README
¶
iothrottler
A Go package for throttling application IO (such as bandwidth).
Installation
If you have the Go Language installed type
go get "github.com/efarrer/iothrottler"
Example
import (
"bytes"
"fmt"
"io"
"github.com/efarrer/iothrottler"
"os"
)
// Basic usage of a IOThrottlerPool to throttle reading from a file
func ExampleIOThrottlerPool() {
// Construct a bandwidth throttling pool that's limited to 100 bytes per second
pool := iothrottler.NewIOThrottlerPool(iothrottler.BytesPerSecond * 100)
defer pool.ReleasePool()
file, err := os.Open("/dev/zero")
if err != nil {
// handle error
return
}
defer file.Close()
throttledFile, err := pool.AddReader(file)
if err != nil {
// handle error
return
}
var zeros bytes.Buffer
copied, err := io.CopyN(&zeros, throttledFile, 200)
if err != nil {
// handle error
}
fmt.Printf("Copied %v bytes\n", copied)
// Output: Copied 200 bytes
}
Documentation
¶
Index ¶
- Constants
- type Bandwidth
- type IOThrottlerPool
- func (p *IOThrottlerPool) AddConn(conn net.Conn) (net.Conn, error)
- func (p *IOThrottlerPool) AddReadWriter(readWriter io.ReadWriteCloser) (io.ReadWriteCloser, error)
- func (p *IOThrottlerPool) AddReader(reader io.ReadCloser) (io.ReadCloser, error)
- func (p *IOThrottlerPool) AddWriter(writer io.WriteCloser) (io.WriteCloser, error)
- func (pool *IOThrottlerPool) ReleasePool()
- func (pool *IOThrottlerPool) SetBandwidth(bandwith Bandwidth)
Examples ¶
Constants ¶
const ( // Bytes per second BytesPerSecond Bandwidth = 1 // Kilobits per second Kbps = BytesPerSecond * (1024 / 8) // Megabits per second Mbps = Kbps * 1024 // Gigabits per second Gbps = Mbps * 1024 // Unlimited bandwidth Unlimited = math.MaxInt64 )
Variables ¶
This section is empty.
Functions ¶
This section is empty.
Types ¶
type Bandwidth ¶
type Bandwidth int64
The Bandwidth type represents a bandwidth quantity in bytes per second. Sub-byte per seconds values are not supported
type IOThrottlerPool ¶
type IOThrottlerPool struct {
// contains filtered or unexported fields
}
A pool for throttling IO
Example ¶
Basic usage of a IOThrottlerPool to throttle reading from a file
package main
import (
"bytes"
"fmt"
"io"
"os"
"github.com/efarrer/iothrottler"
)
func main() {
// Construct a bandwidth throttling pool that's limited to 100 bytes per second
pool := iothrottler.NewIOThrottlerPool(iothrottler.BytesPerSecond * 100)
defer pool.ReleasePool()
file, err := os.Open("/dev/zero")
if err != nil {
// handle error
return
}
defer file.Close()
throttledFile, err := pool.AddReader(file)
if err != nil {
// handle error
return
}
var zeros bytes.Buffer
copied, err := io.CopyN(&zeros, throttledFile, 200)
if err != nil {
// handle error
}
fmt.Printf("Copied %v bytes\n", copied)
}
Output: Copied 200 bytes
func NewIOThrottlerPool ¶
func NewIOThrottlerPool(bandwidth Bandwidth) *IOThrottlerPool
Construct a new IO throttling pool The bandwidth for this pool will be limited to 'bandwidth'
func (*IOThrottlerPool) AddConn ¶
Restrict the network connection to the bandwidth limitations of the IOThrottlerPool
Example ¶
Throttle web requests using an IOThrottlerPool
package main
import (
"fmt"
"io/ioutil"
"net"
"net/http"
"github.com/efarrer/iothrottler"
)
func main() {
// Construct a bandwidth throttling pool that's limited to 30 kilobits per
// second
pool := iothrottler.NewIOThrottlerPool(iothrottler.Kbps * 30)
defer pool.ReleasePool()
// Create our own Dial function that will be used for the http connection
throttledDial := func(nt, addr string) (c net.Conn, err error) {
conn, err := net.Dial(nt, addr)
if err != nil {
return nil, err
}
return pool.AddConn(conn)
}
// Create a transport that will use our throttled Dial function
tr := &http.Transport{
Proxy: http.ProxyFromEnvironment,
Dial: throttledDial,
}
// Download the page
client := &http.Client{Transport: tr}
resp, err := client.Get("http://www.google.com")
if err != nil {
// handle error
return
}
defer resp.Body.Close()
// Read the entire contents of the body
_, err = ioutil.ReadAll(resp.Body)
if err != nil {
// handle error
return
}
fmt.Println("Downloaded www.google.com")
}
Output: Downloaded www.google.com
func (*IOThrottlerPool) AddReadWriter ¶
func (p *IOThrottlerPool) AddReadWriter(readWriter io.ReadWriteCloser) (io.ReadWriteCloser, error)
Add a io.ReadWriteCloser to the pool. The returned io.ReadWriteCloser shares the IOThrottlerPool's bandwidth with other items in the pool.
func (*IOThrottlerPool) AddReader ¶
func (p *IOThrottlerPool) AddReader(reader io.ReadCloser) (io.ReadCloser, error)
Add a io.ReadCloser to the pool. The returned io.ReadCloser shares the IOThrottlerPool's bandwidth with other items in the pool.
func (*IOThrottlerPool) AddWriter ¶
func (p *IOThrottlerPool) AddWriter(writer io.WriteCloser) (io.WriteCloser, error)
Add a io.WriteCloser to the pool. The returned io.WriteCloser shares the IOThrottlerPool's bandwidth with other items in the pool.
func (*IOThrottlerPool) ReleasePool ¶
func (pool *IOThrottlerPool) ReleasePool()
Release the IOThrottlerPool all bandwidth
func (*IOThrottlerPool) SetBandwidth ¶
func (pool *IOThrottlerPool) SetBandwidth(bandwith Bandwidth)
Sets the IOThrottlerPool's bandwith rate
Source Files