/// <summary>
/// Wait until the container is ready.
/// Refer document @ https://kubernetes.io/docs/concepts/workloads/pods/pod-lifecycle/#pod-phase for the Pod's lifecycle.
/// </summary>
/// <param name="timeout">Timeout on Application Insights data when the container is not ready after the period.</param>
/// <param name="client">Query client to try getting info from the Kubernetes cluster API.</param>
/// <param name="myContainerId">The container that we are interested in.</param>
/// <returns></returns>
private static async Task <bool> SpinWaitContainerReady(TimeSpan timeout, K8sQueryClient client, string myContainerId, ILogger <K8sEnvironment> logger)
{
DateTime tiemoutAt = DateTime.Now.Add(timeout);
Stopwatch stopwatch = new Stopwatch();
stopwatch.Start();
K8sPod myPod = null;
do
{
// When my pod become available and it's status become ready, we recognize the container is ready.
myPod = await client.GetMyPodAsync().ConfigureAwait(false);
if (myPod != null && myPod.GetContainerStatus(myContainerId).Ready)
{
stopwatch.Stop();
logger?.LogDebug(Invariant($"K8s info avaialbe in: {stopwatch.ElapsedMilliseconds} ms."));
return(true);
}
// The time to get the container ready dependes on how much time will a container to be initialized.
// But the minimum seems about 1000ms. Try invoke a probe on readiness every 500ms until the container is ready
// Or it will timeout per the timeout settings.
await Task.Delay(500).ConfigureAwait(false);
} while (DateTime.Now < tiemoutAt);
return(false);
}
/// <summary>
/// Wait until the container is ready.
/// Refer document @ https://kubernetes.io/docs/concepts/workloads/pods/pod-lifecycle/#pod-phase for the Pod's lifecycle.
/// </summary>
/// <param name="timeout">Timeout on Application Insights data when the container is not ready after the period.</param>
/// <param name="client">Query client to try getting info from the Kubernetes cluster API.</param>
/// <param name="myContainerId">The container that we are interested in.</param>
/// <returns></returns>
private async Task <bool> SpinWaitContainerReady(DateTime timeoutAt, K8sQueryClient client, string myContainerId)
{
Stopwatch stopwatch = new Stopwatch();
stopwatch.Start();
K8sPod myPod = null;
do
{
// When my pod become available and it's status become ready, we recognize the container is ready.
try
{
myPod = await client.GetMyPodAsync().ConfigureAwait(false);
}
catch
{
myPod = null;
}
if (myPod != null && myPod.GetContainerStatus(myContainerId).Ready)
{
stopwatch.Stop();
_logger.LogDebug(Invariant($"K8s info avaialbe in: {stopwatch.ElapsedMilliseconds} ms."));
return(true);
}
// The time to get the container ready dependes on how much time will a container to be initialized.
// When there is readiness probe, the pod info will not be available until the initial delay of it is elapsed.
// When there is no readiness probe, the minimum seems about 1000ms.
// Try invoke a probe on readiness every 500ms until the container is ready
// Or it will timeout per the timeout settings.
await Task.Delay(500).ConfigureAwait(false);
} while (DateTime.Now < timeoutAt);
return(false);
}
/// <summary>
/// Async factory method to build the instance of a K8sEnvironment.
