kubectl

package
v0.17.0 Latest Latest
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 Go to latest Published: May 12, 2015 License: Apache-2.0 Imports: 37 Imported by: 0

Documentation

Overview

A set of common functions needed by cmd/kubectl and pkg/kubectl packages.

Package kubectl is a set of libraries that are used by the kubectl command line tool. They are separated out into a library to support unit testing. Most functionality should be included in this package, and the main kubectl should really just be an entry point.

A set of common functions needed by cmd/kubectl and pkg/kubectl packages.

Index

Constants

View Source 
const MaxRetries = 3

Variables

This section is empty.

Functions

func AbortRollingUpdate added in v0.17.0 

func AbortRollingUpdate(c *RollingUpdaterConfig)

func AddDeploymentKeyToReplicationController added in v0.17.0 

func AddDeploymentKeyToReplicationController(oldRc *api.ReplicationController, client client.Interface, deploymentKey, deploymentValue, namespace string, out io.Writer) (*api.ReplicationController, error)

func AddJsonFilenameFlag added in v0.16.0 

func AddJsonFilenameFlag(cmd *cobra.Command, value *util.StringList, usage string)

func CreateNewControllerFromCurrentController added in v0.17.0 

func CreateNewControllerFromCurrentController(c *client.Client, namespace, oldName, newName, image, deploymentKey string) (*api.ReplicationController, error)

func DescribableResources added in v0.16.0 

func DescribableResources() []string

List of all resource types we can describe

func DescribeEvents added in v0.16.0 

func DescribeEvents(el *api.EventList, w io.Writer)

func FindSourceController added in v0.17.0 

func FindSourceController(r RollingUpdaterClient, namespace, name string) (*api.ReplicationController, error)

func GetApiVersions added in v0.14.0 

func GetApiVersions(w io.Writer, kubeClient client.Interface)

func GetClientVersion 

func GetClientVersion(w io.Writer)

func GetNextControllerAnnotation added in v0.17.0 

func GetNextControllerAnnotation(rc *api.ReplicationController) (string, bool)

func GetVersion 

func GetVersion(w io.Writer, kubeClient client.Interface)

func IsNoSuchReaperError added in v0.16.0 

func IsNoSuchReaperError(err error) bool

func LoadExistingNextReplicationController added in v0.17.0 

func LoadExistingNextReplicationController(c *client.Client, namespace, newName string) (*api.ReplicationController, error)

func MakeLabels added in v0.11.0 

func MakeLabels(labels map[string]string) string

func MakeParams added in v0.9.0 

func MakeParams(cmd *cobra.Command, params []GeneratorParam) map[string]string

MakeParams is a utility that creates generator parameters from a command line

func ParseLabels added in v0.9.0 

func ParseLabels(labelString string) (map[string]string, error)

ParseLabels turns a string representation of a label set into a map[string]string

func Rename added in v0.17.0 

func Rename(c RollingUpdaterClient, rc *api.ReplicationController, newName string) error

func ResizeCondition added in v0.13.0 

func ResizeCondition(r Resizer, precondition *ResizePrecondition, namespace, name string, count uint) wait.ConditionFunc

ResizeCondition is a closure around Resize that facilitates retries via util.wait

func SetNextControllerAnnotation added in v0.17.0 

func SetNextControllerAnnotation(rc *api.ReplicationController, name string)

func UpdateExistingReplicationController added in v0.17.0 

func UpdateExistingReplicationController(c client.Interface, oldRc *api.ReplicationController, namespace, newName, deploymentKey, deploymentValue string, out io.Writer) (*api.ReplicationController, error)

func ValidateParams added in v0.9.0 

func ValidateParams(paramSpec []GeneratorParam, params map[string]string) error

ValidateParams ensures that all required params are present in the params map

func WatchLoop 

func WatchLoop(w watch.Interface, fn func(watch.Event) error)

WatchLoop loops, passing events in w to fn. If user sends interrupt signal, shut down cleanly. Otherwise, never return.

