python3小demo

　　总结常用的功能小实例,快速学习并掌握python技能

1.墨迹天气

import requests
from lxml.html import etree
import json
import time        # 导入模块
class MoJiWeather():
    def city_name(self):  # 定义一个输入城市名称的函数
        cityname = str(input("输入城市名称："))
        return cityname
    def search_city(city_name):# 搜索这个城市
        index_url = "http://tianqi.moji.com/api/citysearch/%s"%city_name   #  构造查询相应城市天气的url
        response = requests.get(index_url)
        response.encoding = "utf-8"
        try:# 异常捕获
            city_id = json.loads(response.text).get('city_list')[].get('cityId')# 通过上面的url获取城市的id
            city_url = "http://tianqi.moji.com/api/redirect/%s"%str(city_id)  # 通过城市id获取城市天气
            return city_url
        except:
            print('城市名输入错误')
            exit()
    def parse(city_url):# 解析函数
        response = requests.get(city_url)
        response.encoding = 'utf-8'
        html = etree.HTML(response.text)
        current_city = html.xpath("//div[@class='search_default']/em/text()")[]#    下面都是利用xpath解析的
        print('当前城市：'+current_city)
        current_kongqi = html.xpath("//div[@class='left']/div[@class='wea_alert clearfix']/ul/li/a/em/text()")[]
        print('空气质量：'+current_kongqi)
        current_wendu = html.xpath("//div[@class='left']/div[@class='wea_weather clearfix']/em/text()")[]
        print('当前温度：'+current_wendu+'℃')
        current_weather = html.xpath("//div[@class='wea_weather clearfix']/b/text()")[]
        print('天气状况：' + current_weather)
        current_shidu = html.xpath("//div[@class='left']/div[@class='wea_about clearfix']/span/text()")[]
        print('当前湿度：'+current_shidu)
        current_fengji = html.xpath("//div[@class='left']/div[@class='wea_about clearfix']/em/text()")[]
        print('当前风速：'+current_fengji)
        jingdian = html.xpath("//div[@class='right']/div[@class='near'][2]/div[@class='item clearfix']/ul/li/a/text()")
        print('附近景点：')
        for j in jingdian:
            print('\t\t'+j)
if __name__ == '__main__':
    print("欢迎使用墨迹天气查询系统")
    city_name = MoJiWeather.city_name()
    city_url = MoJiWeather.search_city(city_name)
    MoJiWeather.parse(city_url)
    print("谢谢使用本查询系统")
    input("按任意键退出...")

2.Tiobe排行榜

import json
from lxml import etree
from lxml.etree import ParseError
import requests
from requests.exceptions import RequestException
 
'''
    lxml实例应用
'''
 
'''
    获取页面数据
'''
def one_to_page(url):
    headers = {
        'user-agent': 'Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/67.0.3396.62 Safari/537.36'
    }
 
    try:
        res = requests.get(url,headers=headers)
        body = res.text #获取网页内容
    except RequestException as e:
        print('request is error',e)
 
    try:
        html = etree.HTML(body,etree.HTMLParser())
        # tr 下的所有子孙节点(只获取文本数,图片资源不获取)
        result = html.xpath('//table[contains(@class,"table-top20")]/tbody/tr//text()')
 
        pos =
        for i in range():
            if i == :
                yield result[i:]
            else:
                yield result[pos:pos+]
            pos += 
 
    except ParseError as e:
        print(e.position)
 
'''
    写入文件
'''
def write_file(data):
    for item in data:
        sul = {
            '2018年6月排行': item[],
            '2017年6排行': item[],
            '开发语言': item[],
            '评级': item[],
            '变化率': item[]
        }
        # with 更好处理异常情况,进行文件的关闭后续工作
        with open('test.txt','a',encoding='utf-8') as f:
            f.write(json.dumps(sul,ensure_ascii=False)+'\n')
            f.close()
        print(sul)
    return None
 
'''
    主程序
'''
def main():
    url = 'https://www.tiobe.com/tiobe-index/'
    data = one_to_page(url)
    ret = write_file(data)
    if ret == None:
        print('ok')
 
if __name__ == '__main__':
    main()

