39 lines
782 B
Go
39 lines
782 B
Go
package main
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import (
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"fmt"
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"io"
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"net/http"
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"os"
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"time"
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)
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func main() {
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start := time.Now()
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ch := make(chan string)
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for _, url := range os.Args[1:] {
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go fetch(url, ch) // start a goroutine
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}
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for range os.Args[1:] {
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fmt.Println(<-ch) // receive from channel ch
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}
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fmt.Printf("%.2fs elapsed\n", time.Since(start).Seconds())
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}
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func fetch(url string, ch chan<- string) {
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start := time.Now()
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resp, err := http.Get(url)
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if err != nil {
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ch <- fmt.Sprint(err) // send to channel ch
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return
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}
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defer resp.Body.Close() // don't leak resources
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nbytes, err := io.Copy(io.Discard, resp.Body)
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if err != nil {
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ch <- fmt.Sprintf("while reading %s: %v", url, err)
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return
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}
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secs := time.Since(start).Seconds()
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ch <- fmt.Sprintf("%.2fs %7d %s", secs, nbytes, url)
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}
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