Types

type BasicReplicationController added in v0.9.0 

type BasicReplicationController struct{}

func (BasicReplicationController) Generate added in v0.9.0 

func (BasicReplicationController) Generate(params map[string]string) (runtime.Object, error)

func (BasicReplicationController) ParamNames added in v0.9.0 

func (BasicReplicationController) ParamNames() []GeneratorParam

type ControllerResizeError added in v0.13.0 

type ControllerResizeError struct {
	FailureType     ControllerResizeErrorType
	ResourceVersion string
	ActualError     error
}

A ControllerResizeError is returned when a the resize request passes preconditions but fails to actually resize the controller.

func (ControllerResizeError) Error added in v0.13.0 

func (c ControllerResizeError) Error() string

type ControllerResizeErrorType added in v0.13.0 

type ControllerResizeErrorType int
const (
	ControllerResizeGetFailure ControllerResizeErrorType = iota
	ControllerResizeUpdateFailure
)

type Describer 

type Describer interface {
	Describe(namespace, name string) (output string, err error)
}

Describer generates output for the named resource or an error if the output could not be generated. Implementors typically abstract the retrieval of the named object from a remote server.

func DescriberFor 

func DescriberFor(kind string, c *client.Client) (Describer, bool)

Describer returns the default describe functions for each of the standard Kubernetes types.

type Describers added in v0.13.1 

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

Describers implements ObjectDescriber against functions registered via Add. Those functions can be strongly typed. Types are exactly matched (no conversion or assignable checks).

func (*Describers) Add added in v0.13.1 

func (d *Describers) Add(fns ...interface{}) error

Add adds one or more describer functions to the Describer. The passed function must match the signature: 

func(...) (string, error)

Any number of arguments may be provided.

func (*Describers) DescribeObject added in v0.13.1 

func (d *Describers) DescribeObject(exact interface{}, extra ...interface{}) (string, error)

DescribeObject implements ObjectDescriber and will attempt to print the provided object to a string, if at least one describer function has been registered with the exact types passed, or if any describer can print the exact object in its first argument (the remainder will be provided empty values). If no function registered with Add can satisfy the passed objects, an ErrNoDescriber will be returned TODO: reorder and partial match extra.

type ErrNoDescriber added in v0.13.1 

type ErrNoDescriber struct {
	Types []string
}

ErrNoDescriber is a structured error indicating the provided object or objects cannot be described.

func (ErrNoDescriber) Error added in v0.13.1 

func (e ErrNoDescriber) Error() string

Error implements the error interface.

type Generator added in v0.9.0 

type Generator interface {
	// Generate creates an API object given a set of parameters
	Generate(params map[string]string) (runtime.Object, error)
	// ParamNames returns the list of parameters that this generator uses
	ParamNames() []GeneratorParam
}

Generator is an interface for things that can generate API objects from input parameters.

type GeneratorParam added in v0.9.0 

type GeneratorParam struct {
	Name     string
	Required bool
}

GeneratorParam is a parameter for a generator TODO: facilitate structured json generator input schemes

type HumanReadablePrinter 

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

HumanReadablePrinter is an implementation of ResourcePrinter which attempts to provide more elegant output. It is not threadsafe, but you may call PrintObj repeatedly; headers will only be printed if the object type changes. This makes it useful for printing items recieved from watches.

func NewHumanReadablePrinter 

func NewHumanReadablePrinter(noHeaders bool) *HumanReadablePrinter

NewHumanReadablePrinter creates a HumanReadablePrinter.

func (*HumanReadablePrinter) HandledResources added in v0.16.0 

func (h *HumanReadablePrinter) HandledResources() []string

func (*HumanReadablePrinter) Handler 

func (h *HumanReadablePrinter) Handler(columns []string, printFunc interface{}) error

Handler adds a print handler with a given set of columns to HumanReadablePrinter instance. printFunc is the function that will be called to print an object. It must be of the following type: 

func printFunc(object ObjectType, w io.Writer) error

where ObjectType is the type of the object that will be printed.

func (*HumanReadablePrinter) PrintObj 

func (h *HumanReadablePrinter) PrintObj(obj runtime.Object, output io.Writer) error

PrintObj prints the obj in a human-friendly format according to the type of the obj.

type JSONPrinter 

type JSONPrinter struct {
}

JSONPrinter is an implementation of ResourcePrinter which outputs an object as JSON.

