Allow 0 as `IMGPROXY_FALLBACK_IMAGE_HTTP_CODE` value

CHANGELOG.md

@@ -7,6 +7,7 @@
 
 # Fix
 - Fix handling `#` symbols in `local://`, `s3://`, `gcs://`, `abs://`, and `swift://` URLs.
+- Fix `IMGPROXY_FALLBACK_IMAGE_HTTP_CODE` value check. Allow `0` value.
 
 ## [3.25.0] - 2024-07-08
 ### Add

config/config.go

@@ -752,7 +752,7 @@ func Configure() error {
 		return fmt.Errorf("Fallback image TTL should be greater than or equal to 0, now - %d\n", TTL)
 	}
 
-	if FallbackImageHTTPCode < 100 || FallbackImageHTTPCode > 599 {
+	if FallbackImageHTTPCode != 0 && (FallbackImageHTTPCode < 100 || FallbackImageHTTPCode > 599) {
 		return errors.New("Fallback image HTTP code should be between 100 and 599")
 	}