ratelimit

package
v0.3.5 Latest Latest
Warning

This package is not in the latest version of its module.

Go to latest
Published: Jun 12, 2015 License: MIT, MIT Imports: 1 Imported by: 3

README

goprocess/ratelimit - ratelimit children creation

Documentation

Overview

Package ratelimit is part of github.com/jbenet/goprocess. It provides a simple process that ratelimits child creation. This is done internally with a channel/semaphore. So the call `RateLimiter.LimitedGo` may block until another child is Closed().

Index

Constants

This section is empty.

Variables

This section is empty.

Functions

func LimitChan

func LimitChan(limit int) chan struct{}

LimitChan returns a rate-limiting channel. it is the usual, simple, golang-idiomatic rate-limiting semaphore. This function merely initializes it with certain buffer size, and sends that many values, so it is ready to be used.

Types

type RateLimiter

type RateLimiter struct {
	process.Process
	// contains filtered or unexported fields
}

RateLimiter limits the spawning of children. It does so with an internal semaphore. Note that Go will continue to be the unlimited process.Process.Go, and ONLY the added function `RateLimiter.LimitedGo` will honor the limit. This is to improve readability and avoid confusion for the reader, particularly if code changes over time.

func NewRateLimiter

func NewRateLimiter(parent process.Process, limit int) *RateLimiter

func (*RateLimiter) LimitedGo

func (rl *RateLimiter) LimitedGo(f process.ProcessFunc)

LimitedGo creates a new process, adds it as a child, and spawns the ProcessFunc f in its own goroutine, but may block according to the internal rate limit. It is equivalent to:

func(f process.ProcessFunc) {
   <-limitch
   p.Go(func (child process.Process) {
     f(child)
     f.Close() // make sure its children close too!
     limitch<- struct{}{}
   })

/ }

It is useful to construct simple asynchronous workers, children of p, and rate limit their creation, to avoid spinning up too many, too fast. This is great for providing backpressure to producers.

Jump to

Keyboard shortcuts

? : This menu
/ : Search site
f or F : Jump to
y or Y : Canonical URL