thehub/support/docker/rest-service0.2/startRestv02/main.cpp

/*
 * This file is part of the Flowee project
 * Copyright (C) 2019-2020 Tom Zander <tom@flowee.org>
 *
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * This program 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 General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */
#include <QCoreApplication>
#include <QDir>
#include <QTextStream>
#include <QProcess>
#include <qdebug.h>

#include <unistd.h>
#include <signal.h>
#include <ifaddrs.h>
#ifndef _GNU_SOURCE
# define _GNU_SOURCE     /* To get defns of NI_MAXHOST */
#endif
#include <netdb.h>

/*
   Interprets env vars;
    FLOWEE_HUB=host:port
    FLOWEE_INDEXER=host:port

    FLOWEE_HUBS=host:port
    FLOWEE_INDEXERS=host:port

    FLOWEE_JSON_VERBOSE=x
 */

static QProcess *proc = new QProcess();

QStringList hubs()
{
    QStringList answer;
    const char *flowee_hub = getenv("FLOWEE_HUB");
    const char *flowee_hubs = getenv("FLOWEE_HUBS");
    if (flowee_hub)
        answer.append(QString::fromLocal8Bit(flowee_hub));
    if (flowee_hubs) {
        for (auto h : QString::fromLocal8Bit(flowee_hubs).split(QRegExp("[ ,;&]"), QString::SkipEmptyParts)) {
            answer.append(h);
        }
    }
    if (answer.isEmpty()) {
        qWarning() << "No info passed where to find the Hub, trying localhost";
        qWarning() << "Suggest to pass FLOWEE_HUB with 'IP' or 'IP:port' where a running Hub can be found";
        answer.append("localhost");
    }
    return answer;
}

QStringList indexers()
{
    QStringList answer;
    const char *flowee_indexer = getenv("FLOWEE_INDEXER");
    const char *flowee_indexers = getenv("FLOWEE_INDEXERS");
    if (flowee_indexer)
        answer.append(QString::fromLocal8Bit(flowee_indexer));
    if (flowee_indexers) {
        for (auto h : QString::fromLocal8Bit(flowee_indexers).split(QRegExp("[ ,;&]"), QString::SkipEmptyParts)) {
            answer.append(h);
        }
    }
    if (answer.isEmpty()) {
        qWarning() << "No info passed where to find the indexer, trying localhost";
        qWarning() << "Suggest to pass FLOWEE_INDEXER with 'IP' or 'IP:port' where a running indexer can be found";
        answer.append("localhost");
    }
    return answer;
}

void HandleSignals(int) {
qWarning() << "Docker: TERM received";
    qint64 pid = proc->processId();
    if (pid > 0) kill(pid, SIGTERM); // politely tell the proc to terminate
}

int main(int x, char**y) {
    QCoreApplication app(x,y);

    const QDir confDir(QDir::homePath() + "/.config/flowee/bitcore-proxy");
    confDir.mkpath(".");

    QFile configFile(confDir.absolutePath() + "/bitcore-proxy.conf");
    if (!configFile.open(QIODevice::WriteOnly)) {
        qWarning() << "Can't write conf file";
    } else {
        QTextStream out(&configFile);
        out << "# autogenerated flowee bitcore-proxy config\n\n[services]\n";

        for (auto h : hubs()) {
            out << "hub=" << h << endl;
        }
        for (auto i : indexers()) {
            out << "indexer=" << i << endl;
        }
        if (getenv("FLOWEE_JSON_VERBOSE"))
            out << "\n[json]\ncompact=false\n";

        configFile.close();
    }

    QFile logsFile(confDir.absolutePath() + "/logs.conf");
    if (logsFile.exists()) {
        qWarning() << "Not changing existing logs.conf";
    }
    else if (!logsFile.open(QIODevice::WriteOnly)) {
        qWarning() << "Can't write logs.conf file" << confDir.absoluteFilePath("logs.conf");
    }
    else {
        QTextStream out(&logsFile);
        out << "# Flowee logging config.\n"
               "channel console\n"
               "  option timestamp\n";
        QString logLevel = getenv("FLOWEE_LOGLEVEL");
        if (logLevel.toLower() == "info")
            out << "\nALL info\n";
        else if (logLevel.toLower() == "quiet")
            out << "\nALL quiet\n";
        else if (logLevel.toLower() == "silent")
            out << "\nALL silent\n";
        else if (!logLevel.isEmpty())
            qWarning() << "FLOWEE_LOGLEVEL not understood. Options are 'info', 'quiet' or 'silent'";
        logsFile.close();
    }

    struct sigaction sa;
    sa.sa_handler = HandleSignals;
    sigemptyset(&sa.sa_mask);
    sa.sa_flags = 0;
    sigaction(SIGTERM, &sa, NULL);
    sigaction(SIGINT, &sa, NULL);

    // Ignore SIGPIPE
    signal(SIGPIPE, SIG_IGN);

    QStringList args;
    args << "--conf" << confDir.absolutePath() + "/bitcore-proxy.conf";

    // the http server can only listen on one interface and defaults to localhost.
    // We should listen on the public interface instead in order to make standard (bridge) docker
    // networking work and allow port forwarding which won't work when binding on localhost.

    struct ifaddrs *ifaddr;
    if (getifaddrs(&ifaddr) != -1) {
        for (struct ifaddrs *ifa = ifaddr; ifa; ifa = ifa->ifa_next) {
            if (ifa->ifa_addr == nullptr)
                continue;
            int family = ifa->ifa_addr->sa_family;
            if (family != AF_INET || ifa->ifa_addr->sa_data[2] == 127)
                continue;
            char host[NI_MAXHOST];
            if (getnameinfo(ifa->ifa_addr, sizeof(struct sockaddr_in), host, NI_MAXHOST, nullptr, 0, NI_NUMERICHOST) == 0) {
                args << QString("--bind") << QString(host);
                break;
            }
            freeifaddrs(ifaddr);
        }
    }

    proc->setReadChannel(QProcess::StandardOutput);
    proc->start(QLatin1String("/usr/bin/rest-service"), args, QIODevice::ReadOnly);
    proc->waitForReadyRead(20000);
    if (proc->state() == QProcess::NotRunning) { // time out
        qWarning() << "ERROR: rest-service(v2) fails to start, timing out";
        proc->kill();
        return 1;
    }
    QTextStream out(stdout);
    while (true) {
        auto logData = proc->readAllStandardError();
        out << logData;
        logData = proc->readAllStandardOutput();
        out << logData;
        if (proc->state() != QProcess::Running)
            break;
        out.flush();
        proc->waitForReadyRead(20000);
    }

    fflush(NULL);
    sync();

    return proc->exitCode();
}