vpd-manager/src/manager.cpp

#include "config.h"

#include "manager.hpp"

#include "constants.hpp"
#include "exceptions.hpp"
#include "logger.hpp"
#include "parser.hpp"
#include "parser_factory.hpp"
#include "parser_interface.hpp"
#include "single_fab.hpp"
#include "types.hpp"
#include "utility/dbus_utility.hpp"
#include "utility/json_utility.hpp"
#include "utility/vpd_specific_utility.hpp"

#include <boost/asio/steady_timer.hpp>
#include <sdbusplus/bus/match.hpp>
#include <sdbusplus/message.hpp>

namespace vpd
{
Manager::Manager(
    const std::shared_ptr<boost::asio::io_context>& ioCon,
    const std::shared_ptr<sdbusplus::asio::dbus_interface>& iFace,
    const std::shared_ptr<sdbusplus::asio::connection>& asioConnection) :
    m_ioContext(ioCon), m_interface(iFace), m_asioConnection(asioConnection)
{
#ifdef IBM_SYSTEM
    if (!dbusUtility::isChassisPowerOn())
    {
        SingleFab l_singleFab;
        const int& l_rc = l_singleFab.singleFabImOverride();

        if (l_rc == constants::FAILURE)
        {
            throw std::runtime_error(
                std::string(__FUNCTION__) +
                " : Found an invalid system configuration. Needs manual intervention. BMC is being quiesced.");
        }
    }
#endif

    try
    {
        // For backward compatibility. Should be depricated.
        iFace->register_method(
            "WriteKeyword",
            [this](const sdbusplus::message::object_path i_path,
                   const std::string i_recordName, const std::string i_keyword,
                   const types::BinaryVector i_value) -> int {
                return this->updateKeyword(
                    i_path, std::make_tuple(i_recordName, i_keyword, i_value));
            });

        // Register methods under com.ibm.VPD.Manager interface
        iFace->register_method(
            "UpdateKeyword",
            [this](const types::Path i_vpdPath,
                   const types::WriteVpdParams i_paramsToWriteData) -> int {
                return this->updateKeyword(i_vpdPath, i_paramsToWriteData);
            });

        iFace->register_method(
            "WriteKeywordOnHardware",
            [this](const types::Path i_fruPath,
                   const types::WriteVpdParams i_paramsToWriteData) -> int {
                return this->updateKeywordOnHardware(i_fruPath,
                                                     i_paramsToWriteData);
            });

        iFace->register_method(
            "ReadKeyword",
            [this](const types::Path i_fruPath,
                   const types::ReadVpdParams i_paramsToReadData)
                -> types::DbusVariantType {
                return this->readKeyword(i_fruPath, i_paramsToReadData);
            });

        iFace->register_method(
            "CollectFRUVPD",
            [this](const sdbusplus::message::object_path& i_dbusObjPath) {
                this->collectSingleFruVpd(i_dbusObjPath);
            });

        iFace->register_method(
            "deleteFRUVPD",
            [this](const sdbusplus::message::object_path& i_dbusObjPath) {
                this->deleteSingleFruVpd(i_dbusObjPath);
            });

        iFace->register_method(
            "GetExpandedLocationCode",
            [this](const std::string& i_unexpandedLocationCode,
                   uint16_t& i_nodeNumber) -> std::string {
                return this->getExpandedLocationCode(i_unexpandedLocationCode,
                                                     i_nodeNumber);
            });

        iFace->register_method("GetFRUsByExpandedLocationCode",
                               [this](const std::string& i_expandedLocationCode)
                                   -> types::ListOfPaths {
                                   return this->getFrusByExpandedLocationCode(
                                       i_expandedLocationCode);
                               });

        iFace->register_method(
            "GetFRUsByUnexpandedLocationCode",
            [this](const std::string& i_unexpandedLocationCode,
                   uint16_t& i_nodeNumber) -> types::ListOfPaths {
                return this->getFrusByUnexpandedLocationCode(
                    i_unexpandedLocationCode, i_nodeNumber);
            });

        iFace->register_method(
            "GetHardwarePath",
            [this](const sdbusplus::message::object_path& i_dbusObjPath)
                -> std::string { return this->getHwPath(i_dbusObjPath); });

        iFace->register_method("PerformVPDRecollection", [this]() {
            this->performVpdRecollection();
        });

