No way to know how many retries were done, which can be helpful for monitoring

[diaasami]

One solution would be to add a hook that is called on success (with number of retries done), and failure (also with number of retries), this can be helpful for anyone who wants to monitor how many retries are being done and monitoring their infrastructure.

Is there a way to do this currently?

[SimonRichardson]

You could pass in a request ID into the context and then just record it in the retry logic.

client := retryablehttp.NewClient()
client.CheckRetry = (ctx context.Context, resp *http.Response, err error) (bool, error) {
	metric.WithLabels(RequestID(ctx), resp.Request.URL).Inc()

	return retryablehttp.DefaultRetryPolicy(ctx, resp, err)
}
func RequestID(ctx context.Context) string {
	 id, ok := ctx.Value(contextKeyRequestID).(string)
	 if !ok {
	 	 return "unknown"
	 }
	 return id
}
ctx := context.WithContext(ctx), contextKeyRequestID, "aaa")
req, _ := http.NewRequestWithContext(ctx, "GET", "http:https://localhost:8080", nil)
resp, err := client.Do(req)