metric

Documentation

Index

• func Avg(iterator Iterator) float64
• func Count(iterator Iterator) float64
• func Max(iterator Iterator) float64
• func Min(iterator Iterator) float64
• func Sum(iterator Iterator) float64
• type Aggregation
• type Bucket
  • func (b *Bucket) Add(offset int, val float64)
  • func (b *Bucket) Append(val float64)
  • func (b *Bucket) Next() *Bucket
  • func (b *Bucket) Reset()
• type Counter
  • func NewCounter(opts CounterOpts) Counter
• type CounterOpts
• type Gauge
  • func NewGauge(opts GaugeOpts) Gauge
• type GaugeOpts
• type Iterator
  • func (i *Iterator) Bucket() Bucket
  • func (i *Iterator) Next() bool
• type Metric
• type Opts
• type PointGauge
  • func NewPointGauge(opts PointGaugeOpts) PointGauge
• type PointGaugeOpts
• type PointPolicy
  • func NewPointPolicy(window *Window) *PointPolicy
  • func (p *PointPolicy) Append(val float64)
  • func (p *PointPolicy) Reduce(f func(Iterator) float64) float64
• type RollingCounter
  • func NewRollingCounter(opts RollingCounterOpts) RollingCounter
• type RollingCounterOpts
• type RollingGauge
  • func NewRollingGauge(opts RollingGaugeOpts) RollingGauge
• type RollingGaugeOpts
• type RollingPolicy
  • func NewRollingPolicy(window *Window, opts RollingPolicyOpts) *RollingPolicy
  • func (r *RollingPolicy) Add(val float64)
  • func (r *RollingPolicy) Append(val float64)
  • func (r *RollingPolicy) Reduce(f func(Iterator) float64) (val float64)
• type RollingPolicyOpts
• type Window
  • func NewWindow(opts WindowOpts) *Window
  • func (w *Window) Add(offset int, val float64)
  • func (w *Window) Append(offset int, val float64)
  • func (w *Window) Bucket(offset int) Bucket
  • func (w *Window) Iterator(offset int, count int) Iterator
  • func (w *Window) ResetBucket(offset int)
  • func (w *Window) ResetBuckets(offsets []int)
  • func (w *Window) ResetWindow()
  • func (w *Window) Size() int
• type WindowOpts

Functions

func Avg

func Avg(iterator Iterator) float64

Avg the values within the window.

func Count

func Count(iterator Iterator) float64

Count sums the count value within the window.

func Max

func Max(iterator Iterator) float64

Max the values within the window.

func Min

func Min(iterator Iterator) float64

Min the values within the window.

func Sum

func Sum(iterator Iterator) float64

Sum the values within the window.

Types

type Aggregation

type Aggregation interface {
	// Min finds the min value within the window.
	Min() float64
	// Max finds the max value within the window.
	Max() float64
	// Avg computes average value within the window.
	Avg() float64
	// Sum computes sum value within the window.
	Sum() float64
}

Aggregation contains some common aggregation function. Each aggregation can compute summary statistics of window.

type Bucket

type Bucket struct {
	Points []float64
	Count  int64
	// contains filtered or unexported fields
}

Bucket contains multiple float64 points.

func (*Bucket) Add

func (b *Bucket) Add(offset int, val float64)

Add adds the given value to the point.

func (*Bucket) Append

func (b *Bucket) Append(val float64)

Append appends the given value to the bucket.

func (*Bucket) Next

func (b *Bucket) Next() *Bucket

Next returns the next bucket.

func (*Bucket) Reset

func (b *Bucket) Reset()

Reset empties the bucket.

type Counter

type Counter interface {
	Metric
}

Counter stores a numerical value that only ever goes up.

func NewCounter

func NewCounter(opts CounterOpts) Counter

NewCounter creates a new Counter based on the CounterOpts.

type CounterOpts

type CounterOpts Opts

CounterOpts is an alias of Opts.

type Gauge

type Gauge interface {
	Metric
	// Sets sets the value to the given number.
	Set(int64)
}

Gauge stores a numerical value that can be add arbitrarily.

func NewGauge

func NewGauge(opts GaugeOpts) Gauge

NewGauge creates a new Gauge based on the GaugeOpts.

type GaugeOpts

type GaugeOpts Opts

GaugeOpts is an alias of Opts.

type Iterator

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

Iterator iterates the buckets within the window.

func (*Iterator) Bucket

func (i *Iterator) Bucket() Bucket

Bucket gets current bucket.

func (*Iterator) Next

func (i *Iterator) Next() bool

Next returns true util all of the buckets has been iterated.

type Metric

type Metric interface {
	// Add adds the given value to the counter.
	Add(int64)
	// Value gets the current value.
	// If the metric's type is PointGauge, RollingCounter, RollingGauge,
	// it returns the sum value within the window.
	Value() int64
}

Metric is a sample interface. Implementations of Metrics in metric package are Counter, Gauge, PointGauge, RollingCounter and RollingGauge.

