File pgadmin4-desktop of Package pgadmin4

#!/usr/bin/python3
#
# This is a small script that tries to replace pgadmin4-runtime as
# a desktop version of pgadmin4.

# pgadmin4-runtime uses NW.js (which is based on Chromium and Node.js) which
# makes it hard to package in a standard way.
# pgadmin4-desktop tries to be a simple replacement which just runs pgadmin4
# in runtime mode but uses Qt6 for the GUI in order to show an icon in the
# system tray and provide two options: open a new browser window with pgAdmin
# and quit the application.
#
# This script is released under the PostgreSQL License.
# (C) 2023 Antonio Larrosa <alarrosa@suse.com>

import subprocess
import os
import os.path
import uuid
import socket
import time
import sys
import fcntl
from PyQt5.QtWidgets import QApplication, QSystemTrayIcon, QMenu, QSplashScreen, QAction
from PyQt5.QtGui import QIcon, QPixmap, QImage, QPalette, QPainter
from PyQt5.QtCore import QTimer, Qt


class PGAdminDesktop(QApplication):
    def __init__(self):
        super().__init__(sys.argv)
        self.environ = os.environ
        self.pgadmin_process = None
        self.url = None

        self.setQuitOnLastWindowClosed(False)
        self.aboutToQuit.connect(self.cleanup)
        self.create_ui()

        pixmap = self.load_splash_pixmap()
        if pixmap:
            self.splash = QSplashScreen(pixmap)
            self.splash.showMessage("Starting pgAdmin.", Qt.AlignmentFlag.AlignBottom)
            self.splash.show()
        else:
            self.splash = None

        self.run_pgadmin_server()
        QTimer.singleShot(500, self.open_pgadmin)

    def load_splash_pixmap(self):
        paths = [path + '/pgadmin4/assets/welcome_logo.svg' for path in sys.path]
        paths = [path for path in paths if os.path.exists(path)]
        if not paths:
            return None
        return QPixmap(paths[0])

    def run_pgadmin_server(self):
        if 'PGADMIN_INT_KEY' not in self.environ:
            self.environ['PGADMIN_INT_KEY'] = str(uuid.uuid4())

        if 'PGADMIN_INT_PORT' not in self.environ:
            self.environ['PGADMIN_INT_PORT'] = '5051'
 
        self.environ['PGADMIN_SERVER_MODE'] = 'OFF'
        self.pgadmin_process = subprocess.Popen(['pgadmin4'],
                                                env=self.environ, shell=True)

    def create_ui(self):
        icon = QIcon.fromTheme("pgadmin4")
        self.tray = QSystemTrayIcon()
        self.tray.setIcon(icon)
        self.tray.setVisible(True)

        menu = QMenu()

        self.title = QAction("pgAdmin")
        self.title.setEnabled(False)
        menu.addAction(self.title)
        menu.addSeparator()

        self.openPGAdminAction = QAction("New Window")
        menu.addAction(self.openPGAdminAction)
        self.openPGAdminAction.triggered.connect(self.open_pgadmin)

        self.quitAction = QAction("Quit")
        menu.addAction(self.quitAction)
        self.quitAction.triggered.connect(self.quit)

        self.tray.setContextMenu(menu)

    def check_if_pgadmin_is_running(self):
        sock = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
        sock.settimeout(1)
        result = sock.connect_ex(('127.0.0.1',
                                  int(self.environ['PGADMIN_INT_PORT'])))

        if result == 0:
            if self.splash:
                self.splash.hide()
            port = self.environ['PGADMIN_INT_PORT']
            key = self.environ['PGADMIN_INT_KEY']
            subprocess.run(["xdg-open", f"http://127.0.0.1:{port}/?key={key}"])

            self.openPGAdminAction.setText("New Window")
            self.openPGAdminAction.setEnabled(True)
        else:
            self.checks_for_pgadmin += 1
            if self.checks_for_pgadmin < 15:
                dots = "." * (self.checks_for_pgadmin % 3 + 1)
                self.openPGAdminAction.setText("Opening pgAdmin" + dots)
                if self.splash and not self.splash.isHidden():
                    self.splash.showMessage("Starting pgAdmin" + dots, Qt.AlignmentFlag.AlignBottom)
                    
                QTimer.singleShot(1000, self.check_if_pgadmin_is_running)
            else:
                error_msg = 'Timeout waiting for pgAdmin to start. Exiting...' 
                print(error_msg)
                self.splash.showMessage(error_msg, Qt.AlignmentFlag.AlignBottom)
                QTimer.singleShot(10000, self.quit)


    def open_pgadmin(self):
        self.openPGAdminAction.setText("Opening pgAdmin...")
        self.openPGAdminAction.setEnabled(False)
        self.checks_for_pgadmin = 0
        QTimer.singleShot(1000, self.check_if_pgadmin_is_running)

    def cleanup(self):
        self.pgadmin_process.kill()


if __name__ == '__main__':
    app = PGAdminDesktop()
    sys.exit(app.exec())