progress

README

progress

This library instruments io.Reader/io.Writer with progress printer.

Usage

See catp for an example.

var pr = &progress.Progress{
	Interval: 5 * time.Second,
	Print: func(status progress.ProgressStatus) {
		println(Status(status))
	},
}

func cat(filename string) {
	file, err := os.Open(filename)
	if err != nil {
		log.Fatal(err)
	}
	defer file.Close()

	st, err := file.Stat()
	if err != nil {
		log.Fatalf("failed to read file stats %s: %s", filename, err)
	}

	cr := &progress.CountingReader{Reader: file}

	pr.Start(st.Size, cr.Bytes, cr.Lines, filename)
	defer pr.Stop()

	readFile(cr)
}

Documentation

Overview

Package progress provides helpers to print progress status.

Index

• Constants
• func DefaultStatus(s Status) string
• func MetricsStatus(s Status) string
• type CountingReader
  • func (cr *CountingReader) Bytes() int64
  • func (cr *CountingReader) Lines() int64
  • func (cr *CountingReader) Read(p []byte) (n int, err error)
• type CountingWriter
  • func (cr *CountingWriter) Bytes() int64
  • func (cr *CountingWriter) Lines() int64
  • func (cr *CountingWriter) Write(p []byte) (n int, err error)
• type Metric
• type MetricsExposer
• type Progress
  • func (p *Progress) AddMetrics(metrics ...Metric)
  • func (p *Progress) Lines() int64
  • func (p *Progress) Start(options ...func(t *Task))
  • func (p *Progress) Stop()
• type Status
• type Task
• type Type

Constants

const (
	Bytes    = Type("bytes")
	Duration = Type("duration")
	Gauge    = Type("gauge")
)

Type values.

Functions

func DefaultStatus

func DefaultStatus(s Status) string

DefaultStatus renders Status as a string.

func MetricsStatus

func MetricsStatus(s Status) string

MetricsStatus renders Status metrics as a string.

Types

type CountingReader

type CountingReader struct {
	Reader io.Reader
	// contains filtered or unexported fields
}

CountingReader wraps io.Reader to count bytes.

func (*CountingReader) Bytes

func (cr *CountingReader) Bytes() int64

Bytes returns number of read bytes.

func (*CountingReader) Lines

func (cr *CountingReader) Lines() int64

Lines returns number of read lines.

func (*CountingReader) Read

func (cr *CountingReader) Read(p []byte) (n int, err error)

Read reads and counts bytes.

type CountingWriter

type CountingWriter struct {
	Writer io.Writer
	// contains filtered or unexported fields
}

CountingWriter wraps io.Writer to count bytes.

func (*CountingWriter) Bytes

func (cr *CountingWriter) Bytes() int64

Bytes returns number of written bytes.

func (*CountingWriter) Lines

func (cr *CountingWriter) Lines() int64

Lines returns number of written bytes.

func (*CountingWriter) Write

func (cr *CountingWriter) Write(p []byte) (n int, err error)

Write writes and counts bytes.

type Metric

type Metric struct {
	Name  string
	Type  Type
	Value func() int64
}

Metric is an operation metric.

type MetricsExposer

type MetricsExposer interface {
	Metrics() []Metric
}

MetricsExposer provides metric counters.

type Progress

type Progress struct {
	Interval       time.Duration
	Print          func(status Status)
	ShowHeapStats  bool
	ShowLinesStats bool
	// contains filtered or unexported fields
}

Progress reports reading performance.

func (*Progress) AddMetrics

func (p *Progress) AddMetrics(metrics ...Metric)

AddMetrics adds more metrics to progress status message.

func (*Progress) Lines

func (p *Progress) Lines() int64

Lines returns current number of lines.

func (*Progress) Start

func (p *Progress) Start(options ...func(t *Task))

Start spawns background progress reporter.

func (*Progress) Stop

func (p *Progress) Stop()

Stop stops progress reporting.

type Status

type Status struct {
	Task           string
	DonePercent    float64
	LinesCompleted int64
	SpeedMBPS      float64
	SpeedLPS       float64
	Elapsed        time.Duration
	Remaining      time.Duration
	Metrics        []Metric
}

Status describes current progress.

type Task

type Task struct {
	TotalBytes   func() int64
	CurrentBytes func() int64
	CurrentLines func() int64
	Task         string
	Continue     bool
}

Task describes a long-running process.

type Type

type Type string

Type describes metric value.