mythbackend_main_helpers.cpp

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#include "libmythbase/mythconfig.h"
#if CONFIG_SYSTEMD_NOTIFY
#include <systemd/sd-daemon.h>
static inline void be_sd_notify(const char *str) { sd_notify(0, str); };
#else
static inline void be_sd_notify(const char */*str*/) {};
#endif
 
// C++ headers
#include <cerrno>
#include <csignal>
#include <cstdlib>
#include <fcntl.h>
#include <sys/stat.h>
#include <sys/time.h>     // for setpriority
#include <sys/types.h>
#include <unistd.h>
 
// Qt
#include <QtGlobal>
#include <QCoreApplication>
#include <QFileInfo>
#include <QFile>
#include <QDir>
#include <QMap>
 
// MythTV
#include "libmythbase/compat.h"
#include "libmythbase/dbutil.h"
#include "libmythbase/exitcodes.h"
#include "libmythbase/hardwareprofile.h"
#include "libmythbase/mythcorecontext.h"
#include "libmythbase/mythdb.h"
#include "libmythbase/mythlogging.h"
#include "libmythbase/mythtimezone.h"
#include "libmythbase/mythtranslation.h"
#include "libmythbase/mythversion.h"
#include "libmythbase/storagegroup.h"
#include "libmythtv/dbcheck.h"
#include "libmythtv/eitcache.h"
#include "libmythtv/jobqueue.h"
#include "libmythtv/mythsystemevent.h"
#include "libmythtv/previewgenerator.h"
#include "libmythtv/programinfo.h"
#include "libmythtv/scheduledrecording.h"
#include "libmythtv/tv_rec.h"
#include "libmythupnp/ssdp.h"
#include "libmythupnp/taskqueue.h"
 
// MythBackend
#include "autoexpire.h"
#include "backendcontext.h"
#include "backendhousekeeper.h"
#include "encoderlink.h"
#include "httpstatus.h"
#include "mainserver.h"
#include "mediaserver.h"
#include "mythbackend_commandlineparser.h"
#include "mythbackend_main_helpers.h"
#include "scheduler.h"
 
// New webserver
#include "libmythbase/http/mythhttproot.h"
#include "libmythbase/http/mythhttprewrite.h"
#include "libmythbase/http/mythhttpinstance.h"
#include "servicesv2/v2myth.h"
#include "servicesv2/v2video.h"
#include "servicesv2/v2dvr.h"
#include "servicesv2/v2content.h"
#include "servicesv2/v2guide.h"
#include "servicesv2/v2channel.h"
#include "servicesv2/v2status.h"
#include "servicesv2/v2capture.h"
#include "servicesv2/v2music.h"
#include "servicesv2/v2config.h"
 
#define LOC      QString("MythBackend: ")
#define LOC_WARN QString("MythBackend, Warning: ")
#define LOC_ERR  QString("MythBackend, Error: ")
 
static HouseKeeper            *gHousekeeping    { nullptr };
static JobQueue               *gJobQueue        { nullptr };
static MythSystemEventHandler *gSysEventHandler { nullptr };
static MediaServer            *g_pUPnp          { nullptr };
static MainServer             *mainServer       { nullptr };
 
bool setupTVs(bool ismaster, bool &error)
{
    error = false;
    QString localhostname = gCoreContext->GetHostName();
 
    MSqlQuery query(MSqlQuery::InitCon());
 
    if (ismaster)
    {
        // Hack to make sure recorded.basename gets set if the user
        // downgrades to a prior version and creates new entries
        // without it.
        if (!query.exec("UPDATE recorded SET basename = CONCAT(chanid, '_', "
                        "DATE_FORMAT(starttime, '%Y%m%d%H%i00'), '_', "
                        "DATE_FORMAT(endtime, '%Y%m%d%H%i00'), '.nuv') "
                        "WHERE basename = '';"))
            MythDB::DBError("Updating record basename", query);
 
        // Hack to make sure record.station gets set if the user
        // downgrades to a prior version and creates new entries
        // without it.
        if (!query.exec("UPDATE channel SET callsign=chanid "
                        "WHERE callsign IS NULL OR callsign='';"))
            MythDB::DBError("Updating channel callsign", query);
 
        if (query.exec("SELECT MIN(chanid) FROM channel;"))
        {
            query.first();
            int min_chanid = query.value(0).toInt();
            if (!query.exec(QString("UPDATE record SET chanid = %1 "
                                    "WHERE chanid IS NULL;").arg(min_chanid)))
                MythDB::DBError("Updating record chanid", query);
        }
        else
        {
            MythDB::DBError("Querying minimum chanid", query);
        }
 
