·「python爬虫入门」网易云音乐下载

515439429

　　2015-6-2
　　今天把昨天Git上看的一个下载网易云音乐歌单歌曲的脚本尝试看懂并修改
　　Git地址：https://github.com/keli/netease-music





#! /usr/bin/env python
# -*- coding: utf-8 -*-
import urllib2
import json
import os
import sys
import md5
import string
import random
# Set cookie
cookie_opener = urllib2.build_opener()
cookie_opener.addheaders.append(('Cookie', 'appver=2.0.2'))
cookie_opener.addheaders.append(('Referer', 'http://music.163.com'))
urllib2.install_opener(cookie_opener)
def encrypted_id(id):
byte1 = bytearray('3go8&$8*3*3h0k(2)2')
byte2 = bytearray(id)
byte1_len = len(byte1)
for i in xrange(len(byte2)):
byte2 = byte2^byte1[i%byte1_len]
m = md5.new()
m.update(byte2)
result = m.digest().encode('base64')[:-1]
result = result.replace('/', '_')
result = result.replace('+', '-')
return result
def get_playlist(playlist_id):
url = 'http://music.163.com/api/playlist/detail?id=%s' % playlist_id
resp = urllib2.urlopen(url)
data = json.loads(resp.read())
return data['result']
def save_track(track, folder, position):
name = track['hMusic']['name']
if position < 10:
pos = "0%d" % position
else:
pos = "%d" % position
#fname = pos + ' ' + name + track['hMusic']['extension']
fname = name + '.' + track['hMusic']['extension']
fname = string.replace(fname, '/', '_')
fpath = os.path.normpath(os.path.join(folder, fname))
if os.path.exists(fpath):
return
print "Downloading", fpath, "..."
dfsId = str(track['hMusic']['dfsId'])
url = 'http://m%d.music.126.net/%s/%s.%s' % (random.randrange(1, 3), encrypted_id(dfsId), dfsId, track['hMusic']['extension'])
resp = urllib2.urlopen(track['mp3Url'])
data = resp.read()
resp.close()
with open(fpath, 'wb') as mp3:
mp3.write(data)
def download_playlist(playlist_id, folder='.'):
playlist = get_playlist(playlist_id)
name = playlist['name']
folder = os.path.join(folder, name)
if not os.path.exists(folder):
os.makedirs(folder)
for idx, track in enumerate(playlist['tracks']):
save_track(track, folder, idx+1)
if __name__ == '__main__':
if len(sys.argv) < 2:
print "Usage: %s <playlist id>" % sys.argv[0]
sys.exit(1)
download_playlist(sys.argv[1])
View Code　　这边是对cookie的处理，addheaders的方法之前没有看到过，help查询居然也没有查到，但是有用



cookie_opener = urllib2.build_opener()
cookie_opener.addheaders.append(('Cookie', 'appver=2.0.2'))
cookie_opener.addheaders.append(('Referer', 'http://music.163.com'))
urllib2.install_opener(cookie_opener)
　　这一段其实是没有用的，但是挺好奇这段代码里面函数的作用，过段时间再去学一下



def encrypted_id(id):
byte1 = bytearray('3go8&$8*3*3h0k(2)2')
byte2 = bytearray(id)
byte1_len = len(byte1)
for i in xrange(len(byte2)):
byte2 = byte2^byte1[i%byte1_len]
m = md5.new()
m.update(byte2)
result = m.digest().encode('base64')[:-1]
result = result.replace('/', '_')
result = result.replace('+', '-')
return result
　　
　　下面这段代码是发挥主要作用的，但是这个脚本是原作者三个月前写的，网易云音乐应该有一些变化



def get_playlist(playlist_id):
url = 'http://music.163.com/api/playlist/detail?id=%s' % playlist_id
resp = urllib2.urlopen(url)
data = json.loads(resp.read())
return data['result']
def save_track(track, folder, position):
name = track['hMusic']['name']
if position < 10:
pos = "0%d" % position
else:
pos = "%d" % position
#fname = pos + ' ' + name + track['hMusic']['extension']
fname = name + '.' + track['hMusic']['extension']
fname = string.replace(fname, '/', '_')
fpath = os.path.normpath(os.path.join(folder, fname))
if os.path.exists(fpath):
return
print "Downloading", fpath, "..."
dfsId = str(track['hMusic']['dfsId'])
url = 'http://m%d.music.126.net/%s/%s.%s' % (random.randrange(1, 3), encrypted_id(dfsId), dfsId, track['hMusic']['extension'])
resp = urllib2.urlopen(track['mp3Url'])
data = resp.read()
resp.close()
with open(fpath, 'wb') as mp3:
mp3.write(data)
def download_playlist(playlist_id, folder='.'):
playlist = get_playlist(playlist_id)
name = playlist['name']
folder = os.path.join(folder, name)
if not os.path.exists(folder):
os.makedirs(folder)
for idx, track in enumerate(playlist['tracks']):
save_track(track, folder, idx+1)
　　首先是JSON，我之前并没有学过JSON，XML也只是昨天看了一小会儿
　　http://music.163.com/api/playlist/detail?id=4566307 打开准备下载的歌单
　　用Firebug看Json挺清晰，结构都很清楚，chrome就感觉有点一堆凑一起
　　看代码也知道歌曲的链接在tracks里面
　　我按着原作者的代码调试 发现一直卡在



