fix: use RateLimitBackoff client in LD API (#437)

#434 attempted to
handle the rate limit from the LD API but the LD API client uses
`http.DefaultClient` by default. This change passes in the client with
`RateLimitBackoff` set into the call to init the LD API client.

Author: jonathan-ostrander

internal/ld/ld.go

@@ -85,6 +85,7 @@ func RateLimitBackoff(now func() time.Time, fallbackBackoff h.Backoff) func(time
 				if s, ok := resp.Header["X-Ratelimit-Reset"]; ok {
 					if sleepUntil, err := strconv.ParseInt(s[0], 10, 64); err == nil {
 						sleep := sleepUntil - now().UnixMilli()
+						log.Info.Printf("rate limit for %s %s hit, sleeping for %d ms", resp.Request.Method, resp.Request.URL, sleep)
 
 						if sleep > 0 {
 							return time.Millisecond * time.Duration(sleep)
@@ -113,7 +114,8 @@ func InitApiClient(options ApiOptions) ApiClient {
 
 	return ApiClient{
 		ldClient: ldapi.NewAPIClient(&ldapi.Configuration{
-			UserAgent: options.UserAgent,
+			HTTPClient: client.StandardClient(),
+			UserAgent:  options.UserAgent,
 			Servers: []ldapi.ServerConfiguration{{
 				URL: options.BaseUri,
 			}},

internal/ld/ld_test.go

@@ -3,6 +3,7 @@ package ld
 import (
 	"net/http"
 	"net/http/httptest"
+	"net/url"
 	"os"
 	"testing"
 	"time"
@@ -260,9 +261,15 @@ func TestRateLimitBackoff(t *testing.T) {
 	}
 	for _, tt := range specs {
 		t.Run(tt.name, func(t *testing.T) {
+			testUrl, _ := url.Parse("http://test.example/")
+			req := &http.Request{
+				Method: "POST",
+				URL:    testUrl,
+			}
 			resp := &http.Response{
 				StatusCode: tt.status,
 				Header:     make(http.Header),
+				Request:    req,
 			}
 
 			if tt.rateLimitReset != nil {