        // Indicates FRU VPD collection for the system has not started.
        iFace->register_property_rw<std::string>(
            "CollectionStatus", sdbusplus::vtable::property_::emits_change,
            [this](const std::string l_currStatus, const auto&) {
                m_vpdCollectionStatus = l_currStatus;
                return 0;
            },
            [this](const auto&) { return m_vpdCollectionStatus; });

        // If required, instantiate OEM specific handler here.
#ifdef IBM_SYSTEM
        m_ibmHandler = std::make_shared<IbmHandler>(
            m_worker, m_backupAndRestoreObj, m_interface, m_ioContext,
            m_asioConnection);

        // TODO: Move to respective handler class as this is OEM specific. To
        // move this, collect single FRU VPD API needs to be modified. set
        // callback to detect host state change.
        registerHostStateChangeCallback();
#else
        m_worker = std::make_shared<Worker>(INVENTORY_JSON_DEFAULT);
        m_interface->set_property("CollectionStatus", std::string("Completed"));
#endif
    }
    catch (const std::exception& e)
    {
        logging::logMessage(
            "Manager class instantiation failed. " + std::string(e.what()));

        vpd::EventLogger::createSyncPel(
            vpd::EventLogger::getErrorType(e), vpd::types::SeverityType::Error,
            __FILE__, __FUNCTION__, 0, vpd::EventLogger::getErrorMsg(e),
            std::nullopt, std::nullopt, std::nullopt, std::nullopt);
    }
}

int Manager::updateKeyword(const types::Path i_vpdPath,
                           const types::WriteVpdParams i_paramsToWriteData)
{
    if (i_vpdPath.empty())
    {
        logging::logMessage("Given VPD path is empty.");
        return -1;
    }

    types::Path l_fruPath;
    nlohmann::json l_sysCfgJsonObj{};

    if (m_worker.get() != nullptr)
    {
        l_sysCfgJsonObj = m_worker->getSysCfgJsonObj();

        // Get the EEPROM path
        if (!l_sysCfgJsonObj.empty())
        {
            l_fruPath =
                jsonUtility::getFruPathFromJson(l_sysCfgJsonObj, i_vpdPath);
        }
    }

    if (l_fruPath.empty())
    {
        l_fruPath = i_vpdPath;
    }

    try
    {
        std::shared_ptr<Parser> l_parserObj =
            std::make_shared<Parser>(l_fruPath, l_sysCfgJsonObj);
        auto l_rc = l_parserObj->updateVpdKeyword(i_paramsToWriteData);

        if (l_rc != constants::FAILURE && m_backupAndRestoreObj)
        {
            if (m_backupAndRestoreObj->updateKeywordOnPrimaryOrBackupPath(
                    l_fruPath, i_paramsToWriteData) < constants::VALUE_0)
            {
                logging::logMessage(
                    "Write success, but backup and restore failed for file[" +
                    l_fruPath + "]");
            }
        }
        return l_rc;
    }
    catch (const std::exception& l_exception)
    {
        // TODO:: error log needed
        logging::logMessage("Update keyword failed for file[" + i_vpdPath +
                            "], reason: " + std::string(l_exception.what()));
        return -1;
    }
}

int Manager::updateKeywordOnHardware(
    const types::Path i_fruPath,
    const types::WriteVpdParams i_paramsToWriteData) noexcept
{
    try
    {
        if (i_fruPath.empty())
        {
            throw std::runtime_error("Given FRU path is empty");
        }

        nlohmann::json l_sysCfgJsonObj{};

