limiter

Documentation

Overview

Package limiter provides concurrency limiters.

Index

• type Fixed
  • func NewFixed(limit int) Fixed
  • func (t Fixed) Available() int
  • func (t Fixed) Capacity() int
  • func (t Fixed) Idle() bool
  • func (t Fixed) Release()
  • func (t Fixed) Take()
  • func (t Fixed) TryTake() bool
• type Rate
  • func NewRate(bytesPerSec, burstLimit int) Rate
• type Writer
  • func NewWriter(w io.WriteCloser, bytesPerSec, burstLimit int) *Writer
  • func NewWriterWithRate(w io.WriteCloser, limiter Rate) *Writer
  • func (s *Writer) Close() error
  • func (s *Writer) Name() string
  • func (s *Writer) Sync() error
  • func (s *Writer) Write(b []byte) (int, error)

Types

type Fixed

type Fixed chan struct{}

Fixed is a simple channel-based concurrency limiter. It uses a fixed size channel to limit callers from proceeding until there is a value available in the channel. If all are in-use, the caller blocks until one is freed.

func NewFixed

func NewFixed(limit int) Fixed

func (Fixed) Available

func (t Fixed) Available() int

Available returns the number of available tokens that may be taken.

func (Fixed) Capacity

func (t Fixed) Capacity() int

Capacity returns the number of tokens can be taken.

func (Fixed) Idle

func (t Fixed) Idle() bool

Idle returns true if the limiter has all its capacity is available.

func (Fixed) Release

func (t Fixed) Release()

Release releases a token back to the limiter.

func (Fixed) Take

func (t Fixed) Take()

Take attempts to take a token and blocks until one is available.

func (Fixed) TryTake

func (t Fixed) TryTake() bool

TryTake attempts to take a token and return true if successful, otherwise returns false.

type Rate

type Rate interface {
	WaitN(ctx context.Context, n int) error
	Burst() int
}

func NewRate

func NewRate(bytesPerSec, burstLimit int) Rate

type Writer

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

func NewWriter

func NewWriter(w io.WriteCloser, bytesPerSec, burstLimit int) *Writer

NewWriter returns a writer that implements io.Writer with rate limiting. The limiter use a token bucket approach and limits the rate to bytesPerSec with a maximum burst of burstLimit.

func NewWriterWithRate

func NewWriterWithRate(w io.WriteCloser, limiter Rate) *Writer

WithRate returns a Writer with the specified rate limiter.

func (*Writer) Close

func (s *Writer) Close() error

func (*Writer) Name

func (s *Writer) Name() string

func (*Writer) Sync

func (s *Writer) Sync() error

func (*Writer) Write

func (s *Writer) Write(b []byte) (int, error)

Write writes bytes from b.