EDConsumerBase.h

#ifndef FWCore_Framework_EDConsumerBase_h
#define FWCore_Framework_EDConsumerBase_h
// -*- C++ -*-
//
// Package:     FWCore/Framework
// Class  :     EDConsumerBase
// 
/**\class edm::EDConsumerBase

 Description: Allows declaration of what data is being consumed

 Usage:
    The EDM modules all inherit from this base class

*/
//
// Original Author:  Chris Jones
//         Created:  Tue, 02 Apr 2013 21:35:53 GMT
//

// system include files
#include <map>
#include <string>
#include <vector>

// user include files
#include "FWCore/Framework/interface/ProductHolderIndexAndSkipBit.h"
#include "FWCore/ServiceRegistry/interface/ConsumesInfo.h"
#include "FWCore/Utilities/interface/TypeID.h"
#include "FWCore/Utilities/interface/TypeToGet.h"
#include "FWCore/Utilities/interface/InputTag.h"
#include "FWCore/Utilities/interface/EDGetToken.h"
#include "FWCore/Utilities/interface/SoATuple.h"
#include "DataFormats/Provenance/interface/BranchType.h"
#include "FWCore/Utilities/interface/ProductHolderIndex.h"
#include "FWCore/Utilities/interface/ProductKindOfType.h"
#include "FWCore/Utilities/interface/ProductLabels.h"


// forward declarations

namespace edm {
  class ModuleDescription;
  class ProductHolderIndexHelper;
  class ProductRegistry;
  class ConsumesCollector;
  template<typename T> class WillGetIfMatch;

  class EDConsumerBase
  {
    
  public:
    EDConsumerBase() : frozen_(false) {}
    virtual ~EDConsumerBase();
    
    // ---------- const member functions ---------------------
    ProductHolderIndexAndSkipBit indexFrom(EDGetToken, BranchType, TypeID const&) const;

    void itemsToGet(BranchType, std::vector<ProductHolderIndexAndSkipBit>&) const;
    void itemsMayGet(BranchType, std::vector<ProductHolderIndexAndSkipBit>&) const;

    std::vector<ProductHolderIndexAndSkipBit> const& itemsToGetFromEvent() const { return itemsToGetFromEvent_; }

    ///\return true if the product corresponding to the index was registered via consumes or mayConsume call
    bool registeredToConsume(ProductHolderIndex, bool, BranchType) const;
    
    ///\return true of TypeID corresponds to a type specified in a consumesMany call
    bool registeredToConsumeMany(TypeID const&, BranchType) const;
    // ---------- static member functions --------------------
    
    // ---------- member functions ---------------------------
    void updateLookup(BranchType iBranchType,
                      ProductHolderIndexHelper const&);
    
    typedef ProductLabels Labels;
    void labelsForToken(EDGetToken iToken, Labels& oLabels) const;
    
    void modulesDependentUpon(const std::string& iProcessName,
                              std::vector<const char*>& oModuleLabels) const;

    void modulesWhoseProductsAreConsumed(std::vector<ModuleDescription const*>& modules,
                                         ProductRegistry const& preg,
                                         std::map<std::string, ModuleDescription const*> const& labelsToDesc,
                                         std::string const& processName) const;

    std::vector<ConsumesInfo> consumesInfo() const;

  protected:
    friend class ConsumesCollector;
    template<typename T> friend class WillGetIfMatch;
    ///Use a ConsumesCollector to gather consumes information from helper functions
    ConsumesCollector consumesCollector();
    
    template <typename ProductType, BranchType B=InEvent>
    EDGetTokenT<ProductType> consumes(edm::InputTag const& tag) {
      TypeToGet tid=TypeToGet::make<ProductType>();
      return EDGetTokenT<ProductType>{recordConsumes(B,tid, checkIfEmpty(tag),true)};
    }

    EDGetToken consumes(const TypeToGet& id, edm::InputTag const& tag) {
      return EDGetToken{recordConsumes(InEvent, id, checkIfEmpty(tag), true)};
    }

    template <BranchType B>
    EDGetToken consumes(TypeToGet const& id, edm::InputTag const& tag) {
      return EDGetToken{recordConsumes(B, id, checkIfEmpty(tag), true)};
    }

    template <typename ProductType, BranchType B=InEvent>
    EDGetTokenT<ProductType> mayConsume(edm::InputTag const& tag) {
      TypeToGet tid=TypeToGet::make<ProductType>();
      return EDGetTokenT<ProductType>{recordConsumes(B, tid, checkIfEmpty(tag), false)};
    }

    EDGetToken mayConsume(const TypeToGet& id, edm::InputTag const& tag) {
      return mayConsume<InEvent>(id,tag);
    }

    template <BranchType B>
    EDGetToken mayConsume(const TypeToGet& id, edm::InputTag const& tag) {
      return EDGetToken{recordConsumes(B,id,checkIfEmpty(tag),false)};
    }

    template <typename ProductType, BranchType B=InEvent>
    void consumesMany() {
      TypeToGet tid=TypeToGet::make<ProductType>();
      consumesMany<B>(tid);
    }

    void consumesMany(const TypeToGet& id) {
      consumesMany<InEvent>(id);
    }

    template <BranchType B>
    void consumesMany(const TypeToGet& id) {
      recordConsumes(B,id,edm::InputTag{},true);
    }

  private:
    EDConsumerBase(const EDConsumerBase&) = delete;
    
    const EDConsumerBase& operator=(const EDConsumerBase&) = delete;
    
    unsigned int recordConsumes(BranchType iBranch, TypeToGet const& iType, edm::InputTag const& iTag, bool iAlwaysGets);

    void throwTypeMismatch(edm::TypeID const&, EDGetToken) const;
    void throwBranchMismatch(BranchType, EDGetToken) const;
    void throwBadToken(edm::TypeID const& iType, EDGetToken iToken) const;
    void throwConsumesCallAfterFrozen(TypeToGet const&, InputTag const&) const;

    edm::InputTag const& checkIfEmpty(edm::InputTag const& tag);
    // ---------- member data --------------------------------

    struct TokenLookupInfo {
      TokenLookupInfo(edm::TypeID const& iID,
                      ProductHolderIndex iIndex,
                      bool skipCurrentProcess,
                      BranchType iBranch):
        m_type(iID),m_index(iIndex, skipCurrentProcess), m_branchType(iBranch){}
      edm::TypeID m_type;
      ProductHolderIndexAndSkipBit m_index;
      BranchType m_branchType;
    };

    struct LabelPlacement {
      LabelPlacement(unsigned int iStartOfModuleLabel,
                     unsigned short iDeltaToProductInstance,
                     unsigned short iDeltaToProcessName):
      m_startOfModuleLabel(iStartOfModuleLabel),
      m_deltaToProductInstance(iDeltaToProductInstance),
      m_deltaToProcessName(iDeltaToProcessName) {}
      unsigned int m_startOfModuleLabel;
      unsigned short m_deltaToProductInstance;
      unsigned short m_deltaToProcessName;
    };

    //define the purpose of each 'column' in m_tokenInfo
    enum {kLookupInfo,kAlwaysGets,kLabels,kKind};
    edm::SoATuple<TokenLookupInfo,bool,LabelPlacement,edm::KindOfType> m_tokenInfo;

    //m_tokenStartOfLabels holds the entries into this container
    // for each of the 3 labels needed to id the data
    std::vector<char> m_tokenLabels;

    std::vector<ProductHolderIndexAndSkipBit> itemsToGetFromEvent_;

    bool frozen_;
  };
}

#endif