func (*JSONPrinter) PrintObj 

func (p *JSONPrinter) PrintObj(obj runtime.Object, w io.Writer) error

PrintObj is an implementation of ResourcePrinter.PrintObj which simply writes the object to the Writer.

type LimitRangeDescriber added in v0.10.1 

type LimitRangeDescriber struct {
	client.Interface
}

LimitRangeDescriber generates information about a limit range

func (*LimitRangeDescriber) Describe added in v0.10.1 

func (d *LimitRangeDescriber) Describe(namespace, name string) (string, error)

type NamespaceInfo 

type NamespaceInfo struct {
	Namespace string
}

type NoSuchReaperError added in v0.16.0 

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

func (*NoSuchReaperError) Error added in v0.16.0 

func (n *NoSuchReaperError) Error() string

type NodeDescriber added in v0.13.0 

type NodeDescriber struct {
	client.Interface
}

NodeDescriber generates information about a node.

func (*NodeDescriber) Describe added in v0.13.0 

func (d *NodeDescriber) Describe(namespace, name string) (string, error)

type ObjectDescriber added in v0.13.1 

type ObjectDescriber interface {
	DescribeObject(object interface{}, extra ...interface{}) (output string, err error)
}

ObjectDescriber is an interface for displaying arbitrary objects with extra information. Use when an object is in hand (on disk, or already retrieved). Implementors may ignore the additional information passed on extra, or use it by default. ObjectDescribers may return ErrNoDescriber if no suitable describer is found. 

var DefaultObjectDescriber ObjectDescriber

DefaultObjectDescriber can describe the default Kubernetes objects.

type OutputVersionMapper added in v0.9.0 

type OutputVersionMapper struct {
	meta.RESTMapper
	OutputVersion string
}

OutputVersionMapper is a RESTMapper that will prefer mappings that correspond to a preferred output version (if feasible)

func (OutputVersionMapper) RESTMapping added in v0.9.0 

func (m OutputVersionMapper) RESTMapping(kind string, versions ...string) (*meta.RESTMapping, error)

RESTMapping implements meta.RESTMapper by prepending the output version to the preferred version list.

type PersistentVolumeClaimDescriber added in v0.15.0 

type PersistentVolumeClaimDescriber struct {
	client.Interface
}

func (*PersistentVolumeClaimDescriber) Describe added in v0.15.0 

func (d *PersistentVolumeClaimDescriber) Describe(namespace, name string) (string, error)

type PersistentVolumeDescriber added in v0.15.0 

type PersistentVolumeDescriber struct {
	client.Interface
}

func (*PersistentVolumeDescriber) Describe added in v0.15.0 

func (d *PersistentVolumeDescriber) Describe(namespace, name string) (string, error)

type PodDescriber 

type PodDescriber struct {
	client.Interface
}

PodDescriber generates information about a pod and the replication controllers that create it.

func (*PodDescriber) Describe 

func (d *PodDescriber) Describe(namespace, name string) (string, error)

type PodReaper added in v0.9.1 

type PodReaper struct {
	client.Interface
}

func (*PodReaper) Stop added in v0.9.1 

func (reaper *PodReaper) Stop(namespace, name string, gracePeriod *api.DeleteOptions) (string, error)

type PreconditionError added in v0.9.0 

type PreconditionError struct {
	Precondition  string
	ExpectedValue string
	ActualValue   string
}

A PreconditionError is returned when a replication controller fails to match the resize preconditions passed to kubectl.

func (PreconditionError) Error added in v0.9.0 

func (pe PreconditionError) Error() string

type ProxyServer 

type ProxyServer struct {
	httputil.ReverseProxy
}

ProxyServer is a http.Handler which proxies Kubernetes APIs to remote API server.

func NewProxyServer 

func NewProxyServer(filebase string, apiProxyPrefix string, staticPrefix string, cfg *client.Config) (*ProxyServer, error)

NewProxyServer creates and installs a new ProxyServer. It automatically registers the created ProxyServer to http.DefaultServeMux.

func (*ProxyServer) Serve 

func (s *ProxyServer) Serve(port int) error

Serve starts the server (http.DefaultServeMux) on given port, loops forever.