name = track['hMusic']['name']
　　后来调了半天，才去JSON文件里看了，发现tracks里面不是所有歌曲都有 hMusic 这个 属性
　　后来直接改成  name = track['name']
　　而且再仔细看JSON 发现代码有好几处不对的地方 最后改成了这样



ef get_playlist(playlist_id):
url = 'http://music.163.com/api/playlist/detail?id=%s' % playlist_id
resp = urllib2.urlopen(url)
data = json.loads(resp.read())
print data['result']['name']
return data['result']
def save_track(track, folder, position):
name = track['name'] #name = track['hMusic']['name']
print name
if position < 10:
pos = "0%d" % position
else:
pos = "%d" % position
#fname = pos + ' ' + name + track['hMusic']['extension']
fname = name + str(position) + '.mp3' #fname = name + str(position) + '.' + track['hMusic']['extension']
fname = string.replace(fname, '/', '_')
fpath = os.path.normpath(os.path.join(folder, fname))
if os.path.exists(fpath):
return
print "Downloading", fpath, "..."
# dfsId = str(track['hMusic']['dfsId'])
# url = 'http:/7m%d.music.126.net/%s/%s.%s' % (random.randrange(1, 3), encrypted_id(dfsId), dfsId, track['hMusic']['extension'])
try:
resp = urllib2.urlopen(track['mp3Url'], timeout = 5)
data = resp.read()
resp.close()
except urllib2.URLError as e:
print type(e)    #not catch
pass
except socket.timeout as e:
print type(e)    #catched
pass  
else:
with open(fpath, 'wb') as mp3:
mp3.write(data)

def download_playlist(playlist_id, folder='.'):
playlist = get_playlist(playlist_id)
name = playlist['name']
folder = os.path.join(folder, name)
if not os.path.exists(folder):
os.makedirs(folder)
for idx, track in enumerate(playlist['tracks']):
print 'begin save'
save_track(track, folder, idx+1)
　　注释掉的部分就是更改的地方
　　在下载歌曲的时候，经常会卡在一个地方，然后知道urlopen可以设置timeout 就是超时时间，
　　然后我的想法是超时的话就报错然后继续下载下一首
　　但是不是很熟悉try except 试了好久
　　试过好几个版本



try:
resp = urllib2.urlopen(track['mp3Url'], timeout = 5)
data = resp.read()
resp.close()
except urllib2.URLError as e:
print type(e)    #not catch
pass
except socket.timeout as e:
print type(e)    #catched
pass  
with open(fpath, 'wb') as mp3:
mp3.write(data)


try:
resp = urllib2.urlopen(track['mp3Url'], timeout = 5)
data = resp.read()
resp.close()
except urllib2.URLError as e:
print type(e)    #not catch
except socket.timeout as e:
print type(e)    #catched
else:
with open(fpath, 'wb') as mp3:
mp3.write(data)


try:
resp = urllib2.urlopen(track['mp3Url'], timeout = 5)
except urllib2.URLError as e:
print type(e)    #not catch
pass
except socket.timeout as e:
print type(e)    #catched
pass  
data = resp.read()
resp.close()
with open(fpath, 'wb') as mp3:
mp3.write(data)
　　总之都是代码报错，报错了也没有继续运行下去
　　后来改成这样



    try:
resp = urllib2.urlopen(track['mp3Url'], timeout = 5)
data = resp.read()
resp.close()
except urllib2.URLError as e:
print type(e)    #not catch
pass
except socket.timeout as e:
print type(e)    #catched
pass  
else:
with open(fpath, 'wb') as mp3:
mp3.write(data)
　　就行了=。=， 还是得再好好看看异常处理那一块
　　
　　总之这就是一下午的学习，虽然下歌什么的对我并没有什么卵用