        if (m_worker.get() != nullptr)
        {
            l_sysCfgJsonObj = m_worker->getSysCfgJsonObj();
        }

        std::shared_ptr<Parser> l_parserObj =
            std::make_shared<Parser>(i_fruPath, l_sysCfgJsonObj);
        return l_parserObj->updateVpdKeywordOnHardware(i_paramsToWriteData);
    }
    catch (const std::exception& l_exception)
    {
        EventLogger::createAsyncPel(
            types::ErrorType::InvalidEeprom, types::SeverityType::Informational,
            __FILE__, __FUNCTION__, 0,
            "Update keyword on hardware failed for file[" + i_fruPath +
                "], reason: " + std::string(l_exception.what()),
            std::nullopt, std::nullopt, std::nullopt, std::nullopt);

        return constants::FAILURE;
    }
}

types::DbusVariantType Manager::readKeyword(
    const types::Path i_fruPath, const types::ReadVpdParams i_paramsToReadData)
{
    try
    {
        nlohmann::json l_jsonObj{};

        if (m_worker.get() != nullptr)
        {
            l_jsonObj = m_worker->getSysCfgJsonObj();
        }

        std::error_code ec;

        // Check if given path is filesystem path
        if (!std::filesystem::exists(i_fruPath, ec) && (ec))
        {
            throw std::runtime_error(
                "Given file path " + i_fruPath + " not found.");
        }

        logging::logMessage("Performing VPD read on " + i_fruPath);

        std::shared_ptr<vpd::Parser> l_parserObj =
            std::make_shared<vpd::Parser>(i_fruPath, l_jsonObj);

        std::shared_ptr<vpd::ParserInterface> l_vpdParserInstance =
            l_parserObj->getVpdParserInstance();

        return (
            l_vpdParserInstance->readKeywordFromHardware(i_paramsToReadData));
    }
    catch (const std::exception& e)
    {
        logging::logMessage(
            e.what() + std::string(". VPD manager read operation failed for ") +
            i_fruPath);
        throw types::DeviceError::ReadFailure();
    }
}

void Manager::collectSingleFruVpd(
    const sdbusplus::message::object_path& i_dbusObjPath)
{
    try
    {
        if (m_vpdCollectionStatus != "Completed")
        {
            logging::logMessage(
                "Currently VPD CollectionStatus is not completed. Cannot perform single FRU VPD collection for " +
                std::string(i_dbusObjPath));
            return;
        }

        // Get system config JSON object from worker class
        nlohmann::json l_sysCfgJsonObj{};

        if (m_worker.get() != nullptr)
        {
            l_sysCfgJsonObj = m_worker->getSysCfgJsonObj();
        }

        // Check if system config JSON is present
        if (l_sysCfgJsonObj.empty())
        {
            logging::logMessage(
                "System config JSON object not present. Single FRU VPD collection is not performed for " +
                std::string(i_dbusObjPath));
            return;
        }

        // Get FRU path for the given D-bus object path from JSON
        const std::string& l_fruPath =
            jsonUtility::getFruPathFromJson(l_sysCfgJsonObj, i_dbusObjPath);

        if (l_fruPath.empty())
        {
            logging::logMessage(
                "D-bus object path not present in JSON. Single FRU VPD collection is not performed for " +
                std::string(i_dbusObjPath));
            return;
        }

        // Check if host is up and running
        if (dbusUtility::isHostRunning())
        {
            if (!jsonUtility::isFruReplaceableAtRuntime(l_sysCfgJsonObj,
                                                        l_fruPath))
            {
                logging::logMessage(
                    "Given FRU is not replaceable at host runtime. Single FRU VPD collection is not performed for " +
                    std::string(i_dbusObjPath));
                return;
            }
        }
        else if (dbusUtility::isBMCReady())
        {
            if (!jsonUtility::isFruReplaceableAtStandby(l_sysCfgJsonObj,
                                                        l_fruPath) &&
                (!jsonUtility::isFruReplaceableAtRuntime(l_sysCfgJsonObj,
                                                         l_fruPath)))
            {
                logging::logMessage(
                    "Given FRU is neither replaceable at standby nor replaceable at runtime. Single FRU VPD collection is not performed for " +
                    std::string(i_dbusObjPath));
                return;
            }
        }

