mergin_gui2.py

import os

from PyQt5.QtCore import QTimer
from PyQt5.QtWidgets import QWidget, QVBoxLayout, QProgressBar, QApplication, QPushButton, QLabel, QMessageBox

from mergin import (
    MerginClient,
    MerginProject,
    InvalidProject,
    ClientError,
)

from mergin.client_pull import download_project_async, download_project_is_running, download_project_finalize, download_project_cancel

# config
project = "martin/fibre"
mergin_user = "martin"
mergin_pass = "xxx"
c = MerginClient("https://public.cloudmergin.com/", None, mergin_user, mergin_pass)
directory = os.path.basename(project)


app = QApplication([])

class MyWidget(QWidget):
    def __init__(self, parent=None):
        QWidget.__init__(self, parent)
        
        self.bar = QProgressBar(self)
        self.status_label = QLabel(self)
        self.start_button = QPushButton(self)
        self.start_button.setText("Start!")
        self.cancel_button = QPushButton(self)
        self.cancel_button.setText("Cancel!")
        
        main_layout = QVBoxLayout()
        main_layout.addWidget(self.bar)
        main_layout.addWidget(self.status_label)
        main_layout.addWidget(self.start_button)
        main_layout.addWidget(self.cancel_button)
        self.setLayout(main_layout)
        
        self.timer = QTimer(self)
        self.timer.setInterval(100)
        
        self.start_button.clicked.connect(self.start_download)
        self.cancel_button.clicked.connect(self.cancel_download)
        self.timer.timeout.connect(self.timer_timeout)
        
        self.job = None

    def start_download(self):
        if self.job:
            QMessageBox.information(self, "msg", "already downloading")
            return
        try:
            self.job = download_project_async(c, project, directory)
        except ClientError as e:
            QMessageBox.critical(self, "msg", "Client error: " + str(e))
            return

        self.status_label.setText("downloading!")
        self.bar.setMaximum(self.job.total_size)
        self.bar.setValue(0)
        self.timer.start()
        
    def timer_timeout(self):
        self.bar.setValue(self.job.transferred_size)
        
        try:
            is_running = download_project_is_running(self.job)
        except ClientError as e:
            # also try to cancel the job so that we do not need to wait for other workers
            self.cancel_download()
            self.status_label.setText("error!")
            QMessageBox.critical(self, "msg", "Client error: " + str(e))
            return

        if not is_running:
            self.timer.stop()
            try:
                # this should not raise an exception anymore because we were signalled that
                # all workers have finished successfully. But maybe something in finalization could fail (e.g. disk full?)
                download_project_finalize(self.job)
            except ClientError as e:
                self.job = None
                self.status_label.setText("error!")
                QMessageBox.critical(self, "msg", "Client error: " + str(e))
                return

            self.job = None
            self.status_label.setText("")
            QMessageBox.information(self, "msg", "DONE!")
        
    def cancel_download(self):
        if not self.job:
            QMessageBox.information(self, "msg", "download not active")
            return
        self.timer.stop()
        self.status_label.setText("cancelled!")
        download_project_cancel(self.job)
        self.job = None


w = MyWidget()
w.show()
app.exec_()