How to copy a file in Python with a progress bar?
Overkill? Perhaps. But on almost any system, Linux, Mac, and With a quick wxWidgets install on Windows, you can have the real deal, with pause and cancel buttons in a gui setup. Macs ship with wxWidgets these days, and it's a common package on Linux.
A single file is very quick (it will immediately finish and look broken) so you might consider creating a fileSet job that ticks along once per file instead of once per block. Enjoy!
-Jim Carroll
"""
Threaded Jobs.
Any class that does a long running process can inherit
from ThreadedJob. This enables running as a background
thread, progress notification, pause and cancel. The
time remaining is also calculated by the ThreadedJob class.
"""
import wx.lib.newevent
import thread
import exceptions
import time
(RunEvent, EVT_RUN) = wx.lib.newevent.NewEvent()
(CancelEvent, EVT_CANCEL) = wx.lib.newevent.NewEvent()
(DoneEvent, EVT_DONE) = wx.lib.newevent.NewEvent()
(ProgressStartEvent, EVT_PROGRESS_START) = wx.lib.newevent.NewEvent()
(ProgressEvent, EVT_PROGRESS) = wx.lib.newevent.NewEvent()
class InterruptedException(exceptions.Exception):
def __init__(self, args = None):
self.args = args
#
#
class ThreadedJob:
def __init__(self):
# tell them ten seconds at first
self.secondsRemaining = 10.0
self.lastTick = 0
# not running yet
self.isPaused = False
self.isRunning = False
self.keepGoing = True
def Start(self):
self.keepGoing = self.isRunning = True
thread.start_new_thread(self.Run, ())
self.isPaused = False
#
def Stop(self):
self.keepGoing = False
#
def WaitUntilStopped(self):
while self.isRunning:
time.sleep(0.1)
wx.SafeYield()
#
#
def IsRunning(self):
return self.isRunning
#
def Run(self):
# this is overridden by the
# concrete ThreadedJob
print "Run was not overloaded"
self.JobFinished()
pass
#
def Pause(self):
self.isPaused = True
pass
#
def Continue(self):
self.isPaused = False
pass
#
def PossibleStoppingPoint(self):
if not self.keepGoing:
raise InterruptedException("process interrupted.")
wx.SafeYield()
# allow cancel while paused
while self.isPaused:
if not self.keepGoing:
raise InterruptedException("process interrupted.")
# don't hog the CPU
time.sleep(0.1)
#
#
def SetProgressMessageWindow(self, win):
self.win = win
#
def JobBeginning(self, totalTicks):
self.lastIterationTime = time.time()
self.totalTicks = totalTicks
if hasattr(self, "win") and self.win:
wx.PostEvent(self.win, ProgressStartEvent(total=totalTicks))
#
#
def JobProgress(self, currentTick):
dt = time.time() - self.lastIterationTime
self.lastIterationTime = time.time()
dtick = currentTick - self.lastTick
self.lastTick = currentTick
alpha = 0.92
if currentTick > 1:
self.secondsPerTick = dt * (1.0 - alpha) + (self.secondsPerTick * alpha)
else:
self.secondsPerTick = dt
#
if dtick > 0:
self.secondsPerTick /= dtick
self.secondsRemaining = self.secondsPerTick * (self.totalTicks - 1 - currentTick) + 1
if hasattr(self, "win") and self.win:
wx.PostEvent(self.win, ProgressEvent(count=currentTick))
#
#
def SecondsRemaining(self):
return self.secondsRemaining
#
def TimeRemaining(self):
if 1: #self.secondsRemaining > 3:
minutes = self.secondsRemaining // 60
seconds = int(self.secondsRemaining % 60.0)
return "%i:%02i" % (minutes, seconds)
else:
return "a few"
#
def JobFinished(self):
if hasattr(self, "win") and self.win:
wx.PostEvent(self.win, DoneEvent())
#
# flag we're done before we post the all done message
self.isRunning = False
#
#
class EggTimerJob(ThreadedJob):
""" A sample Job that demonstrates the mechanisms and features of the Threaded Job"""
def __init__(self, duration):
self.duration = duration
ThreadedJob.__init__(self)
#
def Run(self):
""" This can either be run directly for synchronous use of the job,
or started as a thread when ThreadedJob.Start() is called.
