How To Update Progress Bar As Well As Download File Using Multi-threading

I'm trying to download files using the Request module using Multi threading and simultaneously need to Update a Progress bar as well. But while doing so, whenever I press submit bu

Solution 1:

With apologies to Mike for highjacking his code for a skeleton, here is a rough version using urlretrieve and a wxPython event to do the updating.

import os
import wx
import time
from threading import Thread
from urllib.request import FancyURLopener
from urllib.request import urlopen
import wx.lib.newevent

urlretrieve = FancyURLopener().retrieve
progress_event, EVT_PROGRESS_EVENT = wx.lib.newevent.NewEvent()

classDownloadThread(Thread):

    def__init__(self, parent, url, fsize):
        """Constructor"""
        Thread.__init__(self)
        self.fsize = fsize
        self.url = url
        self.parent = parent
        self.start()

    defrun(self):
        local_fname = os.path.basename(self.url)
        urlretrieve(self.url, local_fname, self.reporthook)

    defreporthook(self,blocknum, blocksize, totalsize):
        readsofar = blocknum * blocksize
        if totalsize > 0:
            percent = int((readsofar / totalsize) * 100)
        else: # total size is unknown
            percent = 0
        evt = progress_event(count=percent)
        #Send back current count for the progress bartry:
            wx.PostEvent(self.parent, evt)
        except: # The parent frame has probably been destroyedpassclassMyPanel(wx.Panel):
    def__init__(self, parent):
        """Constructor"""
        wx.Panel.__init__(self, parent)

        self.lbl = wx.StaticText(self, label="Download URL:")
        self.dl_txt = wx.TextCtrl(self)
        btn = wx.Button(self, label="Download")
        self.gauge = wx.Gauge(self, -1, range=100)

        self.main_sizer = wx.BoxSizer(wx.VERTICAL)
        dl_sizer = wx.BoxSizer(wx.HORIZONTAL)

        dl_sizer.Add(self.dl_txt, 1, wx.EXPAND|wx.ALL, 5)
        dl_sizer.Add(btn, 0, wx.ALL, 5)

        self.main_sizer.Add(dl_sizer, 0, wx.EXPAND)
        self.main_sizer.Add(self.lbl, 0, wx.ALL|wx.CENTER, 5)
        self.main_sizer.Add(self.gauge, 0, wx.ALL|wx.EXPAND, 5)

        self.SetSizer(self.main_sizer)

        #Bind to the progress event issued by the thread
        self.Bind(EVT_PROGRESS_EVENT, self.OnProgress)
        btn.Bind(wx.EVT_BUTTON, self.OnDownload)

    defOnDownload(self, event):
        url = self.dl_txt.GetValue()
        self.lbl.SetLabel(os.path.basename(url))
        try:
            header = urlopen(url)
            fsize = int(header.headers['Content-Length'])
            # start thread
            d_thread = DownloadThread(self, url, fsize)
            while d_thread.isAlive():
                time.sleep(0.1)
                wx.GetApp().Yield()
                continue# Finished re-set
            self.dl_txt.SetValue("")
            self.lbl.SetLabel("Download URL:")
            self.gauge.SetValue(0)

        except Exception as e:
            print ("Error: ", e)

    defOnProgress(self, event):
        """"""
        self.gauge.SetValue(event.count)

classDownloaderFrame(wx.Frame):

    def__init__(self):
        """Constructor"""
        wx.Frame.__init__(self, None, title="Downloader", size=(800, 400))
        panel = MyPanel(self)
        self.Show()

if __name__ == "__main__":
    app = wx.App(False)
    frame = DownloaderFrame()
    app.MainLoop()

Solution 2:

I wrote a tutorial on this topic a while back.

Here's the code:

import requests
import os
import wx
import wx.lib.scrolledpanel as scrolled

from threading import Thread
from wx.lib.pubsub import pub


classDownloadThread(Thread):
    """Downloading thread"""def__init__(self, gnum, url, fsize):
        """Constructor"""
        Thread.__init__(self)
        self.fsize = fsize
        self.gnum = gnum
        self.url = url
        self.start()

    defrun(self):
        """
        Run the worker thread
        """
        local_fname = os.path.basename(self.url)
        count = 1whileTrue:
            if os.path.exists(local_fname):
                tmp, ext = os.path.splitext(local_fname)
                cnt = "(%s)" % count
                local_fname = tmp + cnt + ext
                count += 1else:
                break
        req = requests.get(self.url, stream=True)
        total_size = 0print(local_fname)
        withopen(local_fname, "wb") as fh:
            for byte in req.iter_content(chunk_size=1024):
                if byte:
                    fh.write(byte)
                    fh.flush()
                total_size += len(byte)
                if total_size < self.fsize:
                    wx.CallAfter(pub.sendMessage,
                                 "update_%s" % self.gnum,
                                 msg=total_size)
        wx.CallAfter(pub.sendMessage,
                     "update_%s" % self.gnum,
                     msg=self.fsize)



classMyGauge(wx.Gauge):
    """"""def__init__(self, parent, range, num):
        """Constructor"""
        wx.Gauge.__init__(self, parent, range=range)

        pub.subscribe(self.updateProgress, "update_%s" % num)


    defupdateProgress(self, msg):
        """"""
        self.SetValue(msg)


classMyPanel(scrolled.ScrolledPanel):
    """"""def__init__(self, parent):
        """Constructor"""
        scrolled.ScrolledPanel.__init__(self, parent)

        self.data = []
        self.download_number = 1# create the sizers
        self.main_sizer = wx.BoxSizer(wx.VERTICAL)
        dl_sizer = wx.BoxSizer(wx.HORIZONTAL)

        # create the widgets
        lbl = wx.StaticText(self, label="Download URL:")
        self.dl_txt = wx.TextCtrl(self)
        btn = wx.Button(self, label="Download")
        btn.Bind(wx.EVT_BUTTON, self.onDownload)

        # layout the widgets
        dl_sizer.Add(lbl, 0, wx.ALL|wx.CENTER, 5)
        dl_sizer.Add(self.dl_txt, 1, wx.EXPAND|wx.ALL, 5)
        dl_sizer.Add(btn, 0, wx.ALL, 5)
        self.main_sizer.Add(dl_sizer, 0, wx.EXPAND)

        self.SetSizer(self.main_sizer)
        self.SetAutoLayout(1)
        self.SetupScrolling()

    defonDownload(self, event):
        """
        Update display with downloading gauges
        """
        url = self.dl_txt.GetValue()
        try:
            header = requests.head(url)
            fsize = int(header.headers["content-length"]) / 1024

            sizer = wx.BoxSizer(wx.HORIZONTAL)
            fname = os.path.basename(url)
            lbl = wx.StaticText(self, label="Downloading %s" % fname)
            gauge = MyGauge(self, fsize, self.download_number)

            sizer.Add(lbl, 0, wx.ALL|wx.CENTER, 5)
            sizer.Add(gauge, 0, wx.ALL|wx.EXPAND, 5)
            self.main_sizer.Add(sizer, 0, wx.EXPAND)

            self.Layout()

            # start thread
            DownloadThread(self.download_number, url, fsize)
            self.dl_txt.SetValue("")
            self.download_number += 1except Exception as e:
            print("Error: ", e)

classDownloaderFrame(wx.Frame):
    """"""def__init__(self):
        """Constructor"""
        wx.Frame.__init__(self, None, title="Downloader", size=(800, 400))
        panel = MyPanel(self)
        self.Show()

if __name__ == "__main__":
    app = wx.App(False)
    frame = DownloaderFrame()
    app.MainLoop()