        MSqlQuery records_without_station(MSqlQuery::InitCon());
        records_without_station.prepare("SELECT record.chanid,"
                " channel.callsign FROM record LEFT JOIN channel"
                " ON record.chanid = channel.chanid WHERE record.station='';");
        if (records_without_station.exec())
        {
            MSqlQuery update_record(MSqlQuery::InitCon());
            update_record.prepare("UPDATE record SET station = :CALLSIGN"
                    " WHERE chanid = :CHANID;");
            while (records_without_station.next())
            {
                update_record.bindValue(":CALLSIGN",
                        records_without_station.value(1));
                update_record.bindValue(":CHANID",
                        records_without_station.value(0));
                if (!update_record.exec())
                {
                    MythDB::DBError("Updating record station", update_record);
                }
            }
        }
    }
 
    if (!query.exec(
            "SELECT cardid, parentid, videodevice, hostname, sourceid "
            "FROM capturecard "
            "ORDER BY cardid"))
    {
        MythDB::DBError("Querying Recorders", query);
        return false;
    }
 
    std::vector<unsigned int> cardids;
    std::vector<QString> hosts;
    while (query.next())
    {
        uint    cardid      = query.value(0).toUInt();
        uint    parentid    = query.value(1).toUInt();
        QString videodevice = query.value(2).toString();
        QString hostname    = query.value(3).toString();
        uint    sourceid    = query.value(4).toUInt();
        QString cidmsg      = QString("Card[%1](%2)").arg(cardid).arg(videodevice);
 
        if (hostname.isEmpty())
        {
            LOG(VB_GENERAL, LOG_ERR, cidmsg +
                " does not have a hostname defined.\n"
                "Please run setup and confirm all of the capture cards.\n");
            continue;
        }
 
        // Skip all cards that do not have a video source
        if (sourceid == 0)
        {
            if (parentid == 0)
            {
                LOG(VB_GENERAL, LOG_WARNING, cidmsg +
                    " does not have a video source");
            }
            continue;
        }
 
        cardids.push_back(cardid);
        hosts.push_back(hostname);
    }
 
    QWriteLocker tvlocker(&TVRec::s_inputsLock);
 
    // NOLINTNEXTLINE(clang-analyzer-cplusplus.NewDeleteLeaks)
    for (size_t i = 0; i < cardids.size(); i++)
    {
        if (hosts[i] == localhostname) {
            // No memory leak. The constructor for TVRec adds the item
            // to the static map TVRec::s_inputs.
            new TVRec(cardids[i]);
        }
    }
 
    for (size_t i = 0; i < cardids.size(); i++)
    {
        uint    cardid = cardids[i];
        const QString& host   = hosts[i];
        QString cidmsg = QString("Card %1").arg(cardid);
 
        if (!ismaster)
        {
            if (host == localhostname)
            {
                TVRec *tv = TVRec::GetTVRec(cardid);
                if (tv && tv->Init())
                {
                    auto *enc = new EncoderLink(cardid, tv);
                    gTVList[cardid] = enc;
                }
                else
                {
                    LOG(VB_GENERAL, LOG_ERR, "Problem with capture cards. " +
                            cidmsg + " failed init");
                    delete tv;
                    // No longer set an error here, because we need the
                    // slave backend to be able to start without a capture
                    // card, so that it can be setup through the web app
                }
            }
        }
        else
        {
            if (host == localhostname)
            {
                TVRec *tv = TVRec::GetTVRec(cardid);
                if (tv && tv->Init())
                {
                    auto *enc = new EncoderLink(cardid, tv);
                    gTVList[cardid] = enc;
                }
                else
                {
                    LOG(VB_GENERAL, LOG_ERR, "Problem with capture cards. " +
                            cidmsg + " failed init");
                    delete tv;
                }
            }
            else
            {
                auto *enc = new EncoderLink(cardid, nullptr, host);
                gTVList[cardid] = enc;
            }
        }
    }
 
