NgapRequestHandler.cc

// NgapContainer.cc
 
// -*- mode: c++; c-basic-offset:4 -*-
 
// This file is part of ngap_module, A C++ module that can be loaded in to
// the OPeNDAP Back-End Server (BES) and is able to handle remote requests.
 
// Copyright (c) 2020 OPeNDAP, Inc.
// Author: Nathan Potter <ndp@opendap.org>
//
// This library is free software; you can redistribute it and/or
// modify it under the terms of the GNU Lesser General Public
// License as published by the Free Software Foundation; either
// version 2.1 of the License, or (at your option) any later version.
//
// This library is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
// Lesser General Public License for more details.
//
// You should have received a copy of the GNU Lesser General Public
// License along with this library; if not, write to the Free Software
// Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
//
// You can contact OPeNDAP, Inc. at PO Box 112, Saunderstown, RI. 02874-0112.
// Authors:
//      ndp       Nathan Potter <ndp@opendap.org>
 
#include "config.h"
 
#include <libdap/InternalErr.h>
 
#include <BESResponseHandler.h>
#include <BESResponseNames.h>
#include <BESVersionInfo.h>
#include <BESConstraintFuncs.h>
#include <BESServiceRegistry.h>
#include <TheBESKeys.h>
#include <BESLog.h>
#include <BESUtil.h>
 
#include "NgapRequestHandler.h"
#include "NgapNames.h"
 
using namespace std;
using namespace libdap;
using namespace ngap;
 
// CMR caching
unsigned int NgapRequestHandler::d_cmr_cache_size_items = 100;    // Entries, not size in bytes, MB, etc.
unsigned int NgapRequestHandler::d_cmr_cache_purge_items = 20;
 
bool NgapRequestHandler::d_use_cmr_cache = false;
MemoryCache<std::string> NgapRequestHandler::d_cmr_mem_cache;
 
// DMR++ caching
unsigned int NgapRequestHandler::d_dmrpp_mem_cache_size_items = 100;
unsigned int NgapRequestHandler::d_dmrpp_mem_cache_purge_items = 20;
 
bool NgapRequestHandler::d_use_dmrpp_cache = false;
MemoryCache<std::string> NgapRequestHandler::d_dmrpp_mem_cache;
 
long long NgapRequestHandler::d_dmrpp_file_cache_size_mb = 10'000;    // 10,000 MB ~= 10GB, roughly
long long NgapRequestHandler::d_dmrpp_file_cache_purge_size_mb = 2'000;  // 2,000 MB ~= 2GB
string NgapRequestHandler::d_dmrpp_file_cache_dir = "/tmp/hyrax_dmrpp_cache";
 
FileCache NgapRequestHandler::d_dmrpp_file_cache;
 
NgapRequestHandler::NgapRequestHandler(const string &name) :
        BESRequestHandler(name)
{
    add_method(VERS_RESPONSE, NgapRequestHandler::ngap_build_vers);
    add_method(HELP_RESPONSE, NgapRequestHandler::ngap_build_help);
 
    // Read BES keys to determine if the caches should be used. jhrg 9/22/23
    NgapRequestHandler::d_use_cmr_cache 
        = TheBESKeys::read_bool_key(USE_CMR_CACHE, NgapRequestHandler::d_use_cmr_cache);
    if (NgapRequestHandler::d_use_cmr_cache) {
        NgapRequestHandler::d_cmr_cache_size_items
                = TheBESKeys::read_int_key(CMR_CACHE_THRESHOLD, NgapRequestHandler::d_cmr_cache_size_items);
        NgapRequestHandler::d_cmr_cache_purge_items
                = TheBESKeys::read_int_key(CMR_CACHE_SPACE, NgapRequestHandler::d_cmr_cache_purge_items);
        if (!d_cmr_mem_cache.initialize(d_cmr_cache_size_items, d_cmr_cache_purge_items)) {
            ERROR_LOG("NgapRequestHandler::NgapRequestHandler() - failed to initialize CMR cache");
        }
    }
 
