metadata

Documentation

Overview

Package metadata describes metadata paths stored in the cache per target.

Index

• Constants
• Variables
• func LatencyPath(w time.Duration, typ latency.StatType) []string
• func Path(value string) []string
• func RegisterIntValue(name string, val *IntValue)
• func RegisterLatencyMetadata(windowSizes []time.Duration)
• func RegisterServerNameMetadata()
• func RegisterStrValue(name string, val *StrValue)
• func UnregisterIntValue(name string)
• func UnregisterServerNameMetadata()
• func UnregisterStrValue(name string)
• type IntValue
• type Metadata
  • func New() *Metadata
  • func (m *Metadata) AddInt(value string, i int64) error
  • func (m *Metadata) Clear()
  • func (m *Metadata) GetBool(value string) (bool, error)
  • func (m *Metadata) GetInt(value string) (int64, error)
  • func (m *Metadata) GetStr(value string) (string, error)
  • func (m *Metadata) ResetEntry(entry string) error
  • func (m *Metadata) SetBool(value string, v bool) error
  • func (m *Metadata) SetInt(value string, v int64) error
  • func (m *Metadata) SetStr(value, v string) error
• type StrValue

Constants

const (
	// Root node where metadata is cached.
	Root = "meta"

	// Sync is a boolean that reports whether all target state is cached.
	Sync = "sync"
	// Connected is a boolean that reports whether updates are being received.
	Connected = "connected"
	// ConnectedAddr is a string denoting the last-hop IP address of a connected
	// target.
	ConnectedAddr = "connectedAddress"
	// AddCount is the total number of leaves that have been added.
	AddCount = "targetLeavesAdded"
	// DelCount is the total number of leaves that have been deleted.
	DelCount = "targetLeavesDeleted"
	// EmptyCount is the total number of notifications delivered that contain no
	// updates or deletes.
	EmptyCount = "targetLeavesEmpty"
	// LeafCount is the current total leaves stored in the cache.
	LeafCount = "targetLeaves"
	// UpdateCount is the total number of leaf updates received.
	UpdateCount = "targetLeavesUpdated"
	// StaleCount is the total number of leaf updates that had timestamp older
	// than that cached.
	StaleCount = "targetLeavesStale"
	// FutureCount is the total number of leaf updates that are rejected because
	// of having timestamp too far in the future.
	FutureCount = "targetLeavesFuture"
	// SuppressedCount is the total number of leaf updates that were suppressed
	// because the update had the same value as already cached.
	SuppressedCount = "targetLeavesSuppressed"
	// Size is the total number of bytes used to store all values.  This count
	// excludes all indexing overhead.
	Size = "targetSize"
	// LatestTimestamp is the latest timestamp for any update received for the
	// target.
	LatestTimestamp = "latestTimestamp"
	// ConnectError is the error related to connection failure.
	ConnectError = "connectError"
	// ServerName is an optional metadata used to identify the server to clients.
	ServerName = "serverName"
)

Variables

var (
	// TargetBoolValues is the list of all bool metadata fields.
	TargetBoolValues = map[string]bool{
		Sync:      true,
		Connected: true,
	}

	// TargetIntValues is the list of all int64 metadata fields.
	TargetIntValues = map[string]*IntValue{
		AddCount:        {[]string{Root, AddCount}, true},
		DelCount:        {[]string{Root, DelCount}, true},
		EmptyCount:      {[]string{Root, EmptyCount}, true},
		LeafCount:       {[]string{Root, LeafCount}, true},
		UpdateCount:     {[]string{Root, UpdateCount}, true},
		StaleCount:      {[]string{Root, StaleCount}, true},
		FutureCount:     {[]string{Root, FutureCount}, true},
		SuppressedCount: {[]string{Root, SuppressedCount}, true},
		Size:            {[]string{Root, Size}, true},
		LatestTimestamp: {[]string{Root, LatestTimestamp}, true},
	}

	// TargetStrValues is the list of all string metadata fields.
	TargetStrValues = map[string]*StrValue{
		ConnectedAddr: {InitEmptyStr: true},
		ConnectError:  {InitEmptyStr: false},
	}
)

var ErrInvalidValue = errors.New("invalid metadata value")

ErrInvalidValue is returned when a metadata operation is attempted on a value that does not exist.

var ErrUnsetValue = errors.New("unset value")

ErrUnsetValue is returned when a metadata Get is attempted on a value that has not been Set (or Added).