        // Set CollectionStatus as InProgress. Since it's an intermediate state
        // D-bus set-property call is good enough to update the status.
        const std::string& l_collStatusProp = "CollectionStatus";

        if (!dbusUtility::writeDbusProperty(
                jsonUtility::getServiceName(l_sysCfgJsonObj,
                                            std::string(i_dbusObjPath)),
                std::string(i_dbusObjPath), constants::vpdCollectionInterface,
                l_collStatusProp,
                types::DbusVariantType{constants::vpdCollectionInProgress}))
        {
            logging::logMessage(
                "Unable to set CollectionStatus as InProgress for " +
                std::string(i_dbusObjPath) +
                ". Continue single FRU VPD collection.");
        }

        // Parse VPD
        types::VPDMapVariant l_parsedVpd = m_worker->parseVpdFile(l_fruPath);

        // If l_parsedVpd is pointing to std::monostate
        if (l_parsedVpd.index() == 0)
        {
            throw std::runtime_error(
                "VPD parsing failed for " + std::string(i_dbusObjPath));
        }

        // Get D-bus object map from worker class
        types::ObjectMap l_dbusObjectMap;
        m_worker->populateDbus(l_parsedVpd, l_dbusObjectMap, l_fruPath);

        if (l_dbusObjectMap.empty())
        {
            throw std::runtime_error(
                "Failed to create D-bus object map. Single FRU VPD collection failed for " +
                std::string(i_dbusObjPath));
        }

        // Call PIM's Notify method
        if (!dbusUtility::callPIM(move(l_dbusObjectMap)))
        {
            throw std::runtime_error(
                "Notify PIM failed. Single FRU VPD collection failed for " +
                std::string(i_dbusObjPath));
        }
    }
    catch (const std::exception& l_error)
    {
        // Notify FRU's VPD CollectionStatus as Failure
        if (!dbusUtility::notifyFRUCollectionStatus(
                std::string(i_dbusObjPath), constants::vpdCollectionFailure))
        {
            logging::logMessage(
                "Call to PIM Notify method failed to update Collection status as Failure for " +
                std::string(i_dbusObjPath));
        }

        // TODO: Log PEL
        logging::logMessage(std::string(l_error.what()));
    }
}

void Manager::deleteSingleFruVpd(
    const sdbusplus::message::object_path& i_dbusObjPath)
{
    try
    {
        if (std::string(i_dbusObjPath).empty())
        {
            throw std::runtime_error(
                "Given DBus object path is empty. Aborting FRU VPD deletion.");
        }

        if (m_worker.get() == nullptr)
        {
            throw std::runtime_error(
                "Worker object not found, can't perform FRU VPD deletion for: " +
                std::string(i_dbusObjPath));
        }

        m_worker->deleteFruVpd(std::string(i_dbusObjPath));
    }
    catch (const std::exception& l_ex)
    {
        // TODO: Log PEL
        logging::logMessage(l_ex.what());
    }
}

bool Manager::isValidUnexpandedLocationCode(
    const std::string& i_unexpandedLocationCode)
{
    if ((i_unexpandedLocationCode.length() <
         constants::UNEXP_LOCATION_CODE_MIN_LENGTH) ||
        ((i_unexpandedLocationCode.compare(0, 4, "Ufcs") !=
          constants::STR_CMP_SUCCESS) &&
         (i_unexpandedLocationCode.compare(0, 4, "Umts") !=
          constants::STR_CMP_SUCCESS)) ||
        ((i_unexpandedLocationCode.length() >
          constants::UNEXP_LOCATION_CODE_MIN_LENGTH) &&
         (i_unexpandedLocationCode.find("-") != 4)))
    {
        return false;
    }

