40 lines
706 B
Go
40 lines
706 B
Go
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package main
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import (
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"fmt"
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"net/http"
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"time"
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)
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var tenSecondTimeout = 10 * time.Second
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func Racer(a, b string) (winner string, err error) {
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return ConfigurableRacer(a, b, tenSecondTimeout)
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}
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func ConfigurableRacer(a, b string, timeout time.Duration) (winner string, err error) {
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select {
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case <-ping(a):
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return a, nil
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case <-ping(b):
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return b, nil
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case <-time.After(timeout):
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return "", fmt.Errorf("timed out waiting for %s and %s", a, b)
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}
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}
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func ping(url string) chan struct{} {
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ch := make(chan struct{})
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go func() {
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http.Get(url)
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close(ch)
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}()
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return ch
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}
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func measureResponseTime(url string) time.Duration {
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start := time.Now()
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http.Get(url)
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return time.Since(start)
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}
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