public void TestTripCircuitOnTimeouts()
{
var properties = GetCommandConfig();
ICommandMetrics metrics = GetMetrics(properties);
var cb = new TestCircuitBreaker(properties, metrics);
// this should start as allowing requests
Assert.IsTrue(cb.AllowRequest());
Assert.IsFalse(cb.IsOpen());
metrics.MarkTimeout();
metrics.MarkTimeout();
metrics.MarkTimeout();
metrics.MarkTimeout();
Thread.Sleep(properties.MetricsHealthSnapshotIntervalInMilliseconds);
// this should remain open as the failure threshold is below the percentage limit
Assert.IsFalse(cb.AllowRequest());
Assert.IsTrue(cb.IsOpen());
}
public void TestGetErrorPercentage()
{
var config = GetCommandConfig();
ICommandMetrics metrics = GetMetrics(config);
metrics.MarkSuccess(1000);
Thread.Sleep(config.MetricsHealthSnapshotIntervalInMilliseconds);
Assert.AreEqual(0, metrics.GetErrorPercentage());
metrics.MarkFailure();
Thread.Sleep(config.MetricsHealthSnapshotIntervalInMilliseconds);
Assert.AreEqual(50, metrics.GetErrorPercentage());
metrics.MarkSuccess(100);
metrics.MarkSuccess(100);
Thread.Sleep(config.MetricsHealthSnapshotIntervalInMilliseconds);
Assert.AreEqual(25, metrics.GetErrorPercentage());
metrics.MarkTimeout(5000);
metrics.MarkTimeout(5000);
Thread.Sleep(config.MetricsHealthSnapshotIntervalInMilliseconds);
Assert.AreEqual(50, metrics.GetErrorPercentage());
metrics.MarkSuccess(100);
metrics.MarkSuccess(100);
metrics.MarkSuccess(100);
// latent
Thread.Sleep(config.MetricsHealthSnapshotIntervalInMilliseconds);
metrics.MarkSuccess(5000);
Thread.Sleep(config.MetricsHealthSnapshotIntervalInMilliseconds);
// 6 success + 1 latent success + 1 failure + 2 timeout = 10 total
// latent success not considered error
// error percentage = 1 failure + 2 timeout / 10
Assert.AreEqual(30, metrics.GetErrorPercentage());
}
public void TestTripCircuitOnTimeoutsAboveThreshold()
{
var properties = GetCommandConfig();
ICommandMetrics metrics = GetMetrics(properties);
var cb = new TestCircuitBreaker(properties, metrics);
// this should start as allowing requests
Assert.IsTrue(cb.AllowRequest());
Assert.IsFalse(cb.IsOpen());
metrics.MarkSuccess();
metrics.MarkSuccess();
metrics.MarkSuccess();
metrics.MarkTimeout();
metrics.MarkTimeout();
metrics.MarkTimeout();
metrics.MarkTimeout();
Thread.Sleep(properties.MetricsHealthSnapshotIntervalInMilliseconds);
// this should trip the circuit as the error percentage is above the threshold
Assert.IsFalse(cb.AllowRequest());
Assert.IsTrue(cb.IsOpen());
}