotImplementedException();
}
// first, replace the parameters
// (not elegant way)
var path = restCall.Path;
var parameters = invokedMethod.GetParameters();
for (int parameterIndex = 0; parameterIndex < parameters.Length; parameterIndex++)
{
var parameter = context.Parameters[parameterIndex];
var literalParameter = parameter != null?parameter.ToString() : "";
var literalParameterPlaceholder = "{" + parameters[parameterIndex].Name + "}";
path = path.Replace(literalParameterPlaceholder, literalParameter);
}
// then create the route and send the request
var hostAddress = _hostAddress;
if (hostAddress == null)
{
var serviceContractAttribute = context.TargetType.GetCustomAttribute <ServiceContractAttribute>();
hostAddress = new Uri(serviceContractAttribute.Namespace);
}
var target = DnsNameResolver.LocalResolve(hostAddress.Host);
using (var stream = _route.Connect(target, hostAddress.Port).ToNetworkStream())
{
var request = new HttpRequest(restCall.Verb, path)
.AddHeader("Host", hostAddress.GetHostAndPort())
.AddHeader("Connection", "Close")
.AddHeader("Proxy-Connection", "Keep-Alive");
request.Write(stream);
var response = HttpResponse.FromStream(stream);
if (response.StatusCode >= 400)
{
var errorText = response.ReadContentString(stream);
throw new InvalidOperationException(errorText);
}
// handle return value
if (invokedMethod.ReturnType != typeof(void))
{
var contentString = response.ReadContentString(stream);
using (var contentStream = new MemoryStream(Encoding.UTF8.GetBytes(contentString)))
{
var serializer = new DataContractJsonSerializer(invokedMethod.ReturnType);
var result = serializer.ReadObject(contentStream);
context.ReturnValue = result;
}
}
}
}
public ResolverForm()
{
InitializeComponent();
_nameResolver = new DnsNameResolver();
}
