public MicroserviceInstanceDTO Map(IReadonlyMicroserviceInstance instance)
{
return(new MicroserviceInstanceDTO
{
Uri = instance.Uri
});
}
public Result <Uri> Execute(IEnumerable <IReadonlyMicroserviceInstance> instances)
{
if (instances == null || !instances.Any())
{
return(Result <Uri> .Failure(Messages.CanNotExecuteLoadBalancingStrategyForZeroAvailableInstances()));
}
IInstanceMetric bestMetric = new MemoryUsageMetric(double.MaxValue);
IReadonlyMicroserviceInstance bestInstance = null;
foreach (var instance in instances)
{
if (TryGetProcessorUsageMetric(instance, out var metric))
{
if (bestMetric.CompareTo(metric) >= 0)
{
bestMetric = metric;
bestInstance = instance;
}
}
}
return(!instances.Any() || bestInstance == null ?
Result <Uri> .Failure(Messages.CanNotFindSuitableTarget(instances)) :
Result <Uri> .Success(bestInstance.Uri));
}
public MetricMetadata GetFrom(IReadonlyMicroserviceInstance microserviceInstance)
{
return(new MetricMetadata
{
Instance = microserviceInstance.Uri.OriginalString,
Job = microserviceInstance.MicroServiceName
});
}
private static bool TryGetProcessorUsageMetric(IReadonlyMicroserviceInstance instance, out IInstanceMetric?metric)
{
if (instance?.Metrics == null)
{
metric = null;
return(false);
}
metric = instance.Metrics
.FirstOrDefault(m =>
m.Key == MetricType.ProcessorUsage)
.Value;
return(metric != null);
}
