public void PartitionKeyAssignmentIsStable(string[] partitions)
{
var iterationCount = 25;
var key = "this-is-a-key-1";
var resolver = new PartitionResolver();
var expected = resolver.AssignForPartitionKey(key, partitions);
for (var index = 0; index < iterationCount; ++index)
{
Assert.That(resolver.AssignForPartitionKey(key, partitions), Is.EqualTo(expected), $"The assignment for iteration: [{ index }] was unstable.");
}
}
public void PartitionKeyAssignmentDistributesKeysToDifferentPartitions(string[] partitions)
{
using var cancellationSource = new CancellationTokenSource();
cancellationSource.CancelAfter(EventHubsTestEnvironment.Instance.TestExecutionTimeLimit);
var keyLength = 20;
var requiredAssignments = (int)Math.Floor(partitions.Length * 0.67);
var assignedHash = new HashSet <string>();
var resolver = new PartitionResolver();
// Create the random number generator using a constant seed; this is
// intended to allow for randomization but will also keep a consistent
// pattern each time the tests are run.
var rng = new Random(412);
for (var index = 0; index < int.MaxValue; ++index)
{
var keyBuilder = new StringBuilder(keyLength);
for (var charIndex = 0; charIndex < keyLength; ++charIndex)
{
keyBuilder.Append((char)rng.Next(1, 256));
}
var key = keyBuilder.ToString();
var partition = resolver.AssignForPartitionKey(key, partitions);
assignedHash.Add(partition);
// If keys were distributed to more than one partition and the minimum number of
// iterations was satisfied, break the loop.
if (assignedHash.Count > requiredAssignments)
{
break;
}
cancellationSource.Token.ThrowIfCancellationRequested();
}
Assert.That(assignedHash.Count, Is.GreaterThanOrEqualTo(requiredAssignments), "Partition keys should have had some level of distribution among partitions.");
}