python网页爬虫开发之七-多线程爬虫示例01

from urllib.request import quote
import urllib.request
from bs4 import BeautifulSoup
import re
import multiprocessing
import os
import time
 
def start():
    for txt in range(0, 999):
        start = int(input("请输入开始章节(从1开始):"))-1
        if start < 0 or start > len(chapter_link)-1:
            print("开始章节错误,请重新输入")
        else:
            break
    return start
def end():
    for txt in range(0, 999):
        end = int(input("请输入最后章节(最大为总章节数):"))-1
        if end < 0 or end > len(chapter_link)-1:
            print("结束章节错误,请重新输入")
        else:
            break
    return end
def all():
    filter_chapter_link = r'<a href="(.+?)">.+?</a>'
    book_txt = str(soup.find_all(name="a", attrs={"href": re.compile(r"/w+/w+.html")}))
    chapter_link_1 = re.findall(filter_chapter_link, book_txt) # 链接
    chapter_link_2 = "http://www.x23us.us" + " http://www.x23us.us".join(chapter_link_1)
    chapter_link = chapter_link_2.split(' ')
    name=soup.h1.string
    return chapter_link,name
def chapter():
    links=[]
    i=0
    for link_chapter in range(start,end+1):
        links.append(chapter_link[start+i])
        i=i+1
    return links
def mkdir(path):
    floder=os.path.exists(path)
    if not floder:
        os.makedirs(path)
        print("创建成功")
    else:
        print("文件已存在")
def remadir():
    img_path2 = "E:/txt/" + name
    if not os.path.exists(img_path2):
        os.rename(img_path, img_path2)
        print("已全部下载完成!")
    else:
        downloadtime = time.strftime("%Y%m%d%I%M%S", time.localtime())
        os.rename(img_path, img_path2 + downloadtime)
        print("已全部下载完成! "+"文件名:" +name + " 已存在,重命名为:" + name+ downloadtime + " " + "请勿重复操作")
 
def download(url):
    req = urllib.request.Request(url) # 请求链接
    req.add_header = {
        'User-Agent': 'Mozilla/5.0 (Windows NT 6.1; WOW64; rv:30.0) Gecko/20100101 Firefox/30.0'} # 添加数据头
    page = urllib.request.urlopen(req).read()
    html = page.decode('gbk')
    soup = BeautifulSoup(html, "html.parser")
    book_txt = soup.find_all(name="div", attrs={"id": "content"})
    txt = soup.find_all(name="h1")
    name=re.sub(r'<h1>|</h1>||/|<|>|:|?|*|"||', '',str(txt[0]))
    filter_order = r'http://www.x23us.us/.+?/(.+?).html'
    order = re.findall(filter_order, url)[0]
    book = name+" "+(
        re.sub(r'<div id="content" name="content">|</div>|<br/> <br/>| | ', '', str(book_txt[0]))).strip()+" " # 对过滤和编辑
    f = open("E:/txt/txt/" + order+".txt", "a") # a代表追加模式,不覆盖
    f.write(book.encode('gbk', 'ignore').decode('gbk'))
    f.close()
    print(name+"下载完成")
 
def change():
    txtname = os.listdir("E:/txt/"+name+"/")
    i = 0
    txts = []
    for txt in range(0, len(txtname)):
        a = "E:/txt/"+name+"/"+txtname[i]
        f1 = open(a, "r")
        lines = f1.readlines()
        o= " " + "".join(lines)
        txts.append(o)
        f1.close()
        os.remove(a)
        i = i + 1
    txts1 = "".join(txts)
    g = open("E:/txt/"+name+"/"+name+".txt", "a")
    g.write(txts1)
    g.close()
if __name__ == '__main__':
    for txt in range(0, 999):
        a = quote(input("请输入书名(精确):").encode('GBK')) # 接受一个值,编码为GBK,再转换为url编码 (顶点的编码为GBK,UTF-8和GBK的url编码不一样)
        if len(a) > 1:
            url = "http://www.x23us.us/modules/article/search.php?searchkey=" + a # 搜索的链接
            req = urllib.request.Request(url) # 请求链接
            req.add_header = {
                'User-Agent': 'Mozilla/5.0 (Windows NT 6.1; WOW64; rv:30.0) Gecko/20100101 Firefox/30.0'} # 添加数据头
            page = urllib.request.urlopen(req).read() # 打开链接,并读取
            html = page.decode('gbk') # 顶点编码为gbk,把显示的内容转换为gbk编码
            soup = BeautifulSoup(html, "html.parser")
            b = len(soup.find_all(name="div", attrs={"class": "layout"}))
            if b == 0:
                print("搜索成功")
                break
            else:
                print("无结果,请重新输入!")
        else:
            print("请输入至少2个字符长度!")
    chapter_link=all()[0]
    name=all()[1]
    print("一共有" + str(len(chapter_link)) + "章")
    start=start()
    end=end()
    img_path = "E:/txt/txt/"
    mkdir(img_path)
    links = chapter()
    pool = multiprocessing.Pool(processes=10)
    pool.map(download, links)
    pool.close()
    pool.join()
    remadir()
    change()
    time.sleep(5)
原文地址:https://www.cnblogs.com/joxin/p/9850922.html