From bef482fd68ce4d5fb1be49def45dbe044897e60b Mon Sep 17 00:00:00 2001
From: Philipp Wolfer <ph.wolfer@gmail.com>
Date: Mon, 13 Nov 2023 18:20:01 +0100
Subject: [PATCH] Funkwhale: Handle rate limit headers

---
 backends/funkwhale/client.go | 32 +++++++++++++++++++++++---------
 1 file changed, 23 insertions(+), 9 deletions(-)

diff --git a/backends/funkwhale/client.go b/backends/funkwhale/client.go
index c3d8f51..c178981 100644
--- a/backends/funkwhale/client.go
+++ b/backends/funkwhale/client.go
@@ -23,7 +23,9 @@ package funkwhale
 
 import (
 	"errors"
+	"net/http"
 	"strconv"
+	"time"
 
 	"github.com/go-resty/resty/v2"
 )
@@ -36,17 +38,29 @@ type Client struct {
 }
 
 func NewClient(serverUrl string, token string) Client {
-	resty := resty.New()
-	resty.SetBaseURL(serverUrl)
-	resty.SetAuthScheme("Bearer")
-	resty.SetAuthToken(token)
-	resty.SetHeader("Accept", "application/json")
-	client := Client{
-		HttpClient: resty,
+	client := resty.New()
+	client.SetBaseURL(serverUrl)
+	client.SetAuthScheme("Bearer")
+	client.SetAuthToken(token)
+	client.SetHeader("Accept", "application/json")
+
+	// Handle rate limiting (see https://docs.funkwhale.audio/developer/api/rate-limit.html)
+	client.SetRetryCount(5)
+	client.AddRetryCondition(
+		func(r *resty.Response, err error) bool {
+			return r.StatusCode() == http.StatusTooManyRequests
+		},
+	)
+	client.SetRetryMaxWaitTime(time.Duration(1 * time.Minute))
+	client.SetRetryAfter(func(client *resty.Client, resp *resty.Response) (time.Duration, error) {
+		retryAfter, err := strconv.Atoi(resp.Header().Get("X-RateLimit-Reset-In"))
+		return time.Duration(retryAfter * int(time.Second)), err
+	})
+
+	return Client{
+		HttpClient: client,
 		token:      token,
 	}
-
-	return client
 }
 
 func (c Client) GetHistoryListenings(user string, page int, perPage int) (result ListeningsResult, err error) {