59 lines
1.4 KiB
Go
59 lines
1.4 KiB
Go
package main
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import (
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"context"
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"errors"
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"fmt"
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"net/http"
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"strconv"
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"github.com/cenkalti/backoff/v5"
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)
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func ExampleRetry() {
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// Define an operation function that returns a value and an error.
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// The value can be any type.
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// We'll pass this operation to Retry function.
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operation := func() (string, error) {
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// An example request that may fail.
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resp, err := http.Get("http://httpbin.org/get")
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if err != nil {
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return "", err
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}
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defer resp.Body.Close()
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// If we are being rate limited, return a RetryAfter to specify how long to wait.
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// This will also reset the backoff policy.
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if resp.StatusCode == 429 {
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seconds, err := strconv.ParseInt(resp.Header.Get("Retry-After"), 10, 64)
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if err == nil {
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return "", backoff.RetryAfter(int(seconds))
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}
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}
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// In case of non-retriable error, return Permanent error to stop retrying.
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// For this HTTP example, client errors are non-retriable.
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if resp.StatusCode >= 400 && resp.StatusCode < 500 {
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return "", backoff.Permanent(errors.New("bad request"))
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}
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// Return successful response.
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return "hello", nil
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}
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result, err := backoff.Retry(context.TODO(), operation, backoff.WithBackOff(backoff.NewExponentialBackOff()))
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if err != nil {
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fmt.Println("Error:", err)
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return
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}
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// Operation is successful after retries.
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fmt.Println(result)
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// Output: hello
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}
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func main() {
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ExampleRetry()
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}
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