Utilise http.MaxBytesReader

webhook_verifier.go

@@ -17,9 +17,6 @@ var (
 
 	// ErrInvalidSignatureFormat is returned when the signature format is invalid.
 	ErrInvalidSignatureFormat = errors.New("invalid signature format")
-
-	// ErrRequestExceedsExpectation is returned when the request exceeds the limit
-	ErrRequestExceedsExpectation = errors.New("request body size exceeds limit")
 )
 
 // signatureRegexp matches the Paddle-Signature header format, e.g.:
@@ -55,17 +52,14 @@ func (wv *WebhookVerifier) Verify(req *http.Request) (bool, error) {
 	h1 := matches[0][2]
 
 	const maxBodySize = 2 << 20 // 2 MB
-	limitedReader := io.LimitReader(req.Body, maxBodySize)
 
-	body, err := io.ReadAll(limitedReader)
+	req.Body = http.MaxBytesReader(nil, req.Body, maxBodySize)
+
+	body, err := io.ReadAll(req.Body)
 	if err != nil {
 		return false, err
 	}
 
-	if len(body) == maxBodySize {
-		return false, ErrRequestExceedsExpectation
-	}
-
 	req.Body = io.NopCloser(bytes.NewBuffer(body))
 
 	mac := hmac.New(sha256.New, wv.secretKey)