public async Task Pruning()
{
var now = DateTime.Now;
var cache = new CachedNameServer {
Catalog = new Catalog(), AnswerAllQuestions = true
};
cache.Catalog.Add(new ARecord {
Name = "a.foo.org", Address = IPAddress.Loopback, TTL = TimeSpan.FromSeconds(30)
});
cache.Catalog.Add(new ARecord {
Name = "b.foo.org", Address = IPAddress.Loopback, TTL = TimeSpan.FromSeconds(60)
});
var query = new Message();
query.Questions.Add(new Question {
Name = "a.foo.org", Type = DnsType.A
});
query.Questions.Add(new Question {
Name = "b.foo.org", Type = DnsType.A
});
var response = await cache.ResolveAsync(query);
Assert.IsTrue(response.Answers.Any(a => a.Name == "a.foo.org"));
Assert.IsTrue(response.Answers.Any(a => a.Name == "b.foo.org"));
cache.Prune(now);
response = await cache.ResolveAsync(query);
Assert.IsTrue(response.Answers.Any(a => a.Name == "a.foo.org"));
Assert.IsTrue(response.Answers.Any(a => a.Name == "b.foo.org"));
cache.Prune(now + TimeSpan.FromSeconds(31));
response = await cache.ResolveAsync(query);
Assert.IsFalse(response.Answers.Any(a => a.Name == "a.foo.org"));
Assert.IsTrue(response.Answers.Any(a => a.Name == "b.foo.org"));
cache.Prune(now + TimeSpan.FromSeconds(61));
response = await cache.ResolveAsync(query);
Assert.IsFalse(response.Answers.Any(a => a.Name == "a.foo.org"));
Assert.IsFalse(response.Answers.Any(a => a.Name == "b.foo.org"));
}
public async Task AddingResponse_TTL0()
{
var now = DateTime.Now;
var cache = new CachedNameServer {
Catalog = new Catalog(), AnswerAllQuestions = true
};
var response = new Message
{
QR = true,
Answers = { new ARecord {
Name = "foo.org", Address = IPAddress.Loopback, TTL = TimeSpan.Zero
} },
AdditionalRecords = { new AAAARecord {
Name = "foo.org", Address = IPAddress.Loopback
} },
};
cache.Add(response);
var query = new Message
{
Questions =
{
new Question {
Name = "foo.org", Type = DnsType.A
},
new Question {
Name = "foo.org", Type = DnsType.AAAA
}
}
};
var res = await cache.ResolveAsync(query);
Assert.IsFalse(res.Answers.Any(a => a.Name == "foo.org" && a.Type == DnsType.A));
Assert.IsTrue(res.Answers.Any(a => a.Name == "foo.org" && a.Type == DnsType.AAAA));
}
public async Task Pruning_Background()
{
var cache = new CachedNameServer {
Catalog = new Catalog()
};
cache.Catalog.Add(new ARecord
{
TTL = TimeSpan.FromMilliseconds(500),
Name = "a.foo.org",
Address = IPAddress.Loopback
});
var query = new Message
{
Questions =
{
new Question {
Name = "a.foo.org", Type = DnsType.A
}
}
};
var res = await cache.ResolveAsync(query);
Assert.AreEqual(1, res.Answers.Count);
var cts = cache.PruneContinuously(TimeSpan.FromMilliseconds(200));
await Task.Delay(TimeSpan.FromSeconds(1));
cts.Cancel();
await Task.Delay(TimeSpan.FromMilliseconds(40));
res = await cache.ResolveAsync(query);
Assert.AreEqual(0, res.Answers.Count);
}