Add inputReader for easy reading of edm4hep or lcio files

k4MarlinWrapper/python/k4MarlinWrapper/inputReader.py

@@ -0,0 +1,56 @@
+#
+# Copyright (c) 2019-2024 Key4hep-Project.
+#
+# This file is part of Key4hep.
+# See https://key4hep.github.io/key4hep-doc/ for further info.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+#
+
+import sys
+from Configurables import LcioEvent, PodioInput, MarlinProcessorWrapper, EDM4hep2LcioTool
+
+def create_reader(input_files, evtSvc):
+    """Create the appropriate reader for the input files"""
+    if input_files[0].endswith(".slcio"):
+        if any(not f.endswith(".slcio") for f in input_files):
+            print("All input files need to have the same format (LCIO)")
+            sys.exit(1)
+
+        read = LcioEvent()
+        read.Files = input_files
+    else:
+        if any(not f.endswith(".root") for f in input_files):
+            print("All input files need to have the same format (EDM4hep)")
+            sys.exit(1)
+        read = PodioInput("PodioInput")
+        evtSvc.inputs = input_files
+
+    return read
+
+def attach_edm4hep2lcio_conversion(algList, read):
+    """Attach the edm4hep to lcio conversion if necessary e.g. when using create_reader. Should only be run after algList is complete."""
+    if not isinstance(read, PodioInput):
+        # nothing to convert :)
+        return
+
+     # find first wrapper
+    for alg in algList:
+        if isinstance(alg, MarlinProcessorWrapper):
+            break
+
+    EDM4hep2LcioInput = EDM4hep2LcioTool("InputConversion")
+    EDM4hep2LcioInput.convertAll = True
+    # Adjust for the different naming conventions
+    EDM4hep2LcioInput.collNameMapping = {"MCParticles": "MCParticle"}
+    alg.EDM4hep2LcioTool = EDM4hep2LcioInput