It is responsible for calling JobBeginning, JobProgress, and JobFinished.
And as often as possible, calling PossibleStoppingPoint() which will
sleep if the user pauses, and raise an exception if the user cancels.
"""
self.time0 = time.clock()
self.JobBeginning(self.duration)
try:
for count in range(0, self.duration):
time.sleep(1.0)
self.JobProgress(count)
self.PossibleStoppingPoint()
#
except InterruptedException:
# clean up if user stops the Job early
print "canceled prematurely!"
#
# always signal the end of the job
self.JobFinished()
#
#
def __str__(self):
""" The job progress dialog expects the job to describe its current state."""
response = []
if self.isPaused:
response.append("Paused Counting")
elif not self.isRunning:
response.append("Will Count the seconds")
else:
response.append("Counting")
#
return " ".join(response)
#
#
class FileCopyJob(ThreadedJob):
""" A common file copy Job. """
def __init__(self, orig_filename, copy_filename, block_size=32*1024):
self.src = orig_filename
self.dest = copy_filename
self.block_size = block_size
ThreadedJob.__init__(self)
#
def Run(self):
""" This can either be run directly for synchronous use of the job,
or started as a thread when ThreadedJob.Start() is called.
It is responsible for calling JobBeginning, JobProgress, and JobFinished.
And as often as possible, calling PossibleStoppingPoint() which will
sleep if the user pauses, and raise an exception if the user cancels.
"""
self.time0 = time.clock()
try:
source = open(self.src, 'rb')
# how many blocks?
import os
(st_mode, st_ino, st_dev, st_nlink, st_uid, st_gid, st_size, st_atime, st_mtime, st_ctime) = os.stat(self.src)
num_blocks = st_size / self.block_size
current_block = 0
self.JobBeginning(num_blocks)
dest = open(self.dest, 'wb')
while 1:
copy_buffer = source.read(self.block_size)
if copy_buffer:
dest.write(copy_buffer)
current_block += 1
self.JobProgress(current_block)
self.PossibleStoppingPoint()
else:
break
source.close()
dest.close()
except InterruptedException:
# clean up if user stops the Job early
dest.close()
# unlink / delete the file that is partially copied
os.unlink(self.dest)
print "canceled, dest deleted!"
#
# always signal the end of the job
self.JobFinished()
#
#
def __str__(self):
""" The job progress dialog expects the job to describe its current state."""
response = []
if self.isPaused:
response.append("Paused Copy")
elif not self.isRunning:
response.append("Will Copy a file")
else:
response.append("Copying")
#
return " ".join(response)
#
#
class JobProgress(wx.Dialog):
""" This dialog shows the progress of any ThreadedJob.
It can be shown Modally if the main application needs to suspend
operation, or it can be shown Modelessly for background progress
reporting.
app = wx.PySimpleApp()
job = EggTimerJob(duration = 10)
dlg = JobProgress(None, job)
job.SetProgressMessageWindow(dlg)
job.Start()
dlg.ShowModal()
"""
def __init__(self, parent, job):
self.job = job
wx.Dialog.__init__(self, parent, -1, "Progress", size=(350,200))
# vertical box sizer
sizeAll = wx.BoxSizer(wx.VERTICAL)
# Job status text
self.JobStatusText = wx.StaticText(self, -1, "Starting...")
