新手学习Python笔记（一）爬虫的简单应用_网易云音乐热评

新手学习Python笔记（一）爬虫的简单应用

免责声明：本程序仅供个人学习使用

功能目标：方便摘抄网易云音乐的热评，写一个爬虫程序，通过输入歌单号，爬取并保存歌单内歌曲的热评。

记录第一个自己完成的简单爬虫程序

展示截图：（命令台界面和保存文件界面）

顺便安利一下这个日语歌单

下面是代码部分：

库：requests、bs4 、json、csv、time（可选）

import requests
from bs4 import BeautifulSoup
import json
from csv import writer
import time

t1=time.clock()
headers = {
'User-Agent': 'Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/62.0.3202.75 Safari/537.36',
}

print("===========================\n获取网易云音乐歌单中所有歌曲热评\n===========================")
id= input("请输入歌单id：")
print("正在搜索。。。\n")

playlist_url = f'http://music.163.com/playlist?id={id}'

rs = requests.session()
r = rs.get(playlist_url, headers=headers)

soup = BeautifulSoup(r.content, 'lxml')

main = soup.find('ul', {'class': 'f-hide'})

name_list= []
id_list= []

for music in main.find_all('a'):

music_id= music['href'][9:]
music_name= music.text

name_list.append(music_name)
id_list.append(music_id)

total= len(name_list)
cout=1
allcout=0

file= open("网易云音乐歌单热评.csv","w",encoding="gb18030",newline="")
writer= writer(file)

for i in id_list:

list=[cout,name_list[cout-1]]
writer.writerow(list)
get_url= "http://music.163.com/api/v1/resource/comments/R_SO_4_"+i+"?limit=0&offset=0"

r= requests.get(get_url,headers=headers)

json_dict=json.loads(r.content.decode("utf-8"))

hotcomments= json_dict["hotComments"]

allcout+=len(hotcomments)
no=1

for j in hotcomments:
nickname= j["user"]["nickname"]
content= j["content"].replace("\n"," ")
liked= str(j["likedCount"])+"赞"
list=["","",no,nickname,liked,content]
writer.writerow(list)
no+=1
cout+=1
writer.writerow('')
file.close()

t2= time.clock()-t1

print(f"共找到{total}首歌 {allcout}条热评 用时{t2:.2f}s",end="\n===========================\n")
input("按任意键退出。。。")

代码分析：

常量的定义、界面设计

#计时开始
t1=time.clock()
headers = {
'User-Agent': 'Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/62.0.3202.75 Safari/537.36',
}

print("===========================\n获取网易云音乐歌单中所有歌曲热评\n===========================")
id= input("请输入歌单id：")
print("正在搜索。。。\n")

playlist_url = f'http://music.163.com/playlist?id={id}'#得到歌单的url

爬取歌曲信息

#得到歌单内的歌曲名称和歌曲id
rs = requests.session()
r = rs.get(playlist_url, headers=headers)

soup = BeautifulSoup(r.content, 'lxml')

#可通过歌曲网页的源码得到有关信息
main = soup.find('ul', {'class': 'f-hide'})

name_list= []
id_list= []

for music in main.find_all('a'):

music_id= music['href'][9:]
music_name= music.text

name_list.append(music_name)
id_list.append(music_id)

#计数君
total= len(name_list)
cout=1
allcout=0

创建表格

#易错点：encoding，newline应设为""
file= open("网易云音乐歌单热评.csv","w",encoding="gb18030",newline="")
writer= writer(file)

爬取评论信息并保存
核心:此api会返回歌曲评论
“http://music.163.com/api/v1/resource/comments/R_SO_4_”+ id +"?limit=0&offset=0"

#用id查找评论，按照评论顺序记录
for i in id_list:

list=[cout,name_list[cout-1]]
writer.writerow(list)

get_url= "http://music.163.com/api/v1/resource/comments/R_SO_4_"+i+"?limit=0&offset=0"

r= requests.get(get_url,headers=headers)

json_dict=json.loads(r.content.decode("utf-8"))

hotcomments= json_dict["hotComments"]

allcout+=len(hotcomments)
no=1

#从返回的json获取有关信息
for j in hotcomments:
nickname= j["user"]["nickname"]
content= j["content"].replace("\n"," ")
liked= str(j["likedCount"])+"赞"
list=["","",no,nickname,liked,content]
writer.writerow(list)
no+=1

cout+=1

writer.writerow('')
file.close()

结束显示

#计时结束
t2= time.clock()-t1

#计数君
print(f"共找到{total}首歌 {allcout}条热评 用时{t2:.2f}s",end="\n===========================\n")
input("按任意键退出。。。")

缺点分析：当歌曲数量多会导致用时特别长
拓展：多线程爬虫

完

生活的最好状态是冷冷清清的风风火火——木心