/// </summary>
/// <returns></returns>
public async Task <K8sEnvironment> CreateAsync(TimeSpan timeout)
{
K8sEnvironment instance = null;
ILogger <K8sEnvironment> logger = null;
try
{
using (IKubeHttpClient httpClient = _httpClientFactory.Create(_httpClientSettings))
using (K8sQueryClient queryClient = _k8sQueryClientFactory.Create(httpClient))
{
string containerId = _httpClientSettings.ContainerId;
if (await SpinWaitContainerReady(timeout, queryClient, containerId).ConfigureAwait(false))
{
instance = new K8sEnvironment()
{
ContainerID = containerId
};
K8sPod myPod = await queryClient.GetMyPodAsync().ConfigureAwait(false);
instance.myPod = myPod;
logger?.LogDebug(Invariant($"Getting container status of container-id: {containerId}"));
instance.myContainerStatus = myPod.GetContainerStatus(containerId);
IEnumerable <K8sReplicaSet> replicaSetList = await queryClient.GetReplicasAsync().ConfigureAwait(false);
instance.myReplicaSet = myPod.GetMyReplicaSet(replicaSetList);
if (instance.myReplicaSet != null)
{
IEnumerable <K8sDeployment> deploymentList = await queryClient.GetDeploymentsAsync().ConfigureAwait(false);
instance.myDeployment = instance.myReplicaSet.GetMyDeployment(deploymentList);
}
if (instance.myPod != null)
{
IEnumerable <K8sNode> nodeList = await queryClient.GetNodesAsync().ConfigureAwait(false);
string nodeName = instance.myPod.Spec.NodeName;
if (!string.IsNullOrEmpty(nodeName))
{
instance.myNode = nodeList.FirstOrDefault(node => !string.IsNullOrEmpty(node.Metadata?.Name) && node.Metadata.Name.Equals(nodeName, StringComparison.OrdinalIgnoreCase));
}
}
}
else
{
logger?.LogError(Invariant($"Kubernetes info is not available within given time of {timeout.TotalMilliseconds} ms."));
}
}
return(instance);
}
catch (Exception ex)
{
logger?.LogCritical(ex.ToString());
return(null);
}
}
/// <summary>
/// Gets the container status for the pod, where the current container is running upon.
/// </summary>
/// <returns></returns>
public async Task <ContainerStatus> GetMyContainerStatusAsync()
{
EnsureNotDisposed();
string myContainerId = KubeHttpClient.Settings.ContainerId;
K8sPod myPod = await GetMyPodAsync().ConfigureAwait(false);
return(myPod.GetContainerStatus(myContainerId));
}
/// <summary>
/// Async factory method to build the instance of a K8sEnvironment.
/// </summary>
/// <returns></returns>
public async Task <IK8sEnvironment> CreateAsync(DateTime timeoutAt)
{
K8sEnvironment instance = null;
try
{
using (IKubeHttpClient httpClient = _httpClientFactory.Create(_httpClientSettings))
using (K8sQueryClient queryClient = _k8sQueryClientFactory.Create(httpClient))
{
// TODO: See if there's better way to fetch the container id
K8sPod myPod = await SpinWaitUntilGetPod(timeoutAt, queryClient).ConfigureAwait(false);
if (myPod != null)
{
string containerId = null;
if (RuntimeInformation.IsOSPlatform(OSPlatform.Windows))
{
// For Windows, is there a way to fetch the current container id from within the container?
containerId = myPod.Status.ContainerStatuses.First().ContainerID;
}
else if (RuntimeInformation.IsOSPlatform(OSPlatform.Linux))
{
// For Linux, container id could be fetched directly from cGroup.
containerId = _httpClientSettings.ContainerId;
}
// ~
if (await SpinWaitContainerReady(timeoutAt, queryClient, containerId).ConfigureAwait(false))
{
instance = new K8sEnvironment()
{
ContainerID = containerId
};
instance.myPod = myPod;
_logger.LogDebug(Invariant($"Getting container status of container-id: {containerId}"));
instance.myContainerStatus = myPod.GetContainerStatus(containerId);
IEnumerable <K8sReplicaSet> replicaSetList = await queryClient.GetReplicasAsync().ConfigureAwait(false);
instance.myReplicaSet = myPod.GetMyReplicaSet(replicaSetList);
if (instance.myReplicaSet != null)
{
IEnumerable <K8sDeployment> deploymentList = await queryClient.GetDeploymentsAsync().ConfigureAwait(false);
instance.myDeployment = instance.myReplicaSet.GetMyDeployment(deploymentList);
}
if (instance.myPod != null)
{
IEnumerable <K8sNode> nodeList = await queryClient.GetNodesAsync().ConfigureAwait(false);
string nodeName = instance.myPod.Spec.NodeName;
if (!string.IsNullOrEmpty(nodeName))
{
instance.myNode = nodeList.FirstOrDefault(node => !string.IsNullOrEmpty(node.Metadata?.Name) && node.Metadata.Name.Equals(nodeName, StringComparison.OrdinalIgnoreCase));
}
}
}
else
{
_logger.LogError(Invariant($"Kubernetes info is not available before the timeout at {timeoutAt}."));
}
}
else
{
// MyPod is null, meaning query timed out.
_logger.LogCritical("Fail to fetch the pod information in time. Kubernetes info will not be available for the telemetry.");
return(null);
}
}
return(instance);
}
catch (Exception ex)
{
_logger.LogCritical(ex.ToString());
return(null);
}
}