API: Potential rate limit fix for reactions

api/rate/rate.go

@@ -31,8 +31,10 @@ type Limiter struct {
 
 	Prefix string
 
-	global  *int64 // atomic guarded, unixnano
-	buckets sync.Map
+	global int64 // atomic guarded, unixnano
+
+	bucketMu sync.Mutex
+	buckets  map[string]*bucket
 }
 
 type CustomRateLimit struct {
@@ -60,8 +62,7 @@ func newBucket() *bucket {
 func NewLimiter(prefix string) *Limiter {
 	return &Limiter{
 		Prefix:       prefix,
-		global:       new(int64),
-		buckets:      sync.Map{},
+		buckets:      map[string]*bucket{},
 		CustomLimits: []*CustomRateLimit{},
 	}
 }
@@ -69,7 +70,10 @@ func NewLimiter(prefix string) *Limiter {
 func (l *Limiter) getBucket(path string, store bool) *bucket {
 	path = ParseBucketKey(strings.TrimPrefix(path, l.Prefix))
 
-	bc, ok := l.buckets.Load(path)
+	l.bucketMu.Lock()
+	defer l.bucketMu.Unlock()
+
+	bc, ok := l.buckets[path]
 	if !ok && !store {
 		return nil
 	}
@@ -84,11 +88,11 @@ func (l *Limiter) getBucket(path string, store bool) *bucket {
 			}
 		}
 
-		l.buckets.Store(path, bc)
+		l.buckets[path] = bc
 		return bc
 	}
 
-	return bc.(*bucket)
+	return bc
 }
 
 func (l *Limiter) Acquire(ctx context.Context, path string) error {
@@ -107,7 +111,7 @@ func (l *Limiter) Acquire(ctx context.Context, path string) error {
 		until = b.reset
 	} else {
 		// maybe global rate limit has it
-		until = time.Unix(0, atomic.LoadInt64(l.global))
+		until = time.Unix(0, atomic.LoadInt64(&l.global))
 	}
 
 	if until.After(now) {
@@ -178,7 +182,7 @@ func (l *Limiter) Release(path string, headers http.Header) error {
 		at := time.Now().Add(time.Duration(i) * time.Second)
 
 		if global != "" { // probably true
-			atomic.StoreInt64(l.global, at.UnixNano())
+			atomic.StoreInt64(&l.global, at.UnixNano())
 		} else {
 			b.reset = at
 		}

internal/testenv/testenv.go

@@ -18,9 +18,9 @@ type Env struct {
 }
 
 var (
-	env  Env
-	err  error
-	once sync.Once
+	globalEnv Env
+	globalErr error
+	once      sync.Once
 )
 
 func Must(t *testing.T) Env {
@@ -33,41 +33,41 @@ func Must(t *testing.T) Env {
 
 func GetEnv() (Env, error) {
 	once.Do(getEnv)
-	return env, err
+	return globalEnv, globalErr
 }
 
 func getEnv() {
 	var token = os.Getenv("BOT_TOKEN")
 	if token == "" {
-		err = errors.New("missing $BOT_TOKEN")
+		globalErr = errors.New("missing $BOT_TOKEN")
 		return
 	}
 
 	var cid = os.Getenv("CHANNEL_ID")
 	if cid == "" {
-		err = errors.New("missing $CHANNEL_ID")
+		globalErr = errors.New("missing $CHANNEL_ID")
 		return
 	}
 
 	id, err := discord.ParseSnowflake(cid)
 	if err != nil {
-		err = errors.Wrap(err, "invalid $CHANNEL_ID")
+		globalErr = errors.Wrap(err, "invalid $CHANNEL_ID")
 		return
 	}
 
 	var sid = os.Getenv("VOICE_ID")
 	if sid == "" {
-		err = errors.New("missing $VOICE_ID")
+		globalErr = errors.New("missing $VOICE_ID")
 		return
 	}
 
 	vid, err := discord.ParseSnowflake(sid)
 	if err != nil {
-		err = errors.Wrap(err, "invalid $VOICE_ID")
+		globalErr = errors.Wrap(err, "invalid $VOICE_ID")
 		return
 	}
 
-	env = Env{
+	globalEnv = Env{
 		BotToken:  token,
 		ChannelID: discord.ChannelID(id),
 		VoiceChID: discord.ChannelID(vid),

utils/httputil/client.go

@@ -144,7 +144,10 @@ func (c *Client) RequestJSON(to interface{}, method, url string, opts ...Request
 }
 
 func (c *Client) Request(method, url string, opts ...RequestOption) (httpdriver.Response, error) {
+	// Error for the actual Do method.
 	var doErr error
+	// Error that represents the latest error in the chain.
+	var onRespErr error
 
 	var r httpdriver.Response
 	var status int
@@ -178,9 +181,6 @@ func (c *Client) Request(method, url string, opts ...RequestOption) (httpdriver.
 
 		r, doErr = c.Client.Do(q)
 
-		// Error that represents the latest error in the chain.
-		var onRespErr error
-
 		// Call OnResponse() even if the request failed.
 		for _, fn := range c.OnResponse {
 			// Be sure to call ALL OnResponse handlers.
@@ -189,12 +189,7 @@ func (c *Client) Request(method, url string, opts ...RequestOption) (httpdriver.
 			}
 		}
 
-		if onRespErr != nil {
-			return nil, errors.Wrap(err, "OnResponse handler failed")
-		}
-
-		// Retry if the request failed.
-		if doErr != nil {
+		if onRespErr != nil || doErr != nil {
 			continue
 		}
 
@@ -205,6 +200,10 @@ func (c *Client) Request(method, url string, opts ...RequestOption) (httpdriver.
 		break
 	}
 
+	if onRespErr != nil {
+		return nil, errors.Wrap(onRespErr, "OnResponse handler failed")
+	}
+
 	// If all retries failed:
 	if doErr != nil {
 		return nil, RequestError{doErr}

utils/httputil/errors.go

@@ -40,7 +40,7 @@ type HTTPError struct {
 func (err HTTPError) Error() string {
 	switch {
 	case err.Message != "":
-		return "Discord error: " + err.Message
+		return fmt.Sprintf("Discord %d error: %s", err.Status, err.Message)
 
 	case err.Code > 0:
 		return fmt.Sprintf("Discord returned status %d error code %d",