Simple torrent client with PyQt

Question

Recently I have started my Python practice. It's very useful PL, especially when you're using Linux. So here's my problem: I really like simplicity of Qt and power of Python but it has overgrown me a little bit. I want to build a very simple torrent client using PyQt and libtorrent. I've even got a ready to use code of that for downloading one torrent at the time. Although, I'm having trouble with integrating the app code with Qt's code. Here's the code of torrent.py: #!/usr/bin/python import sys from PyQt4 import QtCore, QtGui import libtorrent as lt import time

from torrent_ui import Ui_Form, ses


class MyForm(QtGui.QMainWindow):
    def __init__(self, parent=None):
        QtGui.QWidget.__init__(self, parent)
        self.ui = Ui_Form()
        self.ui.setupUi(self)


if __name__ == "__main__":
    app = QtGui.QApplication(sys.argv)
    myapp = MyForm()
    myapp.show()


    ses.listen_on(6881, 6891)
    #e = lt.bdecode(open("test.torrent", 'rb').read())
    info = lt.torrent_info("g.torrent")
    h = ses.add_torrent({'ti': info, 'save_path': './'})
    print 'starting', h.name()

    while (not h.is_seed()):
       s = h.status()

       state_str = ['queued', 'checking', 'downloading metadata', 'downloading', 'finished', 'seeding', 'allocating', 'checking fastresume']
       print '\r%.2f%% complete (down: %.1f kb/s up: %.1f kB/s peers: %d) %s' % (s.progress * 100, s.download_rate / 1000, s.upload_rate / 1000, s.num_peers, state_str[s.state]),
       sys.stdout.flush()
       #ses.pause()

       time.sleep(1)

    print h.name(), 'complete'
    sys.exit(app.exec_())

The code generated from PyQt:

#!/usr/bin/python
# -*- coding: utf-8 -*-

# Form implementation generated from reading ui file 'untitled.ui'
#
# Created: Mon Apr 29 21:13:06 2013
#      by: PyQt4 UI code generator 4.10
#
# WARNING! All changes made in this file will be lost!

from PyQt4 import QtCore, QtGui
import sys
import libtorrent as lt
ses = lt.session()
try:
    _fromUtf8 = QtCore.QString.fromUtf8
except AttributeError:
    def _fromUtf8(s):
        return s

try:
    _encoding = QtGui.QApplication.UnicodeUTF8
    def _translate(context, text, disambig):
        return QtGui.QApplication.translate(context, text, disambig, _encoding)
except AttributeError:
    def _translate(context, text, disambig):
        return QtGui.QApplication.translate(context, text, disambig)

class Ui_Form(object):
    def setupUi(self, Form):
        Form.setObjectName(_fromUtf8("Form"))
        Form.resize(640, 480)
        self.closeb = QtGui.QPushButton(Form)
        self.closeb.setGeometry(QtCore.QRect(520, 440, 98, 27))
        self.closeb.setObjectName(_fromUtf8("closeb"))
        self.listView = QtGui.QListView(Form)
        self.listView.setGeometry(QtCore.QRect(30, 20, 581, 261))
        self.listView.setObjectName(_fromUtf8("listView"))
        self.newtorb = QtGui.QPushButton(Form)
        self.newtorb.setGeometry(QtCore.QRect(30, 300, 98, 27))
        self.newtorb.setObjectName(_fromUtf8("newtorb"))
        self.stopb = QtGui.QPushButton(Form)
        self.stopb.setGeometry(QtCore.QRect(130, 300, 98, 27))
        self.stopb.setObjectName(_fromUtf8("stopb"))
        self.pauseb = QtGui.QPushButton(Form)
        self.pauseb.setGeometry(QtCore.QRect(230, 300, 98, 27))
        self.pauseb.setObjectName(_fromUtf8("pauseb"))
        self.selectallb = QtGui.QPushButton(Form)
        self.selectallb.setGeometry(QtCore.QRect(330, 300, 141, 27))
        self.selectallb.setObjectName(_fromUtf8("selectallb"))
        #self.ses = lt.session()
        self.retranslateUi(Form)
        QtCore.QObject.connect(self.closeb, QtCore.SIGNAL(_fromUtf8("clicked()")), Form.close)
        QtCore.QObject.connect(self.pauseb, QtCore.SIGNAL(_fromUtf8("clicked()")), self.pausef)
        QtCore.QObject.connect(self.stopb, QtCore.SIGNAL(_fromUtf8("clicked()")), self.stopb.click)
        QtCore.QObject.connect(self.newtorb, QtCore.SIGNAL(_fromUtf8("clicked()")), self.newtorb.click)
        QtCore.QObject.connect(self.selectallb, QtCore.SIGNAL(_fromUtf8("clicked()")), self.listView.selectAll)
        QtCore.QMetaObject.connectSlotsByName(Form)

    def retranslateUi(self, Form):
        Form.setWindowTitle(_translate("Form", "JKTorrent", None))
        self.closeb.setText(_translate("Form", "close", None))
        self.newtorb.setText(_translate("Form", "Dodaj newtor", None))
        self.stopb.setText(_translate("Form", "stop", None))
        self.pauseb.setText(_translate("Form", "pause", None))
        self.selectallb.setText(_translate("Form", "Zaznacz wszystkie", None))
    def pausef(self):
        self.ses.pause()

The main problem is, that when the torrent downloading works, the Qt app window does not show up. The other problem's I don't know how to put the libtorrent code into that fancy Qt window (to print all of the data into a list view). Please, help me with that.

Answer 1

Your problem is that you have some code before the app.exec_(). The window shows when that is executed. The part

ses.listen_on(6881, 6891)
#e = lt.bdecode(open("test.torrent", 'rb').read())
info = lt.torrent_info("g.torrent")
h = ses.add_torrent({'ti': info, 'save_path': './'})
print 'starting', h.name()

while (not h.is_seed()):
   s = h.status()

   state_str = ['queued', 'checking', 'downloading metadata', 'downloading', 'finished', 'seeding', 'allocating', 'checking fastresume']
   print '\r%.2f%% complete (down: %.1f kb/s up: %.1f kB/s peers: %d) %s' % (s.progress * 100, s.download_rate / 1000, s.upload_rate / 1000, s.num_peers, state_str[s.state]),
   sys.stdout.flush()
   #ses.pause()

   time.sleep(1)

should be removed from the main function and should be running, maybe in a separate thread, in a function that is started in the __init__ of MyForm.

It's a bit unclear what your problems with QListView are. I recommend that you use a QTreeWidget instead, I found the documentation to be quite helpful.