我使用以下Python脚本通过FTP下载文件.我想要的是在下载时查看进度的详细信息.为此,我使用了ProgressBar但它没有显示任何内容.

这是我的代码：

import re

import os

import ftplib

import ntpath

import sys

import time

from progressbar import AnimatedMarker, Bar, BouncingBar, Counter, ETA, \

AdaptiveETA, FileTransferSpeed, FormatLabel, Percentage, \

ProgressBar, ReverseBar, RotatingMarker, \

SimpleProgress, Timer, UnknownLength

ftp = ftplib.FTP("Your IP address")

ftp.login("Username", "password")

files = []

try:

ftp.cwd("/feed_1")

files = ftp.nlst()

for fname in files:

res = re.findall("2018-07-25", fname)

if res:

print 'Opening local file ' + ntpath.basename(fname)

file = open(ntpath.basename(fname), 'wb')

print 'Getting ' + ntpath.basename(fname)

try:

widgets = ['Downloading: ', Percentage(), ' ',

Bar(marker='#',left='[',right=']'),

' ', ETA(), ' ', FileTransferSpeed()]

pbar = ProgressBar(widgets=widgets, maxval=500)

pbar.start()

ftp.retrbinary('RETR ' + ntpath.basename(fname), file.write)

except:

pass

print 'Closing file ' + ntpath.basename(fname)

file.close()

print (fname)

time.sleep(0.2)

pbar.update()

pbar.finish()

if not res:

continue

except ftplib.error_perm , resp:

if str(resp) == "550 No files found":

print "No files in this directory"

pass

else:

raise

请帮助理解这里的实际错误.谢谢 ：)

解决方法:

您永远不会更新ProgressBar.你需要做的是：

>实现一个函数(或类方法),您将传递给FTP.retrbinary作为回调而不是file.write.该函数应该执行file.write并更新进度条.

>您还需要知道ProgressBar的maxval参数的文件/传输大小.为此你可以使用FTP.size.

一个简单的实现就像：

local_path = "archive.zip"

remote_path = "/remote/path/archive.zip"

file = open(local_path, 'wb')

size = ftp.size(remote_path)

pbar = ProgressBar(widgets = widgets, maxval = size)

pbar.start()

def file_write(data):

file.write(data)

global pbar

pbar += len(data)

ftp.retrbinary("RETR " + remote_path, file_write)

现在你得到了你想要的进度条：

Downloading: 72% [############################### ] ETA: 0:00:00 242.1 MiB/s

标签：python,download,ftp,ftplib,progress-bar

来源： https://codeday.me/bug/20191001/1839874.html