Fix null err access

Author: milot-mirdita

backend/server.go

@@ -729,11 +729,16 @@ func server(jobsystem JobSystem, config ConfigRoot) {
 		}
 
 		status, err := jobsystem.Status(ticket.Id)
-		if err != nil || status != StatusComplete {
+		if err != nil {
 			http.Error(w, err.Error(), http.StatusBadRequest)
 			return
 		}
 
+		if status != StatusComplete {
+			http.Error(w, "Job is not complete", http.StatusBadRequest)
+			return
+		}
+
 		name := "mmseqs_results_" + string(ticket.Id) + ".tar.gz"
 		path := filepath.Join(filepath.Clean(config.Paths.Results), string(ticket.Id), name)
 		if _, err := os.Stat(path); os.IsNotExist(err) {
@@ -762,11 +767,16 @@ func server(jobsystem JobSystem, config ConfigRoot) {
 		}
 
 		status, err := jobsystem.Status(ticket.Id)
-		if err != nil || status != StatusComplete {
+		if err != nil {
 			http.Error(w, err.Error(), http.StatusBadRequest)
 			return
 		}
 
+		if status != StatusComplete {
+			http.Error(w, "Job is not complete", http.StatusBadRequest)
+			return
+		}
+
 		name := "folddisco_results_" + string(ticket.Id) + ".tar.gz"
 		path := filepath.Join(filepath.Clean(config.Paths.Results), string(ticket.Id), name)
 		if _, err := os.Stat(path); os.IsNotExist(err) {