Add podio:input_collections parameter with regex support to filter collections from input files

.github/workflows/linux-eic-shell.yml

@@ -618,6 +618,63 @@ jobs:
         path: rec_${{ matrix.particle }}_1GeV_20GeV_${{ matrix.detector_config }}_${{ matrix.test_plugins }}.hists.root
         if-no-files-found: error
 
+  eicrecon-input-collections-test:
+    runs-on: ubuntu-24.04
+    needs:
+    - build
+    - npsim-gun
+    strategy:
+      matrix:
+        CXX: [g++]
+        particle: [e]
+        detector_config: [craterlake]
+    steps:
+    - name: Checkout .github
+      uses: actions/checkout@v5
+      with:
+        sparse-checkout: .github
+    - name: Download install directory
+      uses: actions/download-artifact@v5
+      with:
+        name: install-${{ matrix.CXX }}-eic-shell-Release-${{ env.platform }}-${{ env.release }}-ASAN
+    - name: Unarchive install directory
+      run: tar -xaf install.tar.zst
+    - uses: actions/download-artifact@v5
+      with:
+        name: sim_${{ matrix.particle }}_1GeV_20GeV_${{ matrix.detector_config }}.edm4hep.root
+    - uses: cvmfs-contrib/github-action-cvmfs@v5
+    - name: Run EICrecon with all collections (baseline)
+      uses: eic/run-cvmfs-osg-eic-shell@main
+      with:
+        platform-release: "${{ env.platform }}:${{ env.release }}"
+        setup: "/opt/detector/epic-${{ env.detector-version }}/bin/thisepic.sh"
+        run: |
+          export DETECTOR_CONFIG=${DETECTOR}_${{ matrix.detector_config }}
+          export LD_LIBRARY_PATH=$PWD/install/lib:$LD_LIBRARY_PATH
+          export JANA_PLUGIN_PATH=$PWD/install/lib/EICrecon/plugins${JANA_PLUGIN_PATH:+:${JANA_PLUGIN_PATH}}
+          $PWD/install/bin/eicrecon ${{env.JANA_OPTIONS}} ${{env.JANA_OPTIONS_GUN}} -Ppodio:output_file=rec_${{ matrix.particle }}_1GeV_20GeV_${{ matrix.detector_config }}_all_collections.edm4eic.root sim_${{ matrix.particle }}_1GeV_20GeV_${{ matrix.detector_config }}.edm4hep.root -Ppodio:output_collections=EventHeader,EcalBarrelScFiRawHits,EcalBarrelImagingRawHits,CentralTrackingRecHits -Pjana:nevents=5
+    - name: Run EICrecon without MCParticles (test input filtering)
+      uses: eic/run-cvmfs-osg-eic-shell@main
+      with:
+        platform-release: "${{ env.platform }}:${{ env.release }}"
+        setup: "/opt/detector/epic-${{ env.detector-version }}/bin/thisepic.sh"
+        run: |
+          export DETECTOR_CONFIG=${DETECTOR}_${{ matrix.detector_config }}
+          export LD_LIBRARY_PATH=$PWD/install/lib:$LD_LIBRARY_PATH
+          export JANA_PLUGIN_PATH=$PWD/install/lib/EICrecon/plugins${JANA_PLUGIN_PATH:+:${JANA_PLUGIN_PATH}}
+          # Test that our input_collections parameter works to exclude MCParticles - simulating real data without MC truth
+          $PWD/install/bin/eicrecon ${{env.JANA_OPTIONS}} ${{env.JANA_OPTIONS_GUN}} -Ppodio:input_collections=EventHeader,EcalBarrelScFiRawHits,EcalBarrelImagingRawHits,EcalBarrelScFiHits,EcalBarrelImagingHits,HcalBarrelRawHits,HcalBarrelHits,SiBarrelRawHits,SiBarrelHits -Ppodio:output_file=rec_${{ matrix.particle }}_1GeV_20GeV_${{ matrix.detector_config }}_no_mc.edm4eic.root sim_${{ matrix.particle }}_1GeV_20GeV_${{ matrix.detector_config }}.edm4hep.root -Ppodio:output_collections=EventHeader,EcalBarrelScFiRawHits,EcalBarrelImagingRawHits,CentralTrackingRecHits -Pjana:nevents=5
+    - uses: actions/upload-artifact@v4
+      with:
+        name: rec_${{ matrix.particle }}_1GeV_20GeV_${{ matrix.detector_config }}_all_collections.edm4eic.root
+        path: rec_${{ matrix.particle }}_1GeV_20GeV_${{ matrix.detector_config }}_all_collections.edm4eic.root
+        if-no-files-found: error
+    - uses: actions/upload-artifact@v4
+      with:
+        name: rec_${{ matrix.particle }}_1GeV_20GeV_${{ matrix.detector_config }}_no_mc.edm4eic.root
+        path: rec_${{ matrix.particle }}_1GeV_20GeV_${{ matrix.detector_config }}_no_mc.edm4eic.root
+        if-no-files-found: error
+
   eicrecon-benchmarks-plugins:
     runs-on: ubuntu-24.04
     needs:

