From a192bb549e78127361ad8a0a8f2500a04acc2a99 Mon Sep 17 00:00:00 2001
From: Thomas Madlener <thomas.madlener@desy.de>
Date: Wed, 19 Feb 2025 15:07:27 +0100
Subject: [PATCH] Keep backwards compatibility with older podio versions

---
 k4FWCore/components/IOSvc.cpp                 |  7 ++++++-
 k4FWCore/src/PodioDataSvc.cpp                 | 17 +++++++++++++++++
 test/k4FWCoreTest/scripts/CheckOutputFiles.py |  5 +++--
 3 files changed, 26 insertions(+), 3 deletions(-)

diff --git a/k4FWCore/components/IOSvc.cpp b/k4FWCore/components/IOSvc.cpp
index 2a2b770b..634e9eba 100644
--- a/k4FWCore/components/IOSvc.cpp
+++ b/k4FWCore/components/IOSvc.cpp
@@ -22,6 +22,7 @@
 #include "podio/Frame.h"
 #include "podio/FrameCategories.h"
 #include "podio/Reader.h"
+#include "podio/podioVersion.h"
 
 #include "k4FWCore/FunctionalUtils.h"
 #include "k4FWCore/KeepDropSwitch.h"
@@ -116,7 +117,11 @@ std::tuple<std::vector<podio::CollectionBase*>, std::vector<std::string>, podio:
     if (m_nextEntry < m_entries) {
       debug() << "Reading event " << m_nextEntry << endmsg;
       debug() << "Reading collections " << m_collectionNames << endmsg;
-      frame = podio::Frame(m_reader->readEvent(m_nextEntry, m_collectionNames));
+#if PODIO_BUILD_VERSION <= PODIO_VERSION(1, 2, 0)
+      frame = m_reader->readEvent(m_nextEntry);
+#else
+      frame = m_reader->readEvent(m_nextEntry, m_collectionNames);
+#endif
     } else {
       return std::make_tuple(std::vector<podio::CollectionBase*>(), std::vector<std::string>(), std::move(frame));
     }
diff --git a/k4FWCore/src/PodioDataSvc.cpp b/k4FWCore/src/PodioDataSvc.cpp
index 02bda07b..8b2ba40e 100644
--- a/k4FWCore/src/PodioDataSvc.cpp
+++ b/k4FWCore/src/PodioDataSvc.cpp
@@ -24,6 +24,7 @@
 #include "k4FWCore/DataWrapper.h"
 
 #include "podio/CollectionBase.h"
+#include "podio/podioVersion.h"
 
 /// Service initialisation
 StatusCode PodioDataSvc::initialize() {
@@ -104,7 +105,15 @@ StatusCode PodioDataSvc::i_setRoot(std::string root_path, IOpaqueAddress* pRootA
   // create a new frame
   if (m_reading_from_file) {
     debug() << "Reading event " << m_eventNum + m_1stEvtEntry << ", using collections: " << m_collsToRead << endmsg;
+#if PODIO_BUILD_VERSION <= PODIO_VERSION(1, 2, 0)
+    if (!m_collsToRead.empty()) {
+      warning() << "Trying to limit collections that are read, but podio does only support this with version > 1.2"
+                << endmsg;
+    }
+    m_eventframe = podio::Frame(m_reader.readEntry("events", m_eventNum + m_1stEvtEntry));
+#else
     m_eventframe = podio::Frame(m_reader.readEntry("events", m_eventNum + m_1stEvtEntry, m_collsToRead));
+#endif
   } else {
     m_eventframe = podio::Frame();
   }
@@ -115,7 +124,15 @@ StatusCode PodioDataSvc::i_setRoot(std::string root_path, DataObject* pRootObj)
   // create a new frame
   if (m_reading_from_file) {
     debug() << "Reading event " << m_eventNum + m_1stEvtEntry << ", using collections: " << m_collsToRead << endmsg;
+#if PODIO_BUILD_VERSION <= PODIO_VERSION(1, 2, 0)
+    if (!m_collsToRead.empty()) {
+      warning() << "Trying to limit collections that are read, but podio does only support this with version > 1.2"
+                << endmsg;
+    }
+    m_eventframe = podio::Frame(m_reader.readEntry("events", m_eventNum + m_1stEvtEntry));
+#else
     m_eventframe = podio::Frame(m_reader.readEntry("events", m_eventNum + m_1stEvtEntry, m_collsToRead));
+#endif
   } else {
     m_eventframe = podio::Frame();
   }
diff --git a/test/k4FWCoreTest/scripts/CheckOutputFiles.py b/test/k4FWCoreTest/scripts/CheckOutputFiles.py
index a58e5b31..4639c650 100644
--- a/test/k4FWCoreTest/scripts/CheckOutputFiles.py
+++ b/test/k4FWCoreTest/scripts/CheckOutputFiles.py
@@ -120,8 +120,9 @@ def check_metadata(filename, expected_metadata):
     ],
 )
 
-check_collections("output_k4test_exampledata_limited.root", ["MCParticles", "Links"])
-check_collections("functional_limited_input.root", ["MCParticles", "Links"])
+if podio.version.build_version > podio.version.parse("1.2.0"):
+    check_collections("output_k4test_exampledata_limited.root", ["MCParticles", "Links"])
+    check_collections("functional_limited_input.root", ["MCParticles", "Links"])
 
 mix_collections = [
     # From file