68 lines
1.0 KiB
Go
68 lines
1.0 KiB
Go
package main
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import (
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"compress/gzip"
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"fmt"
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"io"
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"os"
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"sync"
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)
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/*
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@Ref: https://livebook.manning.com/book/go-in-practice/chapter-3/65
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1. Practice gzip compress
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2. How to use wait group
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3. os.Args[1:] can stream in multiple files to the program without writing a walk function. Command: go run main.go ./testdata/*
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*/
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func main() {
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// Single thread
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// for _, file := range os.Args[1:] {
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// err := compress(file)
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// if err != nil {
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// os.Exit(0)
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// }
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// }
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// Multi threads
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wg := sync.WaitGroup{}
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var (
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i int
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file string
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)
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for i, file = range os.Args[1:] {
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wg.Add(1)
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go func(filename string) {
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compress(filename)
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wg.Done()
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}(file)
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}
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wg.Wait()
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fmt.Printf("Compressed %d files\n", i+1)
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}
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func compress(filename string) error {
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in, err := os.Open(filename)
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if err != nil {
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return err
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}
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defer in.Close()
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out, err := os.Create(filename + ".gz")
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if err != nil {
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return err
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}
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defer out.Close()
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gzout := gzip.NewWriter(out)
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_, err = io.Copy(gzout, in)
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gzout.Close()
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return err
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}
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