kubelet

package
v0.10.1-0...-dbf77f2 Latest Latest
Warning

This package is not in the latest version of its module.

Go to latest
Published: Aug 20, 2015 License: Apache-2.0 Imports: 43 Imported by: 0

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

View Source
const (
	RunOnceManifestDelay     = 1 * time.Second
	RunOnceMaxRetries        = 10
	RunOnceRetryDelay        = 1 * time.Second
	RunOnceRetryDelayBackoff = 2
)
View Source
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 = "*"
)
View Source
const ConfigSourceAnnotationKey = "kubernetes.io/config.source"
View Source
const (
	PodInfraContainerImage = "kubernetes/pause:latest"
)

Variables

This section is empty.

Functions

func EtcdClientOrDie

func EtcdClientOrDie(etcdServerList util.StringList, etcdConfigFile string) tools.EtcdClient

TODO: move this into a pkg/tools/etcd_tools

func GetPodFullName

func GetPodFullName(pod *api.BoundPod) string

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

func MonitorCAdvisor(k *Kubelet, cp uint)

TODO: move this into the kubelet itself

func ParsePodFullName

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

func ResolvePort(portReference util.IntOrString, container *api.Container) (int, error)

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

func SetupCapabilities(allowPrivileged bool)

TODO: move this into pkg/capabilities

func SetupEventSending

func SetupEventSending(client *client.Client, hostname string)

func SetupLogging

func SetupLogging()

TODO: Split this up?

Types

type ByCreated

type ByCreated []*docker.Container

func (ByCreated) Len

func (a ByCreated) Len() int

func (ByCreated) Less

func (a ByCreated) Less(i, j int) bool

func (ByCreated) Swap

func (a ByCreated) Swap(i, j int)

type FlushWriter

type FlushWriter struct {
	// contains filtered or unexported fields
}

FlushWriter provides wrapper for responseWriter with HTTP streaming capabilities

func (*FlushWriter) Write

func (fw *FlushWriter) Write(p []byte) (n int, err error)

Write is a FlushWriter implementation of the io.Writer that sends any buffered data to the client.

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)
	GetKubeletContainerLogs(podFullName, containerName, tail string, follow bool, stdout, stderr io.Writer) error
	ServeLogs(w http.ResponseWriter, req *http.Request)
}

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) (*Kubelet, error)

New creates a new Kubelet for use in main

func (*Kubelet) BirthCry

func (kl *Kubelet) BirthCry()

BirthCry sends an event that the kubelet has started up.

func (*Kubelet) GarbageCollectContainers

func (kl *Kubelet) GarbageCollectContainers() error

TODO: Also enforce a maximum total number of containers.

func (*Kubelet) GarbageCollectLoop

func (kl *Kubelet) GarbageCollectLoop()

func (*Kubelet) GetBoundPods

func (kl *Kubelet) GetBoundPods() ([]api.BoundPod, error)

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

func (kl *Kubelet) GetDockerVersion() ([]uint, error)

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

func (kl *Kubelet) GetPodByName(namespace, name string) (*api.BoundPod, bool)

GetPodFullName provides the first pod that matches namespace and name, or false if no such pod can be found.

func (*Kubelet) GetPodStatus

func (kl *Kubelet) GetPodStatus(podFullName string, uid types.UID) (api.PodStatus, error)

GetPodStatus returns information from Docker about the containers in a pod

func (*Kubelet) GetRootInfo

GetRootInfo returns stats (from Cadvisor) of current machine (root container).

func (*Kubelet) Run

func (kl *Kubelet) Run(updates <-chan PodUpdate)

Run starts the kubelet reacting to config updates

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) SyncPods

func (kl *Kubelet) SyncPods(pods []api.BoundPod) error

SyncPods synchronizes the configured list of pods (desired state) with the host current state.

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 RunPodResult struct {
	Pod *api.BoundPod
	Err error
}

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.

func (*Server) ServeHTTP

func (s *Server) ServeHTTP(w http.ResponseWriter, req *http.Request)

ServeHTTP responds to HTTP requests on the Kubelet.

type SourceReadyFn

type SourceReadyFn func(source string) bool

type SyncHandler

type SyncHandler interface {
	SyncPods([]api.BoundPod) error
}

SyncHandler is an interface implemented by Kubelet, for testability

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 server makes it easy to create a kubelet server for various contexts.
Package server makes it easy to create a kubelet server for various contexts.
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.

Jump to

Keyboard shortcuts

? : This menu
/ : Search site
f or F : Jump to
y or Y : Canonical URL