Documentation ¶
Overview ¶
Package kubelet is the package that contains the libraries that drive the Kubelet binary. The kubelet is responsible for node level pod management. It runs on each worker in the cluster.
Index ¶
- Constants
- Variables
- func EtcdClientOrDie(etcdServerList util.StringList, etcdConfigFile string) tools.EtcdClient
- func GetPodFullName(pod *api.BoundPod) string
- func ListenAndServeKubeletServer(host HostInterface, address net.IP, port uint, enableDebuggingHandlers bool)
- func MonitorCAdvisor(k *Kubelet, cp uint)
- func ParsePodFullName(podFullName string) (podName, podNamespace string, podAnnotations map[string]string)
- func ResolvePort(portReference util.IntOrString, container *api.Container) (int, error)
- func SetupCapabilities(allowPrivileged bool)
- func SetupEventSending(client *client.Client, hostname string)
- func SetupLogging()
- type ByCreated
- type FlushWriter
- type HostInterface
- type Kubelet
- func (kl *Kubelet) BirthCry()
- func (kl *Kubelet) ExecInContainer(podFullName string, uid types.UID, container string, cmd []string, ...) error
- func (kl *Kubelet) GarbageCollectContainers() error
- func (kl *Kubelet) GarbageCollectLoop()
- func (kl *Kubelet) GetBoundPods() ([]api.BoundPod, error)
- func (kl *Kubelet) GetCadvisorClient() cadvisorInterface
- func (kl *Kubelet) GetContainerInfo(podFullName string, uid types.UID, containerName string, ...) (*cadvisor.ContainerInfo, error)
- func (kl *Kubelet) GetDockerVersion() ([]uint, error)
- func (kl *Kubelet) GetKubeletContainerLogs(podFullName, containerName, tail string, follow bool, stdout, stderr io.Writer) error
- func (kl *Kubelet) GetMachineInfo() (*cadvisor.MachineInfo, error)
- func (kl *Kubelet) GetPodByName(namespace, name string) (*api.BoundPod, bool)
- func (kl *Kubelet) GetPodStatus(podFullName string, uid types.UID) (api.PodStatus, error)
- func (kl *Kubelet) GetRootInfo(req *cadvisor.ContainerInfoRequest) (*cadvisor.ContainerInfo, error)
- func (kl *Kubelet) PortForward(podFullName string, uid types.UID, port uint16, stream io.ReadWriteCloser) error
- func (kl *Kubelet) Run(updates <-chan PodUpdate)
- func (kl *Kubelet) RunInContainer(podFullName string, uid types.UID, container string, cmd []string) ([]byte, error)
- func (kl *Kubelet) RunOnce(updates <-chan PodUpdate) ([]RunPodResult, error)
- func (kl *Kubelet) ServeLogs(w http.ResponseWriter, req *http.Request)
- func (kl *Kubelet) SetCadvisorClient(c cadvisorInterface)
- func (kl *Kubelet) StreamingConnectionIdleTimeout() time.Duration
- func (kl *Kubelet) SyncPods(pods []api.BoundPod) error
- type PodOperation
- type PodUpdate
- type RunPodResult
- type Server
- type SourceReadyFn
- type SyncHandler
Constants ¶
const ( RunOnceManifestDelay = 1 * time.Second RunOnceMaxRetries = 10 RunOnceRetryDelay = 1 * time.Second RunOnceRetryDelayBackoff = 2 )
const ( // This is the current pod configuration SET PodOperation = iota // Pods with the given ids are new to this source ADD // Pods with the given ids have been removed from this source REMOVE // Pods with the given ids have been updated in this source UPDATE // These constants identify the sources of pods // Updates from a file FileSource = "file" // Updates from etcd EtcdSource = "etcd" // Updates from querying a web page HTTPSource = "http" // Updates received to the kubelet server ServerSource = "server" // Updates from Kubernetes API Server ApiserverSource = "api" // Updates from all sources AllSource = "*" )
const ConfigSourceAnnotationKey = "kubernetes.io/config.source"
const (
PodInfraContainerImage = "kubernetes/pause:latest"
)
Variables ¶
var ( // ErrNoKubeletContainers returned when there are not containers managed by the kubelet (ie: either no containers on the node, or none that the kubelet cares about). ErrNoKubeletContainers = errors.New("no containers managed by kubelet") // ErrContainerNotFound returned when a container in the given pod with the given container name was not found, amongst those managed by the kubelet. ErrContainerNotFound = errors.New("no matching container") // ErrCadvisorApiFailure returned when cadvisor couldn't retrieve stats for the given container, either because it isn't running or it was confused by the request ErrCadvisorApiFailure = errors.New("failed to retrieve cadvisor stats") )
Functions ¶
func EtcdClientOrDie ¶ added in v0.2.1
func EtcdClientOrDie(etcdServerList util.StringList, etcdConfigFile string) tools.EtcdClient
TODO: move this into a pkg/tools/etcd_tools
func GetPodFullName ¶
GetPodFullName returns a name that uniquely identifies a pod across all config sources.
