public void NewInstanceUsesCurrentTimeAsCustomEpoch()
{
var epoch = DateTimeOffset.UtcNow.ToUnixTimeMilliseconds();
var generator = new DistributedUIDGenerator();
// Allow for a 1 millisecond diff in case we ticked over during the test.
var diff = generator.CustomEpoch - epoch;
Assert.LessOrEqual(diff, 1, "Expected the custom epoch to be equal to the current Unix time now but it was not.");
}
public void DefaultMachineIdIsTheSame()
{
var machineId = new DistributedUIDGenerator().MachineId;
Assert.AreNotEqual(0, machineId, "Expected a valid machine id");
for (int i = 0; i < 10; ++i)
{
Assert.AreEqual(machineId, new DistributedUIDGenerator().MachineId, "Expected machine id to match but it did not");
}
}
public void MachineIdValuesAreClampedTo10bitRange()
{
const int kMachineIdBits = 10;
int MaxNodeId = (int)(Mathf.Pow(2, kMachineIdBits) - 1);
var generator = new DistributedUIDGenerator();
// Too large
generator.MachineId = MaxNodeId + 1;
Assert.AreEqual(MaxNodeId, generator.MachineId, $"Expected value to be clamped when it is greater than MaxNodeId({MaxNodeId})");
// Too small
generator.MachineId = -123;
Assert.AreEqual(1, generator.MachineId, "Expected value to be clamped when it is less than 1.");
// Just right
const int CorrectId = 321;
generator.MachineId = CorrectId;
Assert.AreEqual(CorrectId, generator.MachineId);
}
public void IdsAreUniqueForEachMachine()
{
HashSet <long> generatedIds = new HashSet <long>();
// Same time for all.
var epoch = DateTimeOffset.UtcNow.ToUnixTimeMilliseconds() - 1;
var machine1 = new DistributedUIDGenerator(epoch)
{
MachineId = 11
};
var machine2 = new DistributedUIDGenerator(epoch)
{
MachineId = 2312
};
var machine3 = new DistributedUIDGenerator(epoch)
{
MachineId = 33
};
for (int i = 0; i < kGeneratedIdCount; ++i)
{
var id1 = machine1.GetNextKey();
var id2 = machine2.GetNextKey();
var id3 = machine3.GetNextKey();
Assert.False(generatedIds.Contains(id1), $"Duplicate id. The id {id1} has already been generated.");
generatedIds.Add(id1);
Assert.False(generatedIds.Contains(id2), $"Duplicate id. The id {id2} has already been generated.");
generatedIds.Add(id2);
Assert.False(generatedIds.Contains(id3), $"Duplicate id. The id {id3} has already been generated.");
generatedIds.Add(id3);
}
}
