Parcali dosya cekimi / Downloading files in chunks.

download.py

class  Durum:
    def __init__(self, app = QtGui.QApplication, widget=None):
        self.app = app
        self.widget = widget

    def guncelle(self, mesaj):
        if type(self.widget) is QtGui.QListWidget:
            self.widget.addItem(mesaj)
        if type(self.widget) is QtGui.QLabel:
            self.widget.setText(mesaj)
        if type(self.widget) is QtGui.QLineEdit:
            self.widget.setText(mesaj)
        self.app.processEvents()
        
        
def download_file(url, fname, csize=5000000, durum=None):    
    basla = datetime.now()
    # NOTE the stream=True parameter
    start = None
    if os.path.isfile(fname) is True:
        start = os.stat(fname).st_size - 1
    else:
        start = 0
        f = open(fname,"wb")
        f.close()
    cekilen = 0
    r = requests.get(url, stream=True, verify=False )
    finish = int(r.headers['content-length'])
    boy = finish
    for st in range(start, finish, csize):
        if st + csize < finish:
            end = st + csize
        else:
            end = finish

        q = None
        status = False
        while status is False:
            try:
                if st == 0:
                    st = -1
                q = requests.get(url, verify=False, headers = { "range" : "bytes=%d-%d" % (st +1, end)})
                status = (q.status_code == 206)
            except:
                status = False
                if durum is not None:
                    durum.guncelle("Dosya cekmede problem.. Yeniden deniyoruz")
                time.sleep(10)
        cekilen += csize
        f = open(fname, "a+b")
        f.write(q.content)
        f.close()

        zaman = datetime.now()
        sure = (zaman - basla).total_seconds()
        if sure > 0:
            hiz = cekilen / sure
            kalan_sure = (finish - st) / hiz
            sa = 0
            dk = kalan_sure / 60
            sn = kalan_sure % 60
            if dk > 60:
                sa = dk / 60
                dk = dk % 60
            kln = "%02d:%02d:%02d" % (sa, dk, sn)
            if durum is not None:
                durum.guncelle("%.2f MB  dosyanin %.2f MB'i cekildi, hiz %.2f MB/sn , kalan sure  %s"
                               % (boy / 1048576.0, cekilen / 1048576.0, hiz / 1048576.0, kln))
    if durum is not None:
        durum.guncelle("Yedek geri alma islemi bitti")
    return fname