猫眼电影 Top100

猫眼电影 Top100

思路

1. 获取单页网页源代码并返回源代码
2. 解析单页网页源代码，提取 title、actor、time、score 等数据并存储为生成器
3. 将生成器里每一部电影的数据写入txt文档中
4. 研究第 1-10 页 url 的规律，构建 url，调用 1、2、3 步骤

步骤

获取单页网页源代码并返回源代码

import requests
import re
import json
from requests.exceptions import RequestException

def get_one_page(url):
    headers = {'user-agent': 'Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/70.0.3538.67 Safari/537.36'}
    try:
        response = requests.get(url,headers = headers)
        if response.status_code == 200:
            html = response.text
            return html
        return None
    except RequestException:
        return None

• 打印第一页源码

print(get_one_page('http://maoyan.com/board/4'))

解析单页网页源代码，提取title、actor、time、score数据并存储为生成器

def parse_one_page(html):
    pattern = re.compile('<dd>.*?board-index.*?>(\d+)</i>'
    + '.*?<p.*?title="(.*?)".*?</p>.*?star">(.*?)</p>'
    + '.*?releasetime">(.*?)</p>.*?integer">(.*?)'
    + '<.*?fraction">(.*?)</i>',re.S)
    movies = re.findall(pattern,html)
    for item in movies:
        yield{
            '排名':item[0],
            '电影名':item[1],
            '主演':item[2].strip()[3:],
            '上映时间':item[3][5:],
            '评分':item[4]+item[5]
        }

注意一下，这里需要用 yield，而不是return。yield函数返回的是一个生成器（一种特殊的迭代器，可以用for循环进行遍历）
如果用return，那么在第一轮循环结束就会跳出，只能获取到一部影片的信息

将生成器数据写入 txt 文档

def write_to_txt(content):
    # 采用 append 追加模式，字符集为utf8
    with open('movies.txt','a',encoding='utf8') as f:
        # 采用json的dumps方法来初始化字符串
        f.write(json.dumps(content,ensure_ascii=False) + '\n')
        f.close()

研究第1-10页

# 第1-10页url
for i in range(0,10):
    url = 'https://maoyan.com/board/4?offset=' + str(i * 10)
    # 构建 url，调用1、2、3步骤
    html = get_one_page(url)
    movies= parse_one_page(html)
    for item in movies:
        write_to_txt(item)

多线程保持为 txt

• 第一步

import requests
import re
import json
from multiprocessing import Pool
from requests.exceptions import RequestException

def get_one_page(url):
    headers = {'user-agent': 'Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/70.0.3538.67 Safari/537.36'}
    try:
        response = requests.get(url,headers = headers)
        if response.status_code == 200:
            html = response.text
            return html
        return None
    except RequestException:
        return None

• 第二步

def main(offset):
    url = 'http://maoyan.com/board/4?offset=' + str(offset)
    html = get_one_page(url)
    for item in parse_one_page(html):
        print(item)
        write_to_txt(item)

if __name__ == '__main__':
    pool = Pool() # 多线程
    pool.map(main, [i*10 for i in range(10)])
    pool.close()
    pool.join()

保持为 CSV

单线程

import requests
import re
import json
import pandas
from requests.exceptions import RequestException

def get_one_page(url):
    headers = {'user-agent': 'Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/70.0.3538.67 Safari/537.36'}
    response = requests.get(url,headers = headers)
    html = response.text
    return html

def parse_one_page(html):
    pageary = []
    pattern = re.compile('<dd>.*?board-index.*?>(\d+)</i>'
    + '.*?<p.*?title="(.*?)".*?</p>.*?star">(.*?)</p>'
    + '.*?releasetime">(.*?)</p>.*?integer">(.*?)'
    + '<.*?fraction">(.*?)</i>',re.S)
    movies = re.findall(pattern,html)
    for item in movies:
        dict = {
            '电影名':item[0],
            '主演':item[1].strip()[3:],
            '上映时间':item[2][5:],
            '评分':item[3]+item[4]
        }
        pageary.append(dict)
    return pageary

ary = []
for i in range(0,10):
    url = 'https://maoyan.com/board/4?offset=' + str(i * 10)
    html = get_one_page(url)
    pageary = parse_one_page(html)
    ary = ary + pageary
df = pandas.DataFrame(ary)
df.to_csv('movies.csv')

多线程

import requests
import re
import json
import pandas
from multiprocessing import Pool
from requests.exceptions import RequestException

def get_one_page(url):
    headers = {'user-agent': 'Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/70.0.3538.67 Safari/537.36'}
    try:
        response = requests.get(url,headers = headers)
        if response.status_code == 200:
            html = response.text
            return html
        return None
    except RequestException:
        return None

def parse_one_page(html):
    pageary = []
    pattern = re.compile('<dd>.*?board-index.*?>(\d+)</i>'
    + '.*?<p.*?title="(.*?)".*?</p>.*?star">(.*?)</p>'
    + '.*?releasetime">(.*?)</p>.*?integer">(.*?)'
    + '<.*?fraction">(.*?)</i>',re.S)
    movies = re.findall(pattern,html)
    for item in movies:
        dict = {
            '排名':item[0],
            '电影名':item[1],
            '主演':item[2].strip()[3:],
            '上映时间':item[3][5:],
            '评分':item[4]+item[5]
        }
        pageary.append(dict)
    return pageary

def write_to_csv(pageary):
    ary = []
    ary = ary + pageary
    df = pandas.DataFrame(ary)
    df.to_csv('movies.csv')

def main(offset):
    url = 'https://maoyan.com/board/4?offset=' + str(offset)
    pageary = parse_one_page(html)
    write_to_csv(ary)

if __name__ == '__main__':
    pool = Pool()
    pool.map(main, [i*10 for i in range(10)])
    pool.close()
    pool.join()