Modules/src/EmptySourceFromEventIDs.cc

0001 #include "FWCore/Framework/interface/Event.h"
0002 #include "FWCore/Framework/interface/InputSource.h"
0003 #include "FWCore/ParameterSet/interface/ConfigurationDescriptions.h"
0004 #include "FWCore/ParameterSet/interface/ParameterSetDescription.h"
0005 #include "FWCore/Sources/interface/IDGeneratorSourceBase.h"
0006
0007 /*
0008  * IDGeneratorSourceBase implements the logic to generate run, lumi, and event numbers, and event timestamps.
0009  * These will actually be overwritten by this source, but it's easier to do that than to write a new source base
0010  * type from scratch.
0011  */
0012
0013 class EmptySourceFromEventIDs : public edm::IDGeneratorSourceBase<edm::InputSource> {
0014 public:
0015   explicit EmptySourceFromEventIDs(edm::ParameterSet const&, edm::InputSourceDescription const&);
0016   ~EmptySourceFromEventIDs() override = default;
0017
0018   static void fillDescriptions(edm::ConfigurationDescriptions& descriptions);
0019
0020 private:
0021   bool setRunAndEventInfo(edm::EventID& id, edm::TimeValue_t& time, edm::EventAuxiliary::ExperimentType& type) override;
0022   void readEvent_(edm::EventPrincipal& e) override;
0023
0024   std::vector<edm::EventID> events_;
0025 };
0026
0027 // Note that almost all configuration parameters passed to IDGeneratorSourceBase will effectively be ignored, because
0028 // the EmptySourceFromEventIDs will explicitly set the run, lumi, and event numbers, the timestamp, and the event type.
0029 EmptySourceFromEventIDs::EmptySourceFromEventIDs(edm::ParameterSet const& config,
0030                                                  edm::InputSourceDescription const& desc)
0031     : IDGeneratorSourceBase<InputSource>(config, desc, false),
0032       events_{config.getUntrackedParameter<std::vector<edm::EventID>>("events")}  // List of event ids to create
0033 {
0034   // Invert the order of the events so they can efficiently be popped off the back of the vector
0035   std::reverse(events_.begin(), events_.end());
0036 }
0037
0038 bool EmptySourceFromEventIDs::setRunAndEventInfo(edm::EventID& event,
0039                                                  edm::TimeValue_t& time,
0040                                                  edm::EventAuxiliary::ExperimentType& type) {
0041   if (events_.empty()) {
0042     return false;
0043   }
0044
0045   event = events_.back();
0046   events_.pop_back();
0047   return true;
0048 }
0049
0050 void EmptySourceFromEventIDs::readEvent_(edm::EventPrincipal& e) {
0051   doReadEvent(e, [](auto const&) {});
0052 }
0053
0054 void EmptySourceFromEventIDs::fillDescriptions(edm::ConfigurationDescriptions& descriptions) {
0055   edm::ParameterSetDescription desc;
0056   desc.setComment("Creates runs, lumis and events (containing no products) based on the provided list of event ids.");
0057   edm::IDGeneratorSourceBase<edm::InputSource>::fillDescription(desc);
0058
0059   desc.addUntracked<std::vector<edm::EventID>>("events", {});
0060   descriptions.add("source", desc);
0061 }
0062
0063 #include "FWCore/Framework/interface/InputSourceMacros.h"
0064 DEFINE_FWK_INPUT_SOURCE(EmptySourceFromEventIDs);