3.新闻列表

'''
    墨迹天气文章爬虫
'''
import requests
import json
from lxml.html import etree
from lxml.etree import ParseError
 
'''
    解析页面内容
'''
def parseHtml(content):
    try:
        html = etree.HTML(content,etree.HTMLParser())
        # one = html.xpath('//ul[@class="advisory_list_item"]//text()')
        one = html.xpath('//ul[@class="advisory_list_item"]//li/a/@href')
        print(one)
        exit()
        LOOP =
        pos =
        for i in range():
            if i == :
                yield one[:LOOP]
            else:
                yield one[pos:pos+LOOP]
            pos += LOOP
 
    except ParseError as e:
        print(e.position)
 
'''
    写入文件
'''
def write_log(data):
    for item in data:
        msg = {
            '发文时间':item[],
            '文章标题':item[]
        }
        with open('moji.log','a',encoding='utf-8') as f:
            f.write(json.dumps(msg,ensure_ascii=False)+'\n')
            f.close()
        print(msg)
    return None
'''
    主程序
'''
def main():
 
    for page in range(,):
        url = 'https://tianqi.moji.com/news/list/moji/{}'.format(page)
        res = requests.get(url)
        res.encoding = 'utf-8'
        content = parseHtml(res.text)
        ret = write_log(content)
        if ret is None:
            print('ok')
 
if __name__ == '__main__':
    main()

4.爬取IP

import requests
import re
import random
 
from bs4 import BeautifulSoup
 
ua_list = [
    "Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/72.0.3626.109 Safari/537.36",
    "Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/62.0.3202.75 Safari/537.36",
    "Mozilla/5.0 (Macintosh; Intel Mac OS X 10_13_6) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/72.0.3626.119 Safari/537.36",
    "Mozilla / 5.0(Windows NT 6.1;WOW64) AppleWebKit / 537.36(KHTML, likeGecko) Chrome / 45.0.2454.101Safari / 537.36"
    ]
 
def ip_parse_xici(page):
    """
 
    :param page: 采集的页数
    :return:
    """
    ip_list = []
    for pg in range(, int(page)):
        url = 'http://www.xicidaili.com/nn/' + str(pg)
        user_agent = random.choice(ua_list)
        my_headers = {
            'Accept': 'text/html, application/xhtml+xml, application/xml;',
            'Accept-Encoding': 'gzip, deflate, sdch',
            'Accept-Language': 'zh-CN,zh;q=0.8',
            'Referer': 'http: // www.xicidaili.com/nn',
            'User-Agent': user_agent
        }
        try:
            r = requests.get(url, headers=my_headers)
            soup = BeautifulSoup(r.text, 'html.parser')
        except requests.exceptions.ConnectionError:
            print('ConnectionError')
        else:
            data = soup.find_all('td')
            # 定义IP和端口Pattern规则
            ip_compile = re.compile(r'<td>(\d+\.\d+\.\d+\.\d+)</td>')  # 匹配IP
            port_compile = re.compile(r'<td>(\d+)</td>')  # 匹配端口
            ips = re.findall(ip_compile, str(data))  # 获取所有IP
 
            ports = re.findall(port_compile, str(data))  # 获取所有端口
            check_api = "http://ip.taobao.com/service/getIpInfo2.php?ip="
 
            for i in range(len(ips)):
                if i < len(ips):
                    ip = ips[i]
                    api = check_api + ip
                    api_headers = {
                        'User-Agent': user_agent
                    }
                    try:
                        response = requests.get(url=api, headers=api_headers, timeout=)
                        print("ip：%s 可用" % ip)
                    except Exception as e:
                        print("此ip %s 已失效：%s" % (ip, e))
                        del ips[i]
                        del ports[i]
            ips_usable = ips
            ip_list += [':'.join(n) for n in zip(ips_usable, ports)]  # 列表生成式
            print('第{}页ip采集完成'.format(pg))
    print(ip_list)
 
if __name__ == '__main__':
    xici_pg = input("请输入需要采集的页数：")
    ip_parse_xici(page=xici_pg)