    return true;
}

std::string Manager::getExpandedLocationCode(
    const std::string& i_unexpandedLocationCode,
    [[maybe_unused]] const uint16_t i_nodeNumber)
{
    if (!isValidUnexpandedLocationCode(i_unexpandedLocationCode))
    {
        phosphor::logging::elog<types::DbusInvalidArgument>(
            types::InvalidArgument::ARGUMENT_NAME("LOCATIONCODE"),
            types::InvalidArgument::ARGUMENT_VALUE(
                i_unexpandedLocationCode.c_str()));
    }

    const nlohmann::json& l_sysCfgJsonObj = m_worker->getSysCfgJsonObj();
    if (!l_sysCfgJsonObj.contains("frus"))
    {
        logging::logMessage("Missing frus tag in system config JSON");
    }

    const nlohmann::json& l_listOfFrus =
        l_sysCfgJsonObj["frus"].get_ref<const nlohmann::json::object_t&>();

    for (const auto& l_frus : l_listOfFrus.items())
    {
        for (const auto& l_aFru : l_frus.value())
        {
            if (l_aFru["extraInterfaces"].contains(
                    constants::locationCodeInf) &&
                l_aFru["extraInterfaces"][constants::locationCodeInf].value(
                    "LocationCode", "") == i_unexpandedLocationCode)
            {
                return std::get<std::string>(dbusUtility::readDbusProperty(
                    l_aFru["serviceName"], l_aFru["inventoryPath"],
                    constants::locationCodeInf, "LocationCode"));
            }
        }
    }
    phosphor::logging::elog<types::DbusInvalidArgument>(
        types::InvalidArgument::ARGUMENT_NAME("LOCATIONCODE"),
        types::InvalidArgument::ARGUMENT_VALUE(
            i_unexpandedLocationCode.c_str()));
}

types::ListOfPaths Manager::getFrusByUnexpandedLocationCode(
    const std::string& i_unexpandedLocationCode,
    [[maybe_unused]] const uint16_t i_nodeNumber)
{
    types::ListOfPaths l_inventoryPaths;

    if (!isValidUnexpandedLocationCode(i_unexpandedLocationCode))
    {
        phosphor::logging::elog<types::DbusInvalidArgument>(
            types::InvalidArgument::ARGUMENT_NAME("LOCATIONCODE"),
            types::InvalidArgument::ARGUMENT_VALUE(
                i_unexpandedLocationCode.c_str()));
    }

    const nlohmann::json& l_sysCfgJsonObj = m_worker->getSysCfgJsonObj();
    if (!l_sysCfgJsonObj.contains("frus"))
    {
        logging::logMessage("Missing frus tag in system config JSON");
    }

    const nlohmann::json& l_listOfFrus =
        l_sysCfgJsonObj["frus"].get_ref<const nlohmann::json::object_t&>();

    for (const auto& l_frus : l_listOfFrus.items())
    {
        for (const auto& l_aFru : l_frus.value())
        {
            if (l_aFru["extraInterfaces"].contains(
                    constants::locationCodeInf) &&
                l_aFru["extraInterfaces"][constants::locationCodeInf].value(
                    "LocationCode", "") == i_unexpandedLocationCode)
            {
                l_inventoryPaths.push_back(
                    l_aFru.at("inventoryPath")
                        .get_ref<const nlohmann::json::string_t&>());
            }
        }
    }

    if (l_inventoryPaths.empty())
    {
        phosphor::logging::elog<types::DbusInvalidArgument>(
            types::InvalidArgument::ARGUMENT_NAME("LOCATIONCODE"),
            types::InvalidArgument::ARGUMENT_VALUE(
                i_unexpandedLocationCode.c_str()));
    }

    return l_inventoryPaths;
}

std::string Manager::getHwPath(
    const sdbusplus::message::object_path& i_dbusObjPath)
{
    // Dummy code to supress unused variable warning. To be removed.
    logging::logMessage(std::string(i_dbusObjPath));

