Add RetryTimeout to configuration

Signed-off-by: Leandro López (inkel) <leandro.lopez@grafana.com>

Author: inkel

client.go

@@ -40,6 +40,8 @@ type Config struct {
 	OrgID int64
 	// NumRetries contains the number of attempted retries
 	NumRetries int
+	// RetryTimeout says how long to wait before retrying a request
+	RetryTimeout time.Duration
 }
 
 // New creates a new Grafana client.
@@ -93,7 +95,10 @@ func (c *Client) request(method, requestPath string, query url.Values, bodyRd io
 
 		// Wait a bit if that's not the first request
 		if n != 0 {
-			time.Sleep(time.Second * 5)
+			if c.config.RetryTimeout == 0 {
+				c.config.RetryTimeout = time.Second * 5
+			}
+			time.Sleep(c.config.RetryTimeout)
 		}
 
 		resp, err = c.client.Do(req)

client_test.go

@@ -9,6 +9,7 @@ import (
 	"net/http/httptest"
 	"net/url"
 	"testing"
+	"time"
 )
 
 func TestNew_basicAuth(t *testing.T) {
@@ -228,8 +229,9 @@ func TestClient_requestWithRetries(t *testing.T) {
 	}
 
 	c, err := New(ts.URL, Config{
-		NumRetries: 5,
-		Client:     httpClient,
+		NumRetries:   5,
+		Client:       httpClient,
+		RetryTimeout: 50 * time.Millisecond,
 	})
 	if err != nil {
 		t.Fatalf("unexpected error creating client: %v", err)