public async Task Lookup_RetryOnDnsErrorAsync()
{
var lookup = new LookupClient(
new NameServer(IPAddress.Parse("127.0.0.1")),
new NameServer(IPAddress.Parse("127.0.0.2")),
new NameServer(IPAddress.Parse("127.0.0.3")),
new NameServer(IPAddress.Parse("127.0.0.4")),
new NameServer(IPAddress.Parse("127.0.0.5")),
new NameServer(IPAddress.Parse("127.0.0.6")),
new NameServer(IPAddress.Parse("127.0.0.7")))
{
EnableAuditTrail = true,
ContinueOnDnsError = true
};
var calledIps = new List <IPAddress>();
var messageHandler = new TestMessageHandler((ip, req) =>
{
calledIps.Add(ip.Address);
return(new DnsResponseMessage(
new DnsResponseHeader(1, (int)DnsResponseCode.NotExistentDomain, 0, 0, 0, 0),
0));
});
var request = new DnsRequestMessage(
new DnsRequestHeader(0, DnsOpCode.Query),
new DnsQuestion("test.com", QueryType.A, QueryClass.IN));
var result = await lookup.ResolveQueryAsync(lookup.GetNextServers(), messageHandler, request, false);
// no exception but error in the response after calling all 3 endpoints!
Assert.True(result.HasError);
Assert.Equal(DnsResponseCode.NotExistentDomain, result.Header.ResponseCode);
// ensure the client tried all the configured endpoints
Assert.Equal(7, calledIps.Count);
}
public void Lookup_PreserveNameServerOrder()
{
var lookup = new LookupClient(
new NameServer(IPAddress.Parse("127.0.0.1")),
new NameServer(IPAddress.Parse("127.0.0.2")),
new NameServer(IPAddress.Parse("127.0.0.3")))
{
// default is true
UseRandomNameServer = false
};
var calledIps = new List <IPAddress>();
var messageHandler = new TestMessageHandler((ip, req) =>
{
calledIps.Add(ip.Address);
return(new DnsResponseMessage(
new DnsResponseHeader(1, (int)DnsResponseCode.NoError, 0, 0, 0, 0),
0));
});
// calling multiple times will always use the first server when it returns NoError.
// No other servers should be called
for (var i = 0; i < 3; i++)
{
var request = new DnsRequestMessage(
new DnsRequestHeader(i, DnsOpCode.Query),
new DnsQuestion("test.com", QueryType.A, QueryClass.IN));
var result = lookup.ResolveQuery(lookup.GetNextServers(), messageHandler, request, false);
Assert.False(result.HasError);
}
Assert.Equal(3, calledIps.Count);
Assert.Equal(IPAddress.Parse("127.0.0.1"), calledIps[0]);
Assert.Equal(IPAddress.Parse("127.0.0.1"), calledIps[1]);
Assert.Equal(IPAddress.Parse("127.0.0.1"), calledIps[2]);
}
/// <summary>
/// 通过数据转换
/// </summary>
/// <param name="message"></param>
/// <returns></returns>
public DnsClientRequest FromArray(byte[] message)
{
DnsRequestMessage request = DnsRequestMessage.FromArray(message);
return(new DnsClientRequest(_coder, request));
}
public DnsResponseMessage Resolve(IPEndPoint server, string domainNameToResolve)
{
DnsRequestMessage request = messageProcessor.ProcessRequest(domainNameToResolve);
return(Resolve(server, request));
}
public override Task <DnsResponseMessage> QueryAsync(IPEndPoint endpoint, DnsRequestMessage request, CancellationToken cancellationToken, Action <Action> cancelationCallback)
{
return(Task.FromResult(_onQuery(endpoint, request)));
}
public override DnsResponseMessage Query(IPEndPoint endpoint, DnsRequestMessage request, TimeSpan timeout)
{
return(_onQuery(endpoint, request));
}