Functions

func LatencyPath

func LatencyPath(w time.Duration, typ latency.StatType) []string

LatencyPath returns the metadata path for the latency statistics of window w and type typ.

func Path

func Path(value string) []string

Path is a convenience function that will return the full metadata path for any valid metadata value. Only metadata values registered above in TargetBoolValues, TargetIntValues, and TargetStrValues will return a path. An invalid metadata value will return nil.

func RegisterIntValue

func RegisterIntValue(name string, val *IntValue)

RegisterIntValue registers an int64 type metadata whose path and options are in val.

func RegisterLatencyMetadata

func RegisterLatencyMetadata(windowSizes []time.Duration)

RegisterLatencyMetadata registers latency stats metadata for time windows specified in windowSizes. RegisterLatencyMetadata is not thread-safe and should be called before any metadata.Metadata is instantiated.

func RegisterServerNameMetadata

func RegisterServerNameMetadata()

RegisterServerNameMetadata registers the serverName metadata.

func RegisterStrValue

func RegisterStrValue(name string, val *StrValue)

RegisterStrValue registers a string type metadata.

func UnregisterIntValue

func UnregisterIntValue(name string)

UnregisterIntValue unregisters an int64 type metadata name.

func UnregisterServerNameMetadata

func UnregisterServerNameMetadata()

UnregisterServerNameMetadata registers the serverName metadata.

func UnregisterStrValue

func UnregisterStrValue(name string)

UnregisterStrValue unregisters a string type metadata.

Types

type IntValue

type IntValue struct {
	Path     []string // Path of the int64 metadata
	InitZero bool     // Whether to initiate to 0 (for counters starting from 0).
}

IntValue contains the path and other options for an int64 metadata.

type Metadata

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

Metadata is the container for all target specific metadata.

func New

func New() *Metadata

New returns an initialized Metadata structure. Integer values are initialized to 0. Boolean values are initialized to false. String values are initialized to empty string.

func (*Metadata) AddInt

func (m *Metadata) AddInt(value string, i int64) error

AddInt atomically increments the metadata value specified by i.

func (*Metadata) Clear

func (m *Metadata) Clear()

Clear sets all metadata values to zero values, except that ConnectError is set to EmptyError.

func (*Metadata) GetBool

func (m *Metadata) GetBool(value string) (bool, error)

GetBool atomically retrieves the metadata value specified.

func (*Metadata) GetInt

func (m *Metadata) GetInt(value string) (int64, error)

GetInt atomically retrieves the metadata value specified.

func (*Metadata) GetStr

func (m *Metadata) GetStr(value string) (string, error)

GetStr atomically retrieves the metadata value specified.

func (*Metadata) ResetEntry

func (m *Metadata) ResetEntry(entry string) error

ResetEntry resets metadata entry to zero value. It will be deleted if it is Int with InitZero as false, or Str with InitEmptyStr as false.

func (*Metadata) SetBool

func (m *Metadata) SetBool(value string, v bool) error

SetBool atomically sets the metadata value specified to v.

func (*Metadata) SetInt

func (m *Metadata) SetInt(value string, v int64) error

SetInt atomically sets the metadata value specified to v.

func (*Metadata) SetStr

func (m *Metadata) SetStr(value, v string) error

SetStr atomically sets the metadata value specified to v.

type StrValue

type StrValue struct {
	InitEmptyStr bool // Whether to initiate to "".
}

StrValue contains the valid and the option to reset to emptry string.