sizeAll.Add(self.JobStatusText, 0, wx.EXPAND|wx.ALL, 8)
# wxGague
self.ProgressBar = wx.Gauge(self, -1, 10, wx.DefaultPosition, (250, 15))
sizeAll.Add(self.ProgressBar, 0, wx.EXPAND|wx.ALL, 8)
# horiz box sizer, and spacer to right-justify
sizeRemaining = wx.BoxSizer(wx.HORIZONTAL)
sizeRemaining.Add((2,2), 1, wx.EXPAND)
# time remaining read-only edit
# putting wide default text gets a reasonable initial layout.
self.remainingText = wx.StaticText(self, -1, "???:??")
sizeRemaining.Add(self.remainingText, 0, wx.LEFT|wx.RIGHT|wx.ALIGN_CENTER_VERTICAL, 8)
# static text: remaining
self.remainingLabel = wx.StaticText(self, -1, "remaining")
sizeRemaining.Add(self.remainingLabel, 0, wx.ALL|wx.ALIGN_CENTER_VERTICAL, 8)
# add that row to the mix
sizeAll.Add(sizeRemaining, 1, wx.EXPAND)
# horiz box sizer & spacer
sizeButtons = wx.BoxSizer(wx.HORIZONTAL)
sizeButtons.Add((2,2), 1, wx.EXPAND|wx.ADJUST_MINSIZE)
# Pause Button
self.PauseButton = wx.Button(self, -1, "Pause")
sizeButtons.Add(self.PauseButton, 0, wx.ALL, 4)
self.Bind(wx.EVT_BUTTON, self.OnPauseButton, self.PauseButton)
# Cancel button
self.CancelButton = wx.Button(self, wx.ID_CANCEL, "Cancel")
sizeButtons.Add(self.CancelButton, 0, wx.ALL, 4)
self.Bind(wx.EVT_BUTTON, self.OnCancel, self.CancelButton)
# Add all the buttons on the bottom row to the dialog
sizeAll.Add(sizeButtons, 0, wx.EXPAND|wx.ALL, 4)
self.SetSizer(sizeAll)
#sizeAll.Fit(self)
sizeAll.SetSizeHints(self)
# jobs tell us how they are doing
self.Bind(EVT_PROGRESS_START, self.OnProgressStart)
self.Bind(EVT_PROGRESS, self.OnProgress)
self.Bind(EVT_DONE, self.OnDone)
self.Layout()
#
def OnPauseButton(self, event):
if self.job.isPaused:
self.job.Continue()
self.PauseButton.SetLabel("Pause")
self.Layout()
else:
self.job.Pause()
self.PauseButton.SetLabel("Resume")
self.Layout()
#
#
def OnCancel(self, event):
self.job.Stop()
#
def OnProgressStart(self, event):
self.ProgressBar.SetRange(event.total)
self.statusUpdateTime = time.clock()
#
def OnProgress(self, event):
# update the progress bar
self.ProgressBar.SetValue(event.count)
self.remainingText.SetLabel(self.job.TimeRemaining())
# update the text a max of 20 times a second
if time.clock() - self.statusUpdateTime > 0.05:
self.JobStatusText.SetLabel(str(self.job))
self.statusUpdateTime = time.clock()
self.Layout()
#
#
# when a job is done
def OnDone(self, event):
self.ProgressBar.SetValue(0)
self.JobStatusText.SetLabel("Finished")
self.Destroy()
#
#
if __name__ == "__main__":
app = wx.PySimpleApp()
#job = EggTimerJob(duration = 10)
job = FileCopyJob("VeryBigFile.mp4", "/tmp/test_junk.mp4", 1024*1024*10)
dlg = JobProgress(None, job)
job.SetProgressMessageWindow(dlg)
job.Start()
dlg.ShowModal()
#
Two things:
- I would make the default block size a lot larger than 512. I would start with 16384 and perhaps more.
- For modularity, it might be better to have the
copy_with_progfunction not output the progress bar itself, but call a callback function so the caller can decide how to display the progress.
Perhaps something like this:
def copy_with_prog(src, dest, callback = None):
while True:
# copy loop stuff
if callback:
callback(pos, total)
prog = ProgressBar(...)
copy_with_prog(src, dest, lambda pos, total: prog.update(pos, total))