func ListenAndServeKubeletServer ¶
func ListenAndServeKubeletServer(host HostInterface, address net.IP, port uint, enableDebuggingHandlers bool)
ListenAndServeKubeletServer initializes a server to respond to HTTP network requests on the Kubelet.
func MonitorCAdvisor ¶ added in v0.2.1
TODO: move this into the kubelet itself
func ParsePodFullName ¶ added in v0.2.1
func ParsePodFullName(podFullName string) (podName, podNamespace string, podAnnotations map[string]string)
ParsePodFullName unpacks a pod full name and returns the pod name, namespace, and annotations. If the pod full name is invalid, empty strings are returend.
func ResolvePort ¶
ResolvePort attempts to turn a IntOrString port reference into a concrete port number. If portReference has an int value, it is treated as a literal, and simply returns that value. If portReference is a string, an attempt is first made to parse it as an integer. If that fails, an attempt is made to find a port with the same name in the container spec. If a port with the same name is found, it's ContainerPort value is returned. If no matching port is found, an error is returned.
func SetupCapabilities ¶ added in v0.2.1
func SetupCapabilities(allowPrivileged bool)
TODO: move this into pkg/capabilities
func SetupEventSending ¶ added in v0.2.1
Types ¶
type FlushWriter ¶
type FlushWriter struct {
// contains filtered or unexported fields
}
FlushWriter provides wrapper for responseWriter with HTTP streaming capabilities
type HostInterface ¶
type HostInterface interface { GetContainerInfo(podFullName string, uid types.UID, containerName string, req *info.ContainerInfoRequest) (*info.ContainerInfo, error) GetRootInfo(req *info.ContainerInfoRequest) (*info.ContainerInfo, error) GetDockerVersion() ([]uint, error) GetMachineInfo() (*info.MachineInfo, error) GetBoundPods() ([]api.BoundPod, error) GetPodByName(namespace, name string) (*api.BoundPod, bool) GetPodStatus(name string, uid types.UID) (api.PodStatus, error) RunInContainer(name string, uid types.UID, container string, cmd []string) ([]byte, error) ExecInContainer(name string, uid types.UID, container string, cmd []string, in io.Reader, out, err io.WriteCloser, tty bool) error GetKubeletContainerLogs(podFullName, containerName, tail string, follow bool, stdout, stderr io.Writer) error ServeLogs(w http.ResponseWriter, req *http.Request) PortForward(name string, uid types.UID, port uint16, stream io.ReadWriteCloser) error StreamingConnectionIdleTimeout() time.Duration }
HostInterface contains all the kubelet methods required by the server. For testablitiy.
type Kubelet ¶
type Kubelet struct {
// contains filtered or unexported fields
}
Kubelet is the main kubelet implementation.
func NewMainKubelet ¶
func NewMainKubelet( hostname string, dockerClient dockertools.DockerInterface, etcdClient tools.EtcdClient, kubeClient *client.Client, rootDirectory string, podInfraContainerImage string, resyncInterval time.Duration, pullQPS float32, pullBurst int, minimumGCAge time.Duration, maxContainerCount int, sourceReady SourceReadyFn, clusterDomain string, clusterDNS net.IP, masterServiceNamespace string, volumePlugins []volume.Plugin, streamingConnectionIdleTimeout time.Duration) (*Kubelet, error)
New creates a new Kubelet for use in main
func (*Kubelet) BirthCry ¶ added in v0.2.1
func (kl *Kubelet) BirthCry()
BirthCry sends an event that the kubelet has started up.
func (*Kubelet) ExecInContainer ¶ added in v0.4.1
func (kl *Kubelet) ExecInContainer(podFullName string, uid types.UID, container string, cmd []string, stdin io.Reader, stdout, stderr io.WriteCloser, tty bool) error
ExecInContainer executes a command in a container, connecting the supplied stdin/stdout/stderr to the command's IO streams.
func (*Kubelet) GarbageCollectContainers ¶ added in v0.2.1
TODO: Also enforce a maximum total number of containers.
func (*Kubelet) GarbageCollectLoop ¶ added in v0.2.1
func (kl *Kubelet) GarbageCollectLoop()
func (*Kubelet) GetBoundPods ¶ added in v0.2.1
GetBoundPods returns all pods bound to the kubelet and their spec
func (*Kubelet) GetCadvisorClient ¶
func (kl *Kubelet) GetCadvisorClient() cadvisorInterface
GetCadvisorClient gets the cadvisor client.
func (*Kubelet) GetContainerInfo ¶
func (kl *Kubelet) GetContainerInfo(podFullName string, uid types.UID, containerName string, req *cadvisor.ContainerInfoRequest) (*cadvisor.ContainerInfo, error)
GetContainerInfo returns stats (from Cadvisor) for a container.