    if (gTVList.empty())
    {
        LOG(VB_GENERAL, LOG_WARNING, LOC +
                "No valid capture cards are defined in the database.");
    }
 
    return true;
}
 
void cleanup(void)
{
    if (mainServer)
    {
        mainServer->Stop();
        qApp->processEvents();
    }
 
    if (gCoreContext)
        gCoreContext->SetExiting();
 
    delete gSysEventHandler;
    gSysEventHandler = nullptr;
 
    delete gHousekeeping;
    gHousekeeping = nullptr;
 
    if (gCoreContext)
    {
        delete gCoreContext->GetScheduler();
        gCoreContext->SetScheduler(nullptr);
    }
 
    delete gExpirer;
    gExpirer = nullptr;
 
    delete gJobQueue;
    gJobQueue = nullptr;
 
    delete g_pUPnp;
    g_pUPnp = nullptr;
 
    if (TaskQueue::Instance())
    {
        TaskQueue::Instance()->RequestTerminate();
        TaskQueue::Instance()->wait();
    }
 
    while (!TVRec::s_inputs.empty())
    {
        TVRec *rec = *TVRec::s_inputs.begin();
        delete rec;
    }
 
    delete mainServer;
    mainServer = nullptr;
 
     delete gBackendContext;
     gBackendContext = nullptr;
}
 
int handle_command(const MythBackendCommandLineParser &cmdline)
{
    if (cmdline.toBool("setverbose"))
    {
        if (gCoreContext->ConnectToMasterServer())
        {
            QString message = "SET_VERBOSE ";
            message += cmdline.toString("setverbose");
 
            gCoreContext->SendMessage(message);
            LOG(VB_GENERAL, LOG_INFO,
                QString("Sent '%1' message").arg(message));
            return GENERIC_EXIT_OK;
        }
        LOG(VB_GENERAL, LOG_ERR,
            "Unable to connect to backend, verbose mask unchanged ");
        return GENERIC_EXIT_CONNECT_ERROR;
    }
 
    if (cmdline.toBool("setloglevel"))
    {
        if (gCoreContext->ConnectToMasterServer())
        {
            QString message = "SET_LOG_LEVEL ";
            message += cmdline.toString("setloglevel");
 
            gCoreContext->SendMessage(message);
            LOG(VB_GENERAL, LOG_INFO,
                QString("Sent '%1' message").arg(message));
            return GENERIC_EXIT_OK;
        }
        LOG(VB_GENERAL, LOG_ERR,
            "Unable to connect to backend, log level unchanged ");
        return GENERIC_EXIT_CONNECT_ERROR;
    }
 
    if (cmdline.toBool("printsched") ||
        cmdline.toBool("testsched"))
    {
        auto *sched = new Scheduler(false, &gTVList);
        if (cmdline.toBool("printsched"))
        {
            if (!gCoreContext->ConnectToMasterServer())
            {
                LOG(VB_GENERAL, LOG_ERR, "Cannot connect to master");
                delete sched;
                return GENERIC_EXIT_CONNECT_ERROR;
            }
            std::cout << "Retrieving Schedule from Master backend.\n";
            sched->FillRecordListFromMaster();
        }
        else
        {
            std::cout << "Calculating Schedule from database.\n" <<
                         "Inputs, Card IDs, and Conflict info may be invalid "
                         "if you have multiple tuners.\n";
            ProgramInfo::CheckProgramIDAuthorities();
            sched->FillRecordListFromDB();
        }
 
        verboseMask |= VB_SCHEDULE;
        LogLevel_t oldLogLevel = logLevel;
        logLevel = LOG_DEBUG;
        sched->PrintList(true);
        logLevel = oldLogLevel;
        delete sched;
        return GENERIC_EXIT_OK;
    }
 
    if (cmdline.toBool("printexpire"))
    {
        gExpirer = new AutoExpire();
        gExpirer->PrintExpireList(cmdline.toString("printexpire"));
        return GENERIC_EXIT_OK;
    }
 
    // This should never actually be reached..
    return GENERIC_EXIT_OK;
}
using namespace MythTZ;
 
int connect_to_master(void)
{
    auto *tempMonitorConnection = new MythSocket();
    if (tempMonitorConnection->ConnectToHost(
            gCoreContext->GetMasterServerIP(),
            MythCoreContext::GetMasterServerPort()))
    {
        if (!gCoreContext->CheckProtoVersion(tempMonitorConnection))
        {
            LOG(VB_GENERAL, LOG_ERR, "Master backend is incompatible with "
                    "this backend.\nCannot become a slave.");
            tempMonitorConnection->DecrRef();
            return GENERIC_EXIT_CONNECT_ERROR;
        }
 