src/services/io/podio/JEventSourcePODIO.cc

@@ -89,6 +89,26 @@ JEventSourcePODIO::JEventSourcePODIO(std::string resource_name, JApplication* ap
   GetApplication()->SetDefaultParameter("podio:print_type_table", print_type_table,
                                         "Print list of collection names and their types");
 
+  // Get the list of input collections to include
+  std::vector<std::string> input_collections;
+  GetApplication()->SetDefaultParameter(
+      "podio:input_collections", input_collections,
+      "Comma separated list of collection names to read from input. If not set, all collections "
+      "will be "
+      "read from input file. Setting this allows filtering which collections are loaded.");
+
+  m_input_collections = std::set<std::string>(input_collections.begin(), input_collections.end());
+
+  // Log input collections configuration for debugging
+  if (!input_collections.empty()) {
+    m_log->info("podio:input_collections parameter set - will only load specified collections:");
+    for (const auto& coll : input_collections) {
+      m_log->info("  - {}", coll);
+    }
+  } else {
+    m_log->debug("podio:input_collections not set - will load all available collections");
+  }
+
   // Hopefully we won't need to reimplement background event merging. Using podio frames, it looks like we would
   // have to do a deep copy of all data in order to insert it into the same frame, which would probably be
   // quite inefficient.
@@ -217,9 +237,27 @@ void JEventSourcePODIO::GetEvent(std::shared_ptr<JEvent> _event) {
     }
   }
 
-  // Insert contents odf frame into JFactories
+  // Insert contents of frame into JFactories
   VisitPodioCollection<InsertingVisitor> visit;
+
+  // Log collection filtering info on first event only
+  static bool first_event = true;
+  if (first_event && !m_input_collections.empty()) {
+    m_log->info("Filtering input collections - loading {} of {} available collections",
+                m_input_collections.size(), frame->getAvailableCollections().size());
+    first_event = false;
+  }
+
   for (const std::string& coll_name : frame->getAvailableCollections()) {
+    // Filter collections based on input_collections parameter
+    // If input_collections is not set (empty), load all collections (default behavior)
+    // If input_collections is set, only load collections that are in the set
+    if (!m_input_collections.empty() &&
+        m_input_collections.find(coll_name) == m_input_collections.end()) {
+      // Skip this collection as it's not in the input_collections list
+      continue;
+    }
+
     const podio::CollectionBase* collection = frame->get(coll_name);
     InsertingVisitor visitor(event, coll_name);
     visit(visitor, *collection);

src/services/io/podio/JEventSourcePODIO.h

@@ -11,6 +11,7 @@
 #include <spdlog/logger.h>
 #include <cstddef>
 #include <memory>
+#include <set>
 #include <string>
 
 #if ((JANA_VERSION_MAJOR == 2) && (JANA_VERSION_MINOR >= 3)) || (JANA_VERSION_MAJOR > 2)
@@ -49,6 +50,8 @@ class JEventSourcePODIO : public JEventSource {
   bool m_run_forever       = false;
   bool m_use_event_headers = true;
 
+  std::set<std::string> m_input_collections; // config. parameter
+
 private:
   std::shared_ptr<spdlog::logger> m_log;
 };