From 695924b8d8f14564b6155a550c84ba8b6fdb4497 Mon Sep 17 00:00:00 2001
From: Leonhard Reichenbach <leonhard.reichenbach@cern.ch>
Date: Wed, 18 Oct 2023 18:03:48 +0200
Subject: [PATCH] add error message for missing input files

---
 CLDConfig/CLDReconstruction.py | 9 ++++++++-
 1 file changed, 8 insertions(+), 1 deletion(-)

diff --git a/CLDConfig/CLDReconstruction.py b/CLDConfig/CLDReconstruction.py
index 7d08a83..aae9bd8 100644
--- a/CLDConfig/CLDReconstruction.py
+++ b/CLDConfig/CLDReconstruction.py
@@ -17,6 +17,7 @@
 # limitations under the License.
 #
 import os
+import sys
 from Gaudi.Configuration import *
 
 from Configurables import k4DataSvc, MarlinProcessorWrapper
@@ -65,12 +66,18 @@
 
 output_basename = my_opts.outputBasename
 
-input_files = [""]
+# Set input files here or via --inputFiles
+input_files = []
+
 if my_opts.inputFiles is not None:
     input_files = my_opts.inputFiles
 print(f"opts: {my_opts}")
 print(f"input_files: {input_files}")
 
+if not input_files:
+    print("Error: missing input files, set them via --inputFiles")
+    sys.exit(1)
+
 if input_files[0].endswith(".slcio"):
     CONFIG["InputMode"] = "LCIO"
 elif input_files[0].endswith(".root"):