From f8c7325ac0ca100c86f65253ce6e19a5a517d271 Mon Sep 17 00:00:00 2001
From: tmadlener <thomas.madlener@desy.de>
Date: Fri, 17 Nov 2023 21:00:53 +0100
Subject: [PATCH] Enable CLI override for reading all collections

---
 k4FWCore/components/PodioInput.cpp            | 11 +++++++++++
 k4FWCore/components/PodioInput.h              |  2 ++
 test/k4FWCoreTest/CMakeLists.txt              |  1 +
 .../options/checkExampleEventData.py          | 19 ++++++++++++-------
 4 files changed, 26 insertions(+), 7 deletions(-)

diff --git a/k4FWCore/components/PodioInput.cpp b/k4FWCore/components/PodioInput.cpp
index acb4d47c..cbb98921 100644
--- a/k4FWCore/components/PodioInput.cpp
+++ b/k4FWCore/components/PodioInput.cpp
@@ -186,6 +186,17 @@ PodioInput::PodioInput(const std::string& name, ISvcLocator* svcLoc) : Consumer(
   fillReaders();
 }
 
+StatusCode PodioInput::initialize() {
+  // If someone uses the collections property from the command line and passes
+  // an empty string we assume they want all collections (as a simple way to
+  // override whatever is in the options file)
+  if (m_collectionNames.size() == 1 && m_collectionNames[0].empty()) {
+    m_collectionNames.clear();
+  }
+
+  return StatusCode::SUCCESS;
+}
+
 void PodioInput::operator()() const {
   if (m_podioDataSvc->getEventFrame().get(edm4hep::EventHeaderName)) {
     m_readers[edm4hep::EventHeaderCollection::typeName](edm4hep::EventHeaderName);
diff --git a/k4FWCore/components/PodioInput.h b/k4FWCore/components/PodioInput.h
index 978d821e..a8c4a59f 100644
--- a/k4FWCore/components/PodioInput.h
+++ b/k4FWCore/components/PodioInput.h
@@ -42,6 +42,8 @@ class PodioInput final : public Gaudi::Functional::Consumer<void(), BaseClass_t>
   PodioInput(const std::string& name, ISvcLocator* svcLoc);
   void operator()() const override;
 
+  StatusCode initialize() final;
+
 private:
   template <typename T> void maybeRead(std::string_view collName) const;
   void                       fillReaders();
diff --git a/test/k4FWCoreTest/CMakeLists.txt b/test/k4FWCoreTest/CMakeLists.txt
index 19f40204..85e261e5 100644
--- a/test/k4FWCoreTest/CMakeLists.txt
+++ b/test/k4FWCoreTest/CMakeLists.txt
@@ -60,6 +60,7 @@ endfunction()
 add_test_with_env(CreateExampleEventData options/createExampleEventData.py)
 
 add_test_with_env(CheckExampleEventData options/checkExampleEventData.py PROPERTIES DEPENDS CreateExampleEventData)
+add_test_with_env(CheckExampleEventData_noCollections options/checkExampleEventData.py --collections= PROPERTIES DEPENDS CreateExampleEventData)
 add_test_with_env(CheckExampleEventData_toolong -n 999 options/checkExampleEventData.py PROPERTIES PASS_REGULAR_EXPRESSION
                   "Application Manager Terminated successfully with a user requested ScheduledStop" DEPENDS CreateExampleEventData)
 add_test_with_env(CheckExampleEventData_unbounded options/checkExampleEventData.py -n 999 PROPERTIES PASS_REGULAR_EXPRESSION
diff --git a/test/k4FWCoreTest/options/checkExampleEventData.py b/test/k4FWCoreTest/options/checkExampleEventData.py
index 80be3b52..2f635132 100644
--- a/test/k4FWCoreTest/options/checkExampleEventData.py
+++ b/test/k4FWCoreTest/options/checkExampleEventData.py
@@ -26,14 +26,19 @@
 
 from Configurables import PodioInput
 
+from k4FWCore.parseArgs import parser
+
+parser.add_argument(
+    "--collections",
+    action="extend",
+    nargs="?",
+    help="The input collections to read",
+    default=["VectorFloat", "MCParticles", "SimTrackerHits", "TrackerHits", "Tracks"],
+)
+my_args = parser.parse_known_args()[0]
+
 inp = PodioInput()
-inp.collections = [
-    "VectorFloat",
-    "MCParticles",
-    "SimTrackerHits",
-    "TrackerHits",
-    "Tracks",
-]
+inp.collections = my_args.collections
 
 from Configurables import k4FWCoreTest_CheckExampleEventData