return json even if no packages are queued; fix 404

main.go

@@ -86,6 +86,14 @@ func main() {
 		if *exitCodeFlag {
 			os.Exit(20)
 		}
+	} else {
+		log.Debugf("no packages in queue")
+		if *jsonFlag {
+			err = json.NewEncoder(os.Stdout).Encode(JSONOut{
+				Total:    len(packagesInQueue),
+				Packages: packagesInQueue,
+			})
+		}
 	}
 }
 
@@ -127,10 +135,10 @@ func ALHPBuildQueuePkgbase() ([]string, error) {
 	}
 	defer resp.Body.Close()
 
-	if resp.StatusCode != http.StatusOK {
-		return nil, fmt.Errorf("ALHP api returned HTTP %d", resp.StatusCode)
-	} else if resp.StatusCode == http.StatusNotFound {
+	if resp.StatusCode == http.StatusNotFound {
 		return nil, nil
+	} else if resp.StatusCode != http.StatusOK {
+		return nil, fmt.Errorf("ALHP api returned HTTP %d", resp.StatusCode)
 	}
 
 	bResp, err := io.ReadAll(resp.Body)