    return std::string{};
}

std::tuple<std::string, uint16_t> Manager::getUnexpandedLocationCode(
    const std::string& i_expandedLocationCode)
{
    /**
     * Location code should always start with U and fulfil minimum length
     * criteria.
     */
    if (i_expandedLocationCode[0] != 'U' ||
        i_expandedLocationCode.length() <
            constants::EXP_LOCATION_CODE_MIN_LENGTH)
    {
        phosphor::logging::elog<types::DbusInvalidArgument>(
            types::InvalidArgument::ARGUMENT_NAME("LOCATIONCODE"),
            types::InvalidArgument::ARGUMENT_VALUE(
                i_expandedLocationCode.c_str()));
    }

    std::string l_fcKwd;

    auto l_fcKwdValue = dbusUtility::readDbusProperty(
        "xyz.openbmc_project.Inventory.Manager",
        "/xyz/openbmc_project/inventory/system/chassis/motherboard",
        "com.ibm.ipzvpd.VCEN", "FC");

    if (auto l_kwdValue = std::get_if<types::BinaryVector>(&l_fcKwdValue))
    {
        l_fcKwd.assign(l_kwdValue->begin(), l_kwdValue->end());
    }

    // Get the first part of expanded location code to check for FC or TM.
    std::string l_firstKwd = i_expandedLocationCode.substr(1, 4);

    std::string l_unexpandedLocationCode{};
    uint16_t l_nodeNummber = constants::INVALID_NODE_NUMBER;

    // Check if this value matches the value of FC keyword.
    if (l_fcKwd.substr(0, 4) == l_firstKwd)
    {
        /**
         * Period(.) should be there in expanded location code to seggregate
         * FC, node number and SE values.
         */
        size_t l_nodeStartPos = i_expandedLocationCode.find('.');
        if (l_nodeStartPos == std::string::npos)
        {
            phosphor::logging::elog<types::DbusInvalidArgument>(
                types::InvalidArgument::ARGUMENT_NAME("LOCATIONCODE"),
                types::InvalidArgument::ARGUMENT_VALUE(
                    i_expandedLocationCode.c_str()));
        }

        size_t l_nodeEndPos =
            i_expandedLocationCode.find('.', l_nodeStartPos + 1);
        if (l_nodeEndPos == std::string::npos)
        {
            phosphor::logging::elog<types::DbusInvalidArgument>(
                types::InvalidArgument::ARGUMENT_NAME("LOCATIONCODE"),
                types::InvalidArgument::ARGUMENT_VALUE(
                    i_expandedLocationCode.c_str()));
        }

        // Skip 3 bytes for '.ND'
        l_nodeNummber = std::stoi(i_expandedLocationCode.substr(
            l_nodeStartPos + 3, (l_nodeEndPos - l_nodeStartPos - 3)));

        /**
         * Confirm if there are other details apart FC, node number and SE
         * in location code
         */
        if (i_expandedLocationCode.length() >
            constants::EXP_LOCATION_CODE_MIN_LENGTH)
        {
            l_unexpandedLocationCode =
                i_expandedLocationCode[0] + std::string("fcs") +
                i_expandedLocationCode.substr(
                    l_nodeEndPos + 1 + constants::SE_KWD_LENGTH,
                    std::string::npos);
        }
        else
        {
            l_unexpandedLocationCode = "Ufcs";
        }
    }
    else
    {
        std::string l_tmKwd;
        // Read TM keyword value.
        auto l_tmKwdValue = dbusUtility::readDbusProperty(
            "xyz.openbmc_project.Inventory.Manager",
            "/xyz/openbmc_project/inventory/system/chassis/motherboard",
            "com.ibm.ipzvpd.VSYS", "TM");

        if (auto l_kwdValue = std::get_if<types::BinaryVector>(&l_tmKwdValue))
        {
            l_tmKwd.assign(l_kwdValue->begin(), l_kwdValue->end());
        }

