README
¶
go-window-io
A Sliding window over arbitrary io.Readers in go.
wio or windowed-io wraps an io.Reader and implements io.Read but reads data chunked over a Sliding Window.
wio provides two controls: window size and the step size.
For a canonical Rolling window, the step size is 1.
Examples
wSize := 3 // window size of 3
rollingBuf := []byte("\x00\x01\x02\x03\x04\x05\x06\x07\x08")
reader := bytes.NewBuffer(rollingBuf)
rollingReader := wio.NewRolling(reader, wSize)
// For a window that rolls by more than 1:
// sSize := 2 // window of 3 slide by 2
// steppingReader := wio.NewRolling(reader, wSize, sSize)
for {
// buf is some buffer at-least wSize in size
n, err := rollingReader.Read(buf)
if err != nil {
if err == io.EOF {
// handle EOF
}
if err == io.ErrShortBuffer {
// len of `buf` was shorter than wSize - make sure the given buf has correct size
}
}
// n can be less than wSize for the last window
consumeData(buf[:n])
}
Benchmarks:
• [MEASUREMENT]
Test window io
/Users/UrjitSingh/AdvancedApps/gocode/src/github.com/urjitbhatia/go-window-io/wio_test.go:19
benchmark rolling window
/Users/UrjitSingh/AdvancedApps/gocode/src/github.com/urjitbhatia/go-window-io/wio_test.go:199
Ran 1000 samples:
runtime:
Fastest Time: 0.002s
Slowest Time: 0.004s
Average Time: 0.003s ± 0.000s
------------------------------
Ran 12 of 12 Specs in 2.566 seconds
SUCCESS! -- 12 Passed | 0 Failed | 0 Pending | 0 Skipped --- PASS: TestGoWindowIo (2.57s)
goos: darwin
goarch: amd64
pkg: github.com/urjitbhatia/go-window-io
BenchmarkRollingWindow/BufSize:_10240_wSize:_1-8 50000000 31.3 ns/op 0 B/op 0 allocs/op
BenchmarkRollingWindow/BufSize:_10240_wSize:_103-8 50000000 33.4 ns/op 0 B/op 0 allocs/op
BenchmarkRollingWindow/BufSize:_10240_wSize:_205-8 50000000 31.3 ns/op 0 B/op 0 allocs/op
BenchmarkRollingWindow/BufSize:_10240_wSize:_307-8 50000000 32.6 ns/op 0 B/op 0 allocs/op
BenchmarkRollingWindow/BufSize:_10240_wSize:_409-8 50000000 31.7 ns/op 0 B/op 0 allocs/op
BenchmarkRollingWindow/BufSize:_10240_wSize:_511-8 50000000 33.0 ns/op 0 B/op 0 allocs/op
BenchmarkRollingWindow/BufSize:_10240_wSize:_613-8 50000000 32.7 ns/op 0 B/op 0 allocs/op
BenchmarkRollingWindow/BufSize:_10240_wSize:_715-8 50000000 33.1 ns/op 0 B/op 0 allocs/op
BenchmarkRollingWindow/BufSize:_10240_wSize:_817-8 50000000 30.6 ns/op 0 B/op 0 allocs/op
BenchmarkRollingWindow/BufSize:_10240_wSize:_919-8 50000000 33.2 ns/op 0 B/op 0 allocs/op
BenchmarkRollingWindow/BufSize:_10240_wSize:_1021-8 50000000 32.0 ns/op 0 B/op 0 allocs/op
BenchmarkRollingWindow/BufSize:_10240_wSize:_1123-8 30000000 33.4 ns/op 0 B/op 0 allocs/op
BenchmarkRollingWindow/BufSize:_10240_wSize:_1225-8 50000000 32.6 ns/op 0 B/op 0 allocs/op
BenchmarkRollingWindow/BufSize:_10240_wSize:_1327-8 50000000 32.9 ns/op 0 B/op 0 allocs/op
BenchmarkRollingWindow/BufSize:_10240_wSize:_1429-8 50000000 31.6 ns/op 0 B/op 0 allocs/op
BenchmarkRollingWindow/BufSize:_10240_wSize:_1531-8 50000000 33.2 ns/op 0 B/op 0 allocs/op
BenchmarkRollingWindow/BufSize:_10240_wSize:_1633-8 50000000 31.7 ns/op 0 B/op 0 allocs/op
BenchmarkRollingWindow/BufSize:_10240_wSize:_1735-8 50000000 31.9 ns/op 0 B/op 0 allocs/op
BenchmarkRollingWindow/BufSize:_10240_wSize:_1837-8 50000000 32.1 ns/op 0 B/op 0 allocs/op
BenchmarkRollingWindow/BufSize:_10240_wSize:_1939-8 50000000 33.3 ns/op 0 B/op 0 allocs/op
BenchmarkRollingWindow/BufSize:_10240_wSize:_2041-8 50000000 32.1 ns/op 0 B/op 0 allocs/op
PASS
ok github.com/urjitbhatia/go-window-io 44.603s
Documentation
¶
Index ¶
Constants ¶
This section is empty.
Variables ¶
View Source
var ErrDisjointWindow = errors.New("Step size cannot be larger than window size")
ErrDisjointWindow - Step size has to be >= 1 && <= window size
View Source
var ErrZeroStepSize = errors.New("Step size cannot be zero. Should be 1 or more")
ErrZeroStepSize - Step size has to be >= 1
View Source
var ErrZeroWindowSize = errors.New("Window size cannot be zero. Should be 1 or more")
ErrZeroWindowSize - Window size has to be >= 1
Functions ¶
Types ¶
type WindowReader ¶
WindowReader wraps io.Reader and reads in a window of data The window size and the window rolling step size can be configured
func NewRolling ¶
func NewRolling(r io.Reader, wSize int) (WindowReader, error)
NewRolling converts an io.Reader into a rolling windowed io.Reader The size of a Rolling Window is 1. This is same as calling: NewStepping(reader, w, 1)
func NewStepping ¶
func NewStepping(r io.Reader, wSize, sSize int) (WindowReader, error)
NewStepping converts an io.Reader into a windowed io.Reader with a window size of wSize, and a step size of sSize
Source Files
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