        QStringList tempMonitorDone("DONE");
 
        QStringList tempMonitorAnnounce(QString("ANN Monitor %1 0")
                                            .arg(gCoreContext->GetHostName()));
        tempMonitorConnection->SendReceiveStringList(tempMonitorAnnounce);
        if (tempMonitorAnnounce.empty() ||
            tempMonitorAnnounce[0] == "ERROR")
        {
            tempMonitorConnection->DecrRef();
            tempMonitorConnection = nullptr;
            if (tempMonitorAnnounce.empty())
            {
                LOG(VB_GENERAL, LOG_ERR, LOC +
                    "Failed to open event socket, timeout");
            }
            else
            {
                LOG(VB_GENERAL, LOG_ERR, LOC +
                    "Failed to open event socket" +
                    ((tempMonitorAnnounce.size() >= 2) ?
                    QString(", error was %1").arg(tempMonitorAnnounce[1]) :
                    QString(", remote error")));
            }
        }
 
        QStringList timeCheck;
        if (tempMonitorConnection)
        {
            timeCheck.push_back("QUERY_TIME_ZONE");
            tempMonitorConnection->SendReceiveStringList(timeCheck);
            tempMonitorConnection->WriteStringList(tempMonitorDone);
        }
        if (timeCheck.size() < 3)
        {
            if (tempMonitorConnection)
                tempMonitorConnection->DecrRef();
            return GENERIC_EXIT_SOCKET_ERROR;
        }
 
        QDateTime our_time = MythDate::current();
        QDateTime master_time = MythDate::fromString(timeCheck[2]);
        int timediff = abs(our_time.secsTo(master_time));
 
        if (timediff > 300)
        {
            LOG(VB_GENERAL, LOG_ERR,
                QString("Current time on the master backend differs by "
                        "%1 seconds from time on this system. Exiting.")
                .arg(timediff));
            if (tempMonitorConnection)
                tempMonitorConnection->DecrRef();
            return GENERIC_EXIT_INVALID_TIME;
        }
 
        if (timediff > 20)
        {
            LOG(VB_GENERAL, LOG_WARNING,
                    QString("Time difference between the master "
                            "backend and this system is %1 seconds.")
                .arg(timediff));
        }
    }
    if (tempMonitorConnection)
        tempMonitorConnection->DecrRef();
 
    return GENERIC_EXIT_OK;
}
 
 
void print_warnings(const MythBackendCommandLineParser &cmdline)
{
    if (cmdline.toBool("nohousekeeper"))
    {
        LOG(VB_GENERAL, LOG_WARNING, LOC +
            "****** The Housekeeper has been DISABLED with "
            "the --nohousekeeper option ******");
    }
    if (cmdline.toBool("nosched"))
    {
        LOG(VB_GENERAL, LOG_WARNING, LOC +
            "********** The Scheduler has been DISABLED with "
            "the --nosched option **********");
    }
    if (cmdline.toBool("noautoexpire"))
    {
        LOG(VB_GENERAL, LOG_WARNING, LOC +
            "********* Auto-Expire has been DISABLED with "
            "the --noautoexpire option ********");
    }
    if (cmdline.toBool("nojobqueue"))
    {
        LOG(VB_GENERAL, LOG_WARNING, LOC +
            "********* The JobQueue has been DISABLED with "
            "the --nojobqueue option *********");
    }
}
 
int run_backend(MythBackendCommandLineParser &cmdline)
{
    gBackendContext = new BackendContext();
 
    if (gCoreContext->IsDatabaseIgnored())
    {
        return run_setup_webserver();
    }
    if (!DBUtil::CheckTimeZoneSupport())
    {
        LOG(VB_GENERAL, LOG_ERR,
            "MySQL time zone support is missing.  "
            "Please install it and try again.  "
            "See 'mysql_tzinfo_to_sql' for assistance.");
        gCoreContext->GetDB()->IgnoreDatabase(true);
        V2Myth::s_WebOnlyStartup = V2Myth::kWebOnlyDBTimezone;
        return run_setup_webserver();
    }
    bool ismaster = gCoreContext->IsMasterHost();
 
