如何使用进度条在Python中复制文件？

使用时复制大文件时shutil.copy(),不会指示操作是如何进行的.

我把一些有用的东西放在一起 - 它使用一个简单的ProgressBar类(简单的返回一个简单的ASCII进度条,作为一个字符串),以及一个循环open().read()和.write()进行实际的复制.它显示使用的进度条sys.stdout.write("\r%s\r" % (the_progress_bar))有点hackish,但它的工作原理.

你可以在这里看到github上的代码(在上下文中)

是否有更好的内置模块？是否可以对此代码进行任何改进？

两件事情:

我想使默认的块大小,很多比512大,我将开始与16384,也许更.

对于模块化,最好让copy_with_prog函数不输出进度条本身,但调用回调函数以便调用者可以决定如何显示进度.

也许是这样的:

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))

矫枉过正？也许.但是在几乎任何系统上,Linux,Mac和Windows上都安装了一个快速的wxWidgets,你可以通过gui设置中的暂停和取消按钮进行真正的交易.Macs最近附带了wxWidgets,它是Linux上常见的软件包.

单个文件非常快(它会立即完成并且看起来很糟糕),因此您可以考虑创建一个fileSet作业,每个文件一次,而不是每个块一次.请享用!

- 吉姆卡罗尔

"""
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()
#