type RESTClient 

type RESTClient interface {
	Get() *client.Request
	Post() *client.Request
	Delete() *client.Request
	Put() *client.Request
}

RESTClient is a client helper for dealing with RESTful resources in a generic way.

type Reaper added in v0.9.1 

type Reaper interface {
	Stop(namespace, name string, gracePeriod *api.DeleteOptions) (string, error)
}

A Reaper handles terminating an object as gracefully as possible.

func ReaperFor added in v0.9.1 

func ReaperFor(kind string, c client.Interface) (Reaper, error)

type ReplicationControllerDescriber 

type ReplicationControllerDescriber struct {
	client.Interface
}

ReplicationControllerDescriber generates information about a replication controller and the pods it has created.

func (*ReplicationControllerDescriber) Describe 

func (d *ReplicationControllerDescriber) Describe(namespace, name string) (string, error)

type ReplicationControllerReaper added in v0.9.1 

type ReplicationControllerReaper struct {
	client.Interface
	// contains filtered or unexported fields
}

func (*ReplicationControllerReaper) Stop added in v0.9.1 

func (reaper *ReplicationControllerReaper) Stop(namespace, name string, gracePeriod *api.DeleteOptions) (string, error)

type ReplicationControllerResizer added in v0.9.0 

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

func (*ReplicationControllerResizer) Resize added in v0.9.0 

func (resizer *ReplicationControllerResizer) Resize(namespace, name string, newSize uint, preconditions *ResizePrecondition, retry, waitForReplicas *RetryParams) error

Resize updates a ReplicationController to a new size, with optional precondition check (if preconditions is not nil), optional retries (if retry is not nil), and then optionally waits for it's replica count to reach the new value (if wait is not nil).

func (*ReplicationControllerResizer) ResizeSimple added in v0.15.0 

func (resizer *ReplicationControllerResizer) ResizeSimple(namespace, name string, preconditions *ResizePrecondition, newSize uint) (string, error)

type ResizePrecondition added in v0.9.0 

type ResizePrecondition struct {
	Size            int
	ResourceVersion string
}

ResizePrecondition describes a condition that must be true for the resize to take place If CurrentSize == -1, it is ignored. If CurrentResourceVersion is the empty string, it is ignored. Otherwise they must equal the values in the replication controller for it to be valid.

func (*ResizePrecondition) Validate added in v0.9.0 

func (precondition *ResizePrecondition) Validate(controller *api.ReplicationController) error

Validate ensures that the preconditions match. Returns nil if they are valid, an error otherwise

type Resizer added in v0.9.0 

type Resizer interface {
	// Resize resizes the named resource after checking preconditions. It optionally
	// retries in the event of resource version mismatch (if retry is not nil),
	// and optionally waits until the status of the resource matches newSize (if wait is not nil)
	Resize(namespace, name string, newSize uint, preconditions *ResizePrecondition, retry, wait *RetryParams) error
	// ResizeSimple does a simple one-shot attempt at resizing - not useful on it's own, but
	// a necessary building block for Resize
	ResizeSimple(namespace, name string, preconditions *ResizePrecondition, newSize uint) (string, error)
}

func ResizerFor added in v0.9.0 

func ResizerFor(kind string, c ResizerClient) (Resizer, error)

type ResizerClient added in v0.16.0 

type ResizerClient interface {
	GetReplicationController(namespace, name string) (*api.ReplicationController, error)
	UpdateReplicationController(namespace string, rc *api.ReplicationController) (*api.ReplicationController, error)
	ControllerHasDesiredReplicas(rc *api.ReplicationController) wait.ConditionFunc
}

ResizerClient abstracts access to ReplicationControllers.

func NewResizerClient added in v0.16.0 

func NewResizerClient(c client.Interface) ResizerClient

type ResourcePrinter 

type ResourcePrinter interface {
	// Print receives a runtime object, formats it and prints it to a writer.
	PrintObj(runtime.Object, io.Writer) error
}

ResourcePrinter is an interface that knows how to print runtime objects.

func GetPrinter 

func GetPrinter(format, formatArgument string) (ResourcePrinter, bool, error)