    if (!UpgradeTVDatabaseSchema(ismaster, ismaster, true))
    {
        LOG(VB_GENERAL, LOG_ERR,
            QString("Couldn't upgrade database to new schema on %1 backend.")
            .arg(ismaster ? "master" : "slave"));
        V2Myth::s_WebOnlyStartup = V2Myth::kWebOnlySchemaUpdate;
        return run_setup_webserver();
    }
#ifndef NDEBUG
    if (cmdline.toBool("upgradedbonly"))
    {
        LOG(VB_GENERAL, LOG_ERR, "Exiting as requested.");
        return GENERIC_EXIT_OK;
    }
#endif
 
    be_sd_notify("STATUS=Loading translation");
    MythTranslation::load("mythfrontend");
 
    if (cmdline.toBool("webonly"))
    {
        V2Myth::s_WebOnlyStartup = V2Myth::kWebOnlyWebOnlyParm;
        return run_setup_webserver();
    }
    if (!ismaster)
    {
        be_sd_notify("STATUS=Connecting to master backend");
        int ret = connect_to_master();
        if (ret != GENERIC_EXIT_OK)
            return ret;
    }
 
    be_sd_notify("STATUS=Get backend server port");
    int     port = gCoreContext->GetBackendServerPort();
    if (gCoreContext->GetBackendServerIP().isEmpty())
    {
        std::cerr << "No setting found for this machine's BackendServerAddr.\n"
                  << "MythBackend starting in Web App only mode for initial setup.\n"
                  << "Use http://<yourBackend>:6544 to perform setup.\n";
        V2Myth::s_WebOnlyStartup = V2Myth::kWebOnlyIPAddress;
        return run_setup_webserver();
    }
 
    gSysEventHandler = new MythSystemEventHandler();
 
    if (ismaster)
    {
        LOG(VB_GENERAL, LOG_NOTICE, LOC + "Starting up as the master server.");
    }
    else
    {
        LOG(VB_GENERAL, LOG_NOTICE, LOC + "Running as a slave backend.");
    }
 
    if (ismaster)
    {
        EITCache::ClearChannelLocks();
    }
 
    print_warnings(cmdline);
 
    bool fatal_error = false;
    bool runsched = setupTVs(ismaster, fatal_error);
    if (fatal_error)
        return GENERIC_EXIT_SETUP_ERROR;
 
    Scheduler *sched = nullptr;
    if (ismaster)
    {
        if (runsched)
        {
            be_sd_notify("STATUS=Creating scheduler");
            sched = new Scheduler(true, &gTVList);
            int err = sched->GetError();
            if (err)
            {
                delete sched;
                return err;
            }
 
            if (cmdline.toBool("nosched"))
                sched->DisableScheduling();
        }
 
        if (!cmdline.toBool("noautoexpire"))
        {
            gExpirer = new AutoExpire(&gTVList);
            if (sched)
                sched->SetExpirer(gExpirer);
        }
        gCoreContext->SetScheduler(sched);
        ChannelGroup::UpdateChannelGroups();
    }
 
    if (!cmdline.toBool("nohousekeeper"))
    {
        be_sd_notify("STATUS=Creating housekeeper");
        gHousekeeping = new HouseKeeper();
 
        if (ismaster)
        {
            gHousekeeping->RegisterTask(new CleanupTask());
            gHousekeeping->RegisterTask(new ThemeUpdateTask());
            gHousekeeping->RegisterTask(new ArtworkTask());
            gHousekeeping->RegisterTask(new MythFillDatabaseTask());
 
            // only run this task if MythMusic is installed and we have a new enough schema
            if (gCoreContext->GetNumSetting("MusicDBSchemaVer", 0) >= 1024)
                gHousekeeping->RegisterTask(new RadioStreamUpdateTask());
        }
 
        gHousekeeping->RegisterTask(new JobQueueRecoverTask());
#ifdef Q_OS_LINUX
 #ifdef CONFIG_BINDINGS_PYTHON
        gHousekeeping->RegisterTask(new HardwareProfileTask());
 #endif
#endif
 
        gHousekeeping->Start();
    }
 
    if (!cmdline.toBool("nojobqueue"))
        gJobQueue = new JobQueue(ismaster);
 
