public async Task TestQuery()
{
using var tokenSource = new CancellationTokenSource(TimeSpan.FromMilliseconds(500));
var endpoint = GenerateEndPoint();
// Create a real upstream DNS client to serve the request (todo: mock this)
using var upstream = new DnsUdpClient(IPAddress.Parse("1.1.1.1"));
// Create a loopback server
using var server = new DnsUdpServer(endpoint, upstream);
// Start recieving
using var receiveTask = server.Listen(tokenSource.Token);
// Create a loopback DNS client to talk to the server
using var client = new DnsUdpClient(endpoint);
try
{
var query = DnsQueryFactory.CreateQuery("google.com");
// Send a DNS request to the server, verify the results
var response = await client.Query(query, tokenSource.Token);
Assert.Equal(query.Id, response.Header.Id);
Assert.Equal(query.Host, response.Header.Host);
Assert.True(response.Answers.Count > 0);
}
finally
{
tokenSource.Cancel();
await receiveTask;
}
}
public async Task TestLookupTimeout()
{
// Reserved - see https://en.wikipedia.org/wiki/Reserved_IP_addresses
using var client = new DnsUdpClient(new NullLogger <DnsUdpClient>(), IPAddress.Parse("192.88.99.0"));
await Assert.ThrowsAsync <DnsClientTimeoutException>(() => client.Query(DnsQueryFactory.CreateQuery("alanedwardes.com"), CancellationToken.None));
}