func (*Kubelet) GetDockerVersion ¶ added in v0.3.2
Returns Docker version for this Kubelet.
func (*Kubelet) GetKubeletContainerLogs ¶
func (kl *Kubelet) GetKubeletContainerLogs(podFullName, containerName, tail string, follow bool, stdout, stderr io.Writer) error
GetKubeletContainerLogs returns logs from the container The second parameter of GetPodStatus and FindPodContainer methods represents pod UUID, which is allowed to be blank TODO: this method is returning logs of random container attempts, when it should be returning the most recent attempt or all of them.
func (*Kubelet) GetMachineInfo ¶
func (kl *Kubelet) GetMachineInfo() (*cadvisor.MachineInfo, error)
func (*Kubelet) GetPodByName ¶ added in v0.2.1
GetPodFullName provides the first pod that matches namespace and name, or false if no such pod can be found.
func (*Kubelet) GetPodStatus ¶ added in v0.2.2
GetPodStatus returns information from Docker about the containers in a pod
func (*Kubelet) GetRootInfo ¶
func (kl *Kubelet) GetRootInfo(req *cadvisor.ContainerInfoRequest) (*cadvisor.ContainerInfo, error)
GetRootInfo returns stats (from Cadvisor) of current machine (root container).
func (*Kubelet) PortForward ¶ added in v0.4.1
func (kl *Kubelet) PortForward(podFullName string, uid types.UID, port uint16, stream io.ReadWriteCloser) error
PortForward connects to the pod's port and copies data between the port and the stream.
func (*Kubelet) RunInContainer ¶
func (kl *Kubelet) RunInContainer(podFullName string, uid types.UID, container string, cmd []string) ([]byte, error)
Run a command in a container, returns the combined stdout, stderr as an array of bytes
func (*Kubelet) RunOnce ¶
func (kl *Kubelet) RunOnce(updates <-chan PodUpdate) ([]RunPodResult, error)
RunOnce polls from one configuration update and run the associated pods.
func (*Kubelet) ServeLogs ¶
func (kl *Kubelet) ServeLogs(w http.ResponseWriter, req *http.Request)
Returns logs of current machine.
func (*Kubelet) SetCadvisorClient ¶
func (kl *Kubelet) SetCadvisorClient(c cadvisorInterface)
SetCadvisorClient sets the cadvisor client in a thread-safe way.
func (*Kubelet) StreamingConnectionIdleTimeout ¶ added in v0.4.1
type PodOperation ¶
type PodOperation int
PodOperation defines what changes will be made on a pod configuration.
type PodUpdate ¶
type PodUpdate struct { Pods []api.BoundPod Op PodOperation Source string }
PodUpdate defines an operation sent on the channel. You can add or remove single services by sending an array of size one and Op == ADD|REMOVE (with REMOVE, only the ID is required). For setting the state of the system to a given state for this source configuration, set Pods as desired and Op to SET, which will reset the system state to that specified in this operation for this source channel. To remove all pods, set Pods to empty object and Op to SET.
Additionally, Pods should never be nil - it should always point to an empty slice. While functionally similar, this helps our unit tests properly check that the correct PodUpdates are generated.
type RunPodResult ¶
type Server ¶
type Server struct {
// contains filtered or unexported fields
}
Server is a http.Handler which exposes kubelet functionality over HTTP.
func NewServer ¶
func NewServer(host HostInterface, enableDebuggingHandlers bool) Server
NewServer initializes and configures a kubelet.Server object to handle HTTP requests.
func (*Server) InstallDebuggingHandlers ¶
func (s *Server) InstallDebuggingHandlers()
InstallDeguggingHandlers registers the HTTP request patterns that serve logs or run commands/containers
func (*Server) InstallDefaultHandlers ¶
func (s *Server) InstallDefaultHandlers()
InstallDefaultHandlers registers the default set of supported HTTP request patterns with the mux.
type SourceReadyFn ¶ added in v0.2.1
type SyncHandler ¶
SyncHandler is an interface implemented by Kubelet, for testability
Source Files ¶
Directories ¶
Path | Synopsis |
---|---|
Reads the pod configuration from the Kubernetes apiserver.
|
Reads the pod configuration from the Kubernetes apiserver. |
Package envvars is the package that build the environment variables that kubernetes provides to the containers run by it.
|
Package envvars is the package that build the environment variables that kubernetes provides to the containers run by it. |
Package leaky holds bits of kubelet that should be internal but have leaked out through bad abstractions.
|
Package leaky holds bits of kubelet that should be internal but have leaked out through bad abstractions. |
Package volume includes internal representations of external volume types as well as utility methods required to mount/unmount volumes to kubelets.
|
Package volume includes internal representations of external volume types as well as utility methods required to mount/unmount volumes to kubelets. |