GetPrinter takes a format type, an optional format argument. It will return true if the format is generic (untyped), otherwise it will return false. The printer is agnostic to schema versions, so you must send arguments to PrintObj in the version you wish them to be shown using a VersionedPrinter (typically when generic is true).

func NewVersionedPrinter added in v0.9.0 

func NewVersionedPrinter(printer ResourcePrinter, convertor runtime.ObjectConvertor, version ...string) ResourcePrinter

NewVersionedPrinter wraps a printer to convert objects to a known API version prior to printing.

type ResourcePrinterFunc added in v0.9.0 

type ResourcePrinterFunc func(runtime.Object, io.Writer) error

ResourcePrinterFunc is a function that can print objects

func (ResourcePrinterFunc) PrintObj added in v0.9.0 

func (fn ResourcePrinterFunc) PrintObj(obj runtime.Object, w io.Writer) error

PrintObj implements ResourcePrinter

type ResourceQuotaDescriber added in v0.10.1 

type ResourceQuotaDescriber struct {
	client.Interface
}

ResourceQuotaDescriber generates information about a resource quota

func (*ResourceQuotaDescriber) Describe added in v0.10.1 

func (d *ResourceQuotaDescriber) Describe(namespace, name string) (string, error)

type RetryParams added in v0.15.0 

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

type RollingUpdater added in v0.9.0 

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

RollingUpdater provides methods for updating replicated pods in a predictable, fault-tolerant way.

func NewRollingUpdater added in v0.9.0 

func NewRollingUpdater(namespace string, c RollingUpdaterClient) *RollingUpdater

NewRollingUpdater creates a RollingUpdater from a client

func (*RollingUpdater) Update added in v0.9.0 

func (r *RollingUpdater) Update(config *RollingUpdaterConfig) error

Update all pods for a ReplicationController (oldRc) by creating a new controller (newRc) with 0 replicas, and synchronously resizing oldRc,newRc by 1 until oldRc has 0 replicas and newRc has the original # of desired replicas. Cleanup occurs based on a RollingUpdaterCleanupPolicy.

If an update from newRc to oldRc is already in progress, we attempt to drive it to completion. If an error occurs at any step of the update, the error will be returned.

TODO: make this handle performing a rollback of a partially completed rollout.

type RollingUpdaterCleanupPolicy added in v0.16.0 

type RollingUpdaterCleanupPolicy string

RollingUpdaterCleanupPolicy is a cleanup action to take after the deployment is complete. 

const (
	// DeleteRollingUpdateCleanupPolicy means delete the old controller.
	DeleteRollingUpdateCleanupPolicy RollingUpdaterCleanupPolicy = "Delete"
	// PreserveRollingUpdateCleanupPolicy means keep the old controller.
	PreserveRollingUpdateCleanupPolicy RollingUpdaterCleanupPolicy = "Preserve"
	// RenameRollingUpdateCleanupPolicy means delete the old controller, and rename
	// the new controller to the name of the old controller.
	RenameRollingUpdateCleanupPolicy RollingUpdaterCleanupPolicy = "Rename"
)

type RollingUpdaterClient added in v0.16.0 

type RollingUpdaterClient interface {
	ListReplicationControllers(namespace string, selector labels.Selector) (*api.ReplicationControllerList, error)
	GetReplicationController(namespace, name string) (*api.ReplicationController, error)
	UpdateReplicationController(namespace string, rc *api.ReplicationController) (*api.ReplicationController, error)
	CreateReplicationController(namespace string, rc *api.ReplicationController) (*api.ReplicationController, error)
	DeleteReplicationController(namespace, name string) error
	ControllerHasDesiredReplicas(rc *api.ReplicationController) wait.ConditionFunc
}

RollingUpdaterClient abstracts access to ReplicationControllers.

func NewRollingUpdaterClient added in v0.16.0 

func NewRollingUpdaterClient(c client.Interface) RollingUpdaterClient

type RollingUpdaterConfig added in v0.16.0 

type RollingUpdaterConfig struct {
	// Out is a writer for progress output.
	Out io.Writer
	// OldRC is an existing controller to be replaced.
	OldRc *api.ReplicationController
	// NewRc is a controller that will take ownership of updated pods (will be
	// created if needed).
	NewRc *api.ReplicationController
	// UpdatePeriod is the time to wait between individual pod updates.
	UpdatePeriod time.Duration
	// Interval is the time to wait between polling controller status after
	// update.
	Interval time.Duration
	// Timeout is the time to wait for controller updates before giving up.
	Timeout time.Duration
	// CleanupPolicy defines the cleanup action to take after the deployment is
	// complete.
	CleanupPolicy RollingUpdaterCleanupPolicy
}