    // ----------------------------------------------------------------------
    //
    // ----------------------------------------------------------------------
 
    if (g_pUPnp == nullptr)
    {
        be_sd_notify("STATUS=Creating UPnP media server");
        g_pUPnp = new MediaServer();
 
        g_pUPnp->Init(ismaster, cmdline.toBool("noupnp"));
    }
 
    if (cmdline.toBool("dvbv3"))
    {
        LOG(VB_GENERAL, LOG_INFO, LOC + "Use legacy DVBv3 API");
        gCoreContext->SetDVBv3(true);
    }
 
    // ----------------------------------------------------------------------
    // Setup status server
    // ----------------------------------------------------------------------
 
    HttpStatus *httpStatus = nullptr;
    HttpServer *pHS = g_pUPnp->GetHttpServer();
 
    if (pHS)
    {
        LOG(VB_GENERAL, LOG_INFO, "Main::Registering HttpStatus Extension");
        be_sd_notify("STATUS=Registering HttpStatus Extension");
 
        httpStatus = new HttpStatus( &gTVList, sched, ismaster );
        pHS->RegisterExtension( httpStatus );
    }
 
    be_sd_notify("STATUS=Creating main server");
    mainServer = new MainServer(
        ismaster, port, &gTVList, sched, gExpirer);
 
    int exitCode = mainServer->GetExitCode();
    if (exitCode != GENERIC_EXIT_OK)
    {
        LOG(VB_GENERAL, LOG_CRIT,
            "Backend exiting, MainServer initialization error.");
        cleanup();
        return exitCode;
    }
 
    if (httpStatus && mainServer)
        httpStatus->SetMainServer(mainServer);
 
    be_sd_notify("STATUS=Check all storage groups");
    StorageGroup::CheckAllStorageGroupDirs();
 
    be_sd_notify("STATUS=Sending \"master started\" message");
    if (gCoreContext->IsMasterBackend())
        gCoreContext->SendSystemEvent("MASTER_STARTED");
 
    // Provide systemd ready notification (for Type=notify)
    be_sd_notify("READY=1");
 
    const HTTPServices be_services = {
        { VIDEO_SERVICE, &MythHTTPService::Create<V2Video> },
        { MYTH_SERVICE, &MythHTTPService::Create<V2Myth> },
        { DVR_SERVICE, &MythHTTPService::Create<V2Dvr> },
        { CONTENT_SERVICE, &MythHTTPService::Create<V2Content> },
        { GUIDE_SERVICE, &MythHTTPService::Create<V2Guide> },
        { CHANNEL_SERVICE, &MythHTTPService::Create<V2Channel> },
        { STATUS_SERVICE, &MythHTTPService::Create<V2Status> },
        { CAPTURE_SERVICE, &MythHTTPService::Create<V2Capture> },
        { MUSIC_SERVICE, &MythHTTPService::Create<V2Music> },
        { CONFIG_SERVICE, &MythHTTPService::Create<V2Config> },
    };
 
    MythHTTPInstance::Addservices(be_services);
 
    // Send all unknown requests into the web app. make bookmarks and direct access work.
    auto spa_index = [](auto && PH1) { return MythHTTPRewrite::RewriteToSPA(std::forward<decltype(PH1)>(PH1), "apps/backend/index.html"); };
    MythHTTPInstance::AddErrorPageHandler({ "=404", spa_index });
 
    // Serve components of the backend web app as if they were hosted at '/'
    auto main_js = [](auto && PH1) { return MythHTTPRewrite::RewriteFile(std::forward<decltype(PH1)>(PH1), "apps/backend/main.js"); };
    auto styles_css = [](auto && PH1) { return MythHTTPRewrite::RewriteFile(std::forward<decltype(PH1)>(PH1), "apps/backend/styles.css"); };
    auto polyfills_js = [](auto && PH1) { return MythHTTPRewrite::RewriteFile(std::forward<decltype(PH1)>(PH1), "apps/backend/polyfills.js"); };
    auto runtime_js = [](auto && PH1) { return MythHTTPRewrite::RewriteFile(std::forward<decltype(PH1)>(PH1), "apps/backend/runtime.js"); };
 