        // Check if the substr matches to TM keyword value.
        if (l_tmKwd.substr(0, 4) == l_firstKwd)
        {
            /**
             * System location code will not have node number and any other
             * details.
             */
            l_unexpandedLocationCode = "Umts";
        }
        // The given location code is neither "fcs" or "mts".
        else
        {
            phosphor::logging::elog<types::DbusInvalidArgument>(
                types::InvalidArgument::ARGUMENT_NAME("LOCATIONCODE"),
                types::InvalidArgument::ARGUMENT_VALUE(
                    i_expandedLocationCode.c_str()));
        }
    }

    return std::make_tuple(l_unexpandedLocationCode, l_nodeNummber);
}

types::ListOfPaths Manager::getFrusByExpandedLocationCode(
    const std::string& i_expandedLocationCode)
{
    std::tuple<std::string, uint16_t> l_locationAndNodePair =
        getUnexpandedLocationCode(i_expandedLocationCode);

    return getFrusByUnexpandedLocationCode(std::get<0>(l_locationAndNodePair),
                                           std::get<1>(l_locationAndNodePair));
}

void Manager::registerHostStateChangeCallback()
{
    static std::shared_ptr<sdbusplus::bus::match_t> l_hostState =
        std::make_shared<sdbusplus::bus::match_t>(
            *m_asioConnection,
            sdbusplus::bus::match::rules::propertiesChanged(
                constants::hostObjectPath, constants::hostInterface),
            [this](sdbusplus::message_t& i_msg) {
                hostStateChangeCallBack(i_msg);
            });
}

void Manager::hostStateChangeCallBack(sdbusplus::message_t& i_msg)
{
    try
    {
        if (i_msg.is_method_error())
        {
            throw std::runtime_error(
                "Error reading callback message for host state");
        }

        std::string l_objectPath;
        types::PropertyMap l_propMap;
        i_msg.read(l_objectPath, l_propMap);

        const auto l_itr = l_propMap.find("CurrentHostState");

        if (l_itr == l_propMap.end())
        {
            throw std::runtime_error(
                "CurrentHostState field is missing in callback message");
        }

        if (auto l_hostState = std::get_if<std::string>(&(l_itr->second)))
        {
            // implies system is moving from standby to power on state
            if (*l_hostState == "xyz.openbmc_project.State.Host.HostState."
                                "TransitioningToRunning")
            {
                // TODO: check for all the essential FRUs in the system.

                // Perform recollection.
                performVpdRecollection();
                return;
            }
        }
        else
        {
            throw std::runtime_error(
                "Invalid type recieved in variant for host state.");
        }
    }
    catch (const std::exception& l_ex)
    {
        // TODO: Log PEL.
        logging::logMessage(l_ex.what());
    }
}

void Manager::performVpdRecollection()
{
    try
    {
        if (m_worker.get() != nullptr)
        {
            nlohmann::json l_sysCfgJsonObj = m_worker->getSysCfgJsonObj();

            // Check if system config JSON is present
            if (l_sysCfgJsonObj.empty())
            {
                throw std::runtime_error(
                    "System config json object is empty, can't process recollection.");
            }

            const auto& l_frusReplaceableAtStandby =
                jsonUtility::getListOfFrusReplaceableAtStandby(l_sysCfgJsonObj);

            for (const auto& l_fruInventoryPath : l_frusReplaceableAtStandby)
            {
                // ToDo: Add some logic/trace to know the flow to
                // collectSingleFruVpd has been directed via
                // performVpdRecollection.
                collectSingleFruVpd(l_fruInventoryPath);
            }
            return;
        }

        throw std::runtime_error(
            "Worker object not found can't process recollection");
    }
    catch (const std::exception& l_ex)
    {
        // TODO Log PEL
        logging::logMessage(
            "VPD recollection failed with error: " + std::string(l_ex.what()));
    }
}
} // namespace vpd