    NgapRequestHandler::d_use_dmrpp_cache
            = TheBESKeys::read_bool_key(USE_DMRPP_CACHE, NgapRequestHandler::d_use_dmrpp_cache);
    if (NgapRequestHandler::d_use_dmrpp_cache) {
        NgapRequestHandler::d_dmrpp_mem_cache_size_items
                = TheBESKeys::read_int_key(DMRPP_CACHE_THRESHOLD,  NgapRequestHandler::d_dmrpp_mem_cache_size_items);
        NgapRequestHandler::d_dmrpp_mem_cache_purge_items
                = TheBESKeys::read_int_key(DMRPP_CACHE_SPACE, NgapRequestHandler::d_dmrpp_mem_cache_purge_items);
        if (!d_dmrpp_mem_cache.initialize(d_dmrpp_mem_cache_size_items, d_dmrpp_mem_cache_purge_items)) {
            ERROR_LOG("NgapRequestHandler::NgapRequestHandler() - failed to initialize DMR++ cache");
        }
 
        // Now set up the file cache. Note that the sizes in the bes.conf file are in MB,
        // so convert them to bytes. jhrg 11/14/23
        NgapRequestHandler::d_dmrpp_file_cache_size_mb
            = MEGABYTE * TheBESKeys::read_ulong_key(DMRPP_FILE_CACHE_THRESHOLD,
                                                               NgapRequestHandler::d_dmrpp_file_cache_size_mb);
        NgapRequestHandler::d_dmrpp_file_cache_purge_size_mb
            = MEGABYTE * TheBESKeys::read_ulong_key(DMRPP_FILE_CACHE_SPACE,
                                                               NgapRequestHandler::d_dmrpp_file_cache_purge_size_mb);
        NgapRequestHandler::d_dmrpp_file_cache_dir
            = TheBESKeys::read_string_key(DMRPP_FILE_CACHE_DIR,
                                                     NgapRequestHandler::d_dmrpp_file_cache_dir);
        if (BESUtil::mkdir_p(NgapRequestHandler::d_dmrpp_file_cache_dir, 0775) != 0) {
            ERROR_LOG("DMR++ file cache directory '" + NgapRequestHandler::d_dmrpp_file_cache_dir + "' error: "
                      + strerror(errno));
        }
        if (!NgapRequestHandler::d_dmrpp_file_cache.initialize(NgapRequestHandler::d_dmrpp_file_cache_dir,
                                                               NgapRequestHandler::d_dmrpp_file_cache_size_mb,
                                                               NgapRequestHandler::d_dmrpp_file_cache_purge_size_mb)) {
            ERROR_LOG("NgapRequestHandler::NgapRequestHandler() - failed to initialize DMR++ file cache");
        }
    }
}
 
bool NgapRequestHandler::ngap_build_vers(BESDataHandlerInterface &dhi)
{
    auto info = dynamic_cast<BESVersionInfo *>(dhi.response_handler->get_response_object());
    if (!info) throw InternalErr(__FILE__, __LINE__, "Expected a BESVersionInfo instance");
 
    info->add_module(MODULE_NAME, MODULE_VERSION);
    return true;
}
 
bool NgapRequestHandler::ngap_build_help(BESDataHandlerInterface &dhi)
{
    auto info = dynamic_cast<BESInfo *>(dhi.response_handler->get_response_object());
    if (!info) throw InternalErr(__FILE__, __LINE__, "Expected a BESInfo instance");
 
    // This is an example. If you had a help file you could load it like
    // this and if your handler handled the following responses.
    map<string, string, std::less<>> attrs;
    attrs["name"] = MODULE_NAME;
    attrs["version"] = MODULE_VERSION;
 
    list<string> services;
    BESServiceRegistry::TheRegistry()->services_handled(NGAP_NAME, services);
    if (!services.empty()) {
        string handles = BESUtil::implode(services, ',');
        attrs["handles"] = handles;
    }
    info->begin_tag("module", &attrs);
    info->end_tag("module");
 
    return true;
}
 
void NgapRequestHandler::dump(ostream &strm) const
{
    strm << BESIndent::LMarg << "NgapRequestHandler::dump - (" << (void *) this << ")" << endl;
    BESIndent::Indent();
    BESRequestHandler::dump(strm);
    BESIndent::UnIndent();
}