    // Default index page
    auto root = [](auto && PH1) { return MythHTTPRoot::RedirectRoot(std::forward<decltype(PH1)>(PH1), "apps/backend/index.html"); };
 
    const HTTPHandlers be_handlers = {
        { "/main.js", main_js },
        { "/styles.css", styles_css },
        { "/polyfills.js", polyfills_js },
        { "/runtime.js", runtime_js },
        { "/", root }
    };
 
    MythHTTPScopedInstance webserver(be_handlers);
 
    exitCode = qApp->exec();
 
    if (gCoreContext->IsMasterBackend())
    {
        gCoreContext->SendSystemEvent("MASTER_SHUTDOWN");
        qApp->processEvents();
    }
 
    LOG(VB_GENERAL, LOG_NOTICE, "MythBackend exiting");
    be_sd_notify("STOPPING=1\nSTATUS=Exiting");
 
    return exitCode;
}
 
// This is a copy of the code from above, to start backend in a restricted mode, only running the web server
// when the database is unusable, so thet the user can use the web app to fix the settings.
 
int run_setup_webserver()
{
    LOG(VB_GENERAL, LOG_NOTICE, "***********************************************************************");
    LOG(VB_GENERAL, LOG_NOTICE, "***** MythBackend starting in Web App only mode for initial setup *****");
    LOG(VB_GENERAL, LOG_NOTICE, "***** Use http://<yourBackend>:6544 to perform setup              *****");
    LOG(VB_GENERAL, LOG_NOTICE, "***********************************************************************");
 
    const HTTPServices be_services = {
        { VIDEO_SERVICE, &MythHTTPService::Create<V2Video> },
        { MYTH_SERVICE, &MythHTTPService::Create<V2Myth> },
        { DVR_SERVICE, &MythHTTPService::Create<V2Dvr> },
        { CONTENT_SERVICE, &MythHTTPService::Create<V2Content> },
        { GUIDE_SERVICE, &MythHTTPService::Create<V2Guide> },
        { CHANNEL_SERVICE, &MythHTTPService::Create<V2Channel> },
        { STATUS_SERVICE, &MythHTTPService::Create<V2Status> },
        { CAPTURE_SERVICE, &MythHTTPService::Create<V2Capture> },
        { MUSIC_SERVICE, &MythHTTPService::Create<V2Music> },
        { CONFIG_SERVICE, &MythHTTPService::Create<V2Config> },
    };
 
    MythHTTPInstance::Addservices(be_services);
 
    // Send all unknown requests into the web app. make bookmarks and direct access work.
    auto spa_index = [](auto && PH1) { return MythHTTPRewrite::RewriteToSPA(std::forward<decltype(PH1)>(PH1), "apps/backend/index.html"); };
    MythHTTPInstance::AddErrorPageHandler({ "=404", spa_index });
 
    // Serve components of the backend web app as if they were hosted at '/'
    auto main_js = [](auto && PH1) { return MythHTTPRewrite::RewriteFile(std::forward<decltype(PH1)>(PH1), "apps/backend/main.js"); };
    auto styles_css = [](auto && PH1) { return MythHTTPRewrite::RewriteFile(std::forward<decltype(PH1)>(PH1), "apps/backend/styles.css"); };
    auto polyfills_js = [](auto && PH1) { return MythHTTPRewrite::RewriteFile(std::forward<decltype(PH1)>(PH1), "apps/backend/polyfills.js"); };
    auto runtime_js = [](auto && PH1) { return MythHTTPRewrite::RewriteFile(std::forward<decltype(PH1)>(PH1), "apps/backend/runtime.js"); };
 
    // Default index page
    auto root = [](auto && PH1) { return MythHTTPRoot::RedirectRoot(std::forward<decltype(PH1)>(PH1), "apps/backend/index.html"); };
 
    const HTTPHandlers be_handlers = {
        { "/main.js", main_js },
        { "/styles.css", styles_css },
        { "/polyfills.js", polyfills_js },
        { "/runtime.js", runtime_js },
        { "/", root }
    };
 
    MythHTTPScopedInstance webserver(be_handlers);
 
    // Provide systemd ready notification (for Type=notify)
    be_sd_notify("READY=1\nSTATUS=Started in 'Web App only mode'");
    int exitCode = qApp->exec();
 
    be_sd_notify("STOPPING=1\nSTATUS='Exiting Web App only mode'");
    LOG(VB_GENERAL, LOG_NOTICE, "MythBackend Web App only mode exiting");
    return exitCode;
}