MCDBSource.cc

Go to the documentation of this file.

#include <iostream>
#include <utility>
#include <string>

#include <boost/regex.hpp>

#include "mcdb.hpp"

#include "FWCore/Framework/interface/InputSourceMacros.h"
#include "FWCore/Framework/interface/MakerMacros.h"
#include "FWCore/Framework/interface/Event.h"
#include "FWCore/Framework/interface/Run.h"
#include "FWCore/ParameterSet/interface/ParameterSet.h"
#include "FWCore/MessageLogger/interface/MessageLogger.h"

#include "SimDataFormats/GeneratorProducts/interface/LesHouches.h"
#include "GeneratorInterface/LHEInterface/interface/LHEEvent.h"
#include "GeneratorInterface/LHEInterface/interface/LHEReader.h"

#include "LHESource.h"

using namespace lhef;

class MCDBSource : public LHESource {
    public:
    explicit MCDBSource(const edm::ParameterSet &params,
                        const edm::InputSourceDescription &desc);
    virtual ~MCDBSource();
};

static std::pair<std::vector<std::string>, unsigned int>
            getFileURLs(const edm::ParameterSet &params)
{
    unsigned int articleId = params.getParameter<unsigned int>("articleID");

    edm::LogInfo("Generator|LHEInterface")
        << "Reading article id " << articleId << " from MCDB."
        << std::endl;

    mcdb::MCDB mcdb;

    mcdb::Article article = mcdb.getArticle(articleId);

    edm::LogInfo("Generator|LHEInterface")
        << "Title: " << article.title() << std::endl
        << "First author: " << article.authors()[0].firstName() << " "
        << article.authors()[0].lastName() << std::endl
        << "Number of authors: " << article.authors().size() << std::endl
        << "Abstract: " << article.abstract() << std::endl
        << "Generator: " << article.generator().name()
        << ", " << article.generator().version() << std::endl
        << "Number of files: " << article.files().size() << std::endl
        << "Files: " << std::endl;

    std::vector<std::string> supportedProtocols = 
        params.getUntrackedParameter< std::vector<std::string> >(
                            "supportedProtocols");

    boost::regex filter(params.getUntrackedParameter<std::string>(
                            "filter", "\\.lhef?$"),
                        boost::regex_constants::normal |
                        boost::regex_constants::icase);

    unsigned int firstEvent =
        params.getUntrackedParameter<unsigned int>("skipEvents", 0);

    unsigned int fcount = 0;
    std::vector<std::string> fileURLs;
    for(std::vector<mcdb::File>::iterator file = article.files().begin();
        file != article.files().end(); ++file) {
        std::string fileURL;
        for(std::vector<std::string>::const_iterator prot =
                        supportedProtocols.begin();
            prot != supportedProtocols.end(); ++prot) {
            for(std::vector<std::string>::const_iterator path =
                            file->paths().begin();
                path != file->paths().end(); ++path) {
                if (path->substr(0, prot->length() + 1) ==
                    *prot + ":") {
                    fileURL = *path;
                    break;
                }
            }
            if (!fileURL.empty())
                break;
        }

        if (fileURL.empty())
            throw cms::Exception("Generator|LHEInterface")
                << "MCDB did not contain any URLs with"
                   " supported protocols for at least one"
                   " file." << std::endl;

        if (!boost::regex_search(fileURL, filter))
            continue;

        int nEvents = file->eventsNumber();
        if (nEvents > 0 && (int)firstEvent >= nEvents) {
            firstEvent -= nEvents;
            continue;
        }

        fileURLs.push_back(fileURL);
        fcount++;
        edm::LogInfo("Generator|LHEInterface") << "Adding file n. " << fcount << " " << fileURL;
    }

    return std::make_pair(fileURLs, firstEvent);
}

static edm::ParameterSet augmentPSetFromMCDB(const edm::ParameterSet &params)
{
    // note that this is inherently ugly, but the only way to
    // pass the file URLs to ExternalInputSource, as the MCDB client
    // is nothing but an MCDB to URL converter
    // all modified parameters are untracked, so the provenance is
    // unchanged

    std::pair<std::vector<std::string>, unsigned int> result =
                            getFileURLs(params);

    edm::ParameterSet newParams = params;
    newParams.addUntrackedParameter<std::vector<std::string> >(
                        "fileNames", result.first);
    newParams.addUntrackedParameter<unsigned int>(
                        "skipEvents", result.second);

    return newParams;
}

MCDBSource::MCDBSource(const edm::ParameterSet &params,
                       const edm::InputSourceDescription &desc) :
        LHESource(augmentPSetFromMCDB(params), desc)
{
}

MCDBSource::~MCDBSource()
{
}

DEFINE_FWK_INPUT_SOURCE(MCDBSource);