type Opts

type Opts struct {
}

Opts contains the common arguments for creating Metric.

type PointGauge

type PointGauge interface {
	Aggregation
	Metric
	// Reduce applies the reduction function to all buckets within the window.
	Reduce(func(Iterator) float64) float64
}

PointGauge represents a ring window. Every buckets within the window contains one point. When the window is full, the earliest point will be overwrite.

func NewPointGauge

func NewPointGauge(opts PointGaugeOpts) PointGauge

NewPointGauge creates a new PointGauge based on PointGaugeOpts.

type PointGaugeOpts

type PointGaugeOpts struct {
	// Size represents the bucket size within the window.
	Size int
}

PointGaugeOpts contains the arguments for creating PointGauge.

type PointPolicy

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

PointPolicy is a policy of points within the window. PointPolicy wraps the window and make it seem like ring-buf. When using PointPolicy, every buckets within the windows contains at more one point. e.g. [[1], [2], [3]]

func NewPointPolicy

func NewPointPolicy(window *Window) *PointPolicy

NewPointPolicy creates a new PointPolicy.

func (*PointPolicy) Append

func (p *PointPolicy) Append(val float64)

Append appends the given points to the window.

func (*PointPolicy) Reduce

func (p *PointPolicy) Reduce(f func(Iterator) float64) float64

Reduce applies the reduction function to all buckets within the window.

type RollingCounter

type RollingCounter interface {
	Metric
	Aggregation
	// Reduce applies the reduction function to all buckets within the window.
	Reduce(func(Iterator) float64) float64
}

RollingCounter represents a ring window based on time duration. e.g. [[1], [3], [5]]

func NewRollingCounter

func NewRollingCounter(opts RollingCounterOpts) RollingCounter

NewRollingCounter creates a new RollingCounter bases on RollingCounterOpts.

type RollingCounterOpts

type RollingCounterOpts struct {
	Size           int
	BucketDuration time.Duration
}

RollingCounterOpts contains the arguments for creating RollingCounter.

type RollingGauge

type RollingGauge interface {
	Metric
	Aggregation
	// Reduce applies the reduction function to all buckets within the window.
	Reduce(func(Iterator) float64) float64
}

RollingGauge represents a ring window based on time duration. e.g. [[1, 2], [1, 2, 3], [1,2, 3, 4]]

func NewRollingGauge

func NewRollingGauge(opts RollingGaugeOpts) RollingGauge

NewRollingGauge creates a new RollingGauge baseed on RollingGaugeOpts.

type RollingGaugeOpts

type RollingGaugeOpts struct {
	Size           int
	BucketDuration time.Duration
}

RollingGaugeOpts contains the arguments for creating RollingGauge.

type RollingPolicy

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

RollingPolicy is a policy for ring window based on time duration. RollingPolicy moves bucket offset with time duration. e.g. If the last point is appended one bucket duration ago, RollingPolicy will increment current offset.

func NewRollingPolicy

func NewRollingPolicy(window *Window, opts RollingPolicyOpts) *RollingPolicy

NewRollingPolicy creates a new RollingPolicy based on the given window and RollingPolicyOpts.

func (*RollingPolicy) Add

func (r *RollingPolicy) Add(val float64)

Add adds the given value to the latest point within bucket.

func (*RollingPolicy) Append

func (r *RollingPolicy) Append(val float64)

Append appends the given points to the window.

func (*RollingPolicy) Reduce

func (r *RollingPolicy) Reduce(f func(Iterator) float64) (val float64)

Reduce applies the reduction function to all buckets within the window.

type RollingPolicyOpts

type RollingPolicyOpts struct {
	BucketDuration time.Duration
}

RollingPolicyOpts contains the arguments for creating RollingPolicy.

type Window

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

Window contains multiple buckets.

func NewWindow

func NewWindow(opts WindowOpts) *Window

NewWindow creates a new Window based on WindowOpts.

func (*Window) Add

func (w *Window) Add(offset int, val float64)

Add adds the given value to the latest point within bucket where index equals the given offset.

func (*Window) Append

func (w *Window) Append(offset int, val float64)

Append appends the given value to the bucket where index equals the given offset.

func (*Window) Bucket

func (w *Window) Bucket(offset int) Bucket

Bucket returns the bucket where index equals the given offset.

func (*Window) Iterator

func (w *Window) Iterator(offset int, count int) Iterator

Iterator returns the bucket iterator.

func (*Window) ResetBucket

func (w *Window) ResetBucket(offset int)

ResetBucket empties the bucket based on the given offset.

func (*Window) ResetBuckets

func (w *Window) ResetBuckets(offsets []int)

ResetBuckets empties the buckets based on the given offsets.

func (*Window) ResetWindow

func (w *Window) ResetWindow()

ResetWindow empties all buckets within the window.

func (*Window) Size

func (w *Window) Size() int

Size returns the size of the window.

type WindowOpts

type WindowOpts struct {
	Size int
}

WindowOpts contains the arguments for creating Window.