RollingUpdaterConfig is the configuration for a rolling deployment process.

type ServiceDescriber 

type ServiceDescriber struct {
	client.Interface
}

ServiceDescriber generates information about a service.

func (*ServiceDescriber) Describe 

func (d *ServiceDescriber) Describe(namespace, name string) (string, error)

type ServiceGenerator added in v0.11.0 

type ServiceGenerator struct{}

func (ServiceGenerator) Generate added in v0.11.0 

func (ServiceGenerator) Generate(params map[string]string) (runtime.Object, error)

func (ServiceGenerator) ParamNames added in v0.11.0 

func (ServiceGenerator) ParamNames() []GeneratorParam

type ServiceReaper added in v0.9.1 

type ServiceReaper struct {
	client.Interface
}

func (*ServiceReaper) Stop added in v0.9.1 

func (reaper *ServiceReaper) Stop(namespace, name string, gracePeriod *api.DeleteOptions) (string, error)

type ShortcutExpander added in v0.9.0 

type ShortcutExpander struct {
	meta.RESTMapper
}

ShortcutExpander is a RESTMapper that can be used for Kubernetes resources.

func (ShortcutExpander) VersionAndKindForResource added in v0.9.0 

func (e ShortcutExpander) VersionAndKindForResource(resource string) (defaultVersion, kind string, err error)

VersionAndKindForResource implements meta.RESTMapper. It expands the resource first, then invokes the wrapped mapper.

type SortableEvents added in v0.8.0 

type SortableEvents []api.Event

SortableEvents implements sort.Interface for []api.Event based on the Timestamp field

func (SortableEvents) Len added in v0.8.0 

func (list SortableEvents) Len() int

func (SortableEvents) Less added in v0.8.0 

func (list SortableEvents) Less(i, j int) bool

func (SortableEvents) Swap added in v0.8.0 

func (list SortableEvents) Swap(i, j int)

type SortableResourceNames added in v0.10.1 

type SortableResourceNames []api.ResourceName

func (SortableResourceNames) Len added in v0.10.1 

func (list SortableResourceNames) Len() int

func (SortableResourceNames) Less added in v0.10.1 

func (list SortableResourceNames) Less(i, j int) bool

func (SortableResourceNames) Swap added in v0.10.1 

func (list SortableResourceNames) Swap(i, j int)

type TemplatePrinter 

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

TemplatePrinter is an implementation of ResourcePrinter which formats data with a Go Template.

func NewTemplatePrinter 

func NewTemplatePrinter(tmpl []byte) (*TemplatePrinter, error)

func (*TemplatePrinter) PrintObj 

func (p *TemplatePrinter) PrintObj(obj runtime.Object, w io.Writer) error

PrintObj formats the obj with the Go Template.

type VersionedPrinter added in v0.9.0 

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

VersionedPrinter takes runtime objects and ensures they are converted to a given API version prior to being passed to a nested printer.

func (*VersionedPrinter) PrintObj added in v0.9.0 

func (p *VersionedPrinter) PrintObj(obj runtime.Object, w io.Writer) error

PrintObj implements ResourcePrinter

type YAMLPrinter 

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

YAMLPrinter is an implementation of ResourcePrinter which outputs an object as YAML. The input object is assumed to be in the internal version of an API and is converted to the given version first.

func (*YAMLPrinter) PrintObj 

func (p *YAMLPrinter) PrintObj(obj runtime.Object, w io.Writer) error

PrintObj prints the data as YAML.

Source Files

View all Source files

Directories

Path Synopsis
cmd
config
util
Package resource assists clients in dealing with RESTful objects that match the Kubernetes API conventions.
 Package resource assists clients in dealing with RESTful objects that match the Kubernetes API conventions.

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