利用Python如何实现根据URL地址下载并保存文件至对应目录

发布时间：2020-11-16 14:23:11

来源：亿速云

阅读：58

作者：Leah

这篇文章将为大家详细讲解有关利用Python如何实现根据URL地址下载并保存文件至对应目录，文章内容质量较高，因此小编分享给大家做个参考，希望大家阅读完这篇文章后对相关知识有一定的了解。

引言

在编程中经常会遇到图片等数据集将图片等数据以URL形式存储在txt文档中，为便于后续的分析，需要将其下载下来，并按照文件夹分类存储。本文以Github中Alexander Kim提供的图片分类数据集为例，下载其提供的图片样本并分类保存

Python 3.6.5，Anaconda， VSCode

1. 下载数据集文件

建立项目文件夹，下载上述Github项目中的raw_data文件夹，并保存至项目目录中。

2. 获取样本文件位置

编写get_doc_path.py，根据根目录位置，获取目录及其子目录所有数据集文件

import os

def get_file(root_path, all_files={}):

'''

递归函数，遍历该文档目录和子目录下的所有文件，获取其path

'''

files = os.listdir(root_path)

for file in files:

if not os.path.isdir(root_path + '/' + file): # not a dir

all_files[file] = root_path + '/' + file

else: # is a dir

get_file((root_path+'/'+file), all_files)

return all_files

if __name__ == '__main__':

path = './raw_data'

print(get_file(path))

3. 下载文件

3.1 读取url列表并

for filename, path in paths.items():

print('reading file: {}'.format(filename))

with open(path, 'r') as f:

lines = f.readlines()

url_list = []

for line in lines:

url_list.append(line.strip('\n'))

print(url_list)

3.2 创建文件夹

foldername = "./picture_get_by_url/pic_download/{}".format(filename.split('.')[0])

if not os.path.exists(folder_path):

print("Selected folder not exist, try to create it.")

os.makedirs(folder_path)

3.3 下载图片

def get_pic_by_url(folder_path, lists):

if not os.path.exists(folder_path):

print("Selected folder not exist, try to create it.")

os.makedirs(folder_path)

for url in lists:

print("Try downloading file: {}".format(url))

filename = url.split('/')[-1]

filepath = folder_path + '/' + filename

if os.path.exists(filepath):

print("File have already exist. skip")

else:

try:

urllib.request.urlretrieve(url, filename=filepath)

except Exception as e:

print("Error occurred when downloading file, error message:")

print(e)

4. 完整源码

4.1 get_doc_path.py

import os

def get_file(root_path, all_files={}):

'''

递归函数，遍历该文档目录和子目录下的所有文件，获取其path

'''

files = os.listdir(root_path)

for file in files:

if not os.path.isdir(root_path + '/' + file): # not a dir

all_files[file] = root_path + '/' + file

else: # is a dir

get_file((root_path+'/'+file), all_files)

return all_files

if __name__ == '__main__':

path = './raw_data'

print(get_file(path))

4.2 get_pic.py

import get_doc_path

import os

import urllib.request

def get_pic_by_url(folder_path, lists):

if not os.path.exists(folder_path):

print("Selected folder not exist, try to create it.")

os.makedirs(folder_path)

for url in lists:

print("Try downloading file: {}".format(url))

filename = url.split('/')[-1]

filepath = folder_path + '/' + filename

if os.path.exists(filepath):

print("File have already exist. skip")

else:

try:

urllib.request.urlretrieve(url, filename=filepath)

except Exception as e:

print("Error occurred when downloading file, error message:")

print(e)

if __name__ == "__main__":

root_path = './picture_get_by_url/raw_data'

paths = get_doc_path.get_file(root_path)

print(paths)

for filename, path in paths.items():

print('reading file: {}'.format(filename))

with open(path, 'r') as f:

lines = f.readlines()

url_list = []

for line in lines:

url_list.append(line.strip('\n'))

foldername = "./picture_get_by_url/pic_download/{}".format(filename.split('.')[0])

get_pic_by_url(foldername, url_list)

4.3 运行结果

执行get_pic.py

当程序意外停止或再次执行时，程序会自动跳过文件夹中已下载的文件，继续下载未下载的内容{‘urls_drawings.txt': ‘./picture_get_by_url/raw_data/drawings/urls_drawings.txt', ‘urls_hentai.txt': ‘./picture_get_by_url/raw_data/hentai/urls_hentai.txt', ‘urls_neutral.txt': ‘./picture_get_by_url/raw_data/neutral/urls_neutral.txt', ‘urls_porn.txt': ‘./picture_get_by_url/raw_data/porn/urls_porn.txt', ‘urls_sexy.txt': ‘./picture_get_by_url/raw_data/sexy/urls_sexy.txt'}

reading file: urls_drawings.txt

Try downloading file: http://41.media.tumblr.com/xxxxxx.jpg

Try downloading file: http://41.media.tumblr.com/xxxxxx.jpg

Try downloading file: http://ak1.polyvoreimg.com/cgi/img-thing/size/l/tid/xxxxxx.jpg

Error occurred when downloading file, error message:

HTTP Error 502: No data received from server or forwarder

Try downloading file: http://akicocotte.weblike.jp/gaugau/xxxxxx.jpg

Try downloading file: http://animewriter.files.wordpress.com/2009/01/nagisa-xxxxxx-xxxxxx.jpg

Try downloading file: http://cdn.awwni.me/xxxxxx.jpg

Try downloading file: http://cdn.awwni.me/xxxxxx.jpg

Try downloading file: http://cdn.awwni.me/xxxxxx.jpg

Try downloading file: http://cdn.awwni.me/xxxxxx.jpg

Try downloading file: http://cdn.awwni.me/xxxxxx.jpg

Try downloading file: http://cdn.awwni.me/xxxxxx.jpg

Try downloading file: http://cdn.awwni.me/xxxxxx.jpg

Try downloading file: http://cdn.awwni.me/xxxxxx.jpg

Try downloading file: http://cdn.awwni.me/xxxxxx.jpg

Try downloading file: http://cdn.awwni.me/xxxxxx.jpg

Try downloading file: http://cdn.awwni.me/xxxxxx.jpg

Try downloading file: http://cdn.awwni.me/xxxxxx.jpg

Try downloading file: http://cdn.awwni.me/xxxxxx.jpg

Try downloading file: http://cdn.awwni.me/xxxxxx.jpg

Try downloading file: http://cdn.awwni.me/xxxxxx.jpg

Try downloading file: http://cdn.awwni.me/xxxxxx.jpg

Try downloading file: http://cdn.awwni.me/xxxxxx.jpg

关于利用Python如何实现根据URL地址下载并保存文件至对应目录就分享到这里了，希望以上内容可以对大家有一定的帮助，可以学到更多知识。如果觉得文章不错，可以把它分享出去让更多的人看到。