Ticket #4242: test_copying_file.py

import tempfile
import epdb
import StringIO

from gi.repository import GObject
from gi.repository import Gio
from gi.repository import GLib



# Avoid "Fatal Python error: GC object already tracked"
# http://stackoverflow.com/questions/7496629/gstreamer-appsrc-causes-random-crashes
GObject.threads_init()


class FileTransfer(GObject.GObject):
    _CHUNK_SIZE = 10240

    def __init__(self, input_stream, output_stream):
        GObject.GObject.__init__(self)

        self._input_stream = input_stream
        self._output_stream = output_stream
        self._pending_buffers = StringIO.StringIO()
        self._buffer = []

    def start(self):
        self._input_stream.read_async(
            self._pending_buffers, self._CHUNK_SIZE, GLib.PRIORITY_LOW,
            None, self.__read_async_cb, 'user_data arg')

    def __read_async_cb(self, input_stream, result, user_data):
        print input_stream
        print result
        data = input_stream.read_finish(result)
        print data

        if not data:
            self._input_stream.close(None)
        else:
            # self._pending_buffers.append(data)
            self._input_stream.read_async(
                self._buffer, self._CHUNK_SIZE, GLib.PRIORITY_LOW,
                None, self.__read_async_cb, 'user_data_arg2')
        self._write_next_buffer()

    def __write_async_cb(self, output_stream, result, user_data):
        print user_data

        if not self._pending_buffers and \
                not self._output_stream.has_pending() and \
                not self._input_stream.has_pending():
            output_stream.close(None)
        else:
            self._write_next_buffer()

    def _write_next_buffer(self):
        print self._output_stream


        if not self._output_stream.has_pending():
            # data = self._pending_buffers.pop(0)
            # TODO: we pass the buffer as user_data because of
            # http://bugzilla.gnome.org/show_bug.cgi?id=564102
            self._output_stream.write_async(
                self._pending_buffers, self._CHUNK_SIZE, GLib.PRIORITY_LOW, None,
                self.__write_async_cb)


test_file_name = '/home/humitos/test.py'
test_input_stream = Gio.File.new_for_path(test_file_name).read(None)
test_output_stream = Gio.File.new_for_path(
    tempfile.mkstemp()[1]).append_to(Gio.FileCreateFlags.PRIVATE, None)

splicer = FileTransfer(test_input_stream, test_output_stream)
splicer.start()

loop = GObject.MainLoop()
loop.run()