6.20-python学习
一.今日内容:
1.解析库之bs4:
'''''' ''' pip3 install beautifulsoup4 # 安装bs4 pip3 install lxml # 下载lxml解析器 ''' html_doc = """ <html><head><title>The Dormouse's story</title></head> <body> <p class="sister"><b>$37</b></p> <p class="story" id="p">Once upon a time there were three little sisters; and their names were <a href="http://example.com/elsie" class="sister" >Elsie</a>, <a href="http://example.com/lacie" class="sister" id="link2">Lacie</a> and <a href="http://example.com/tillie" class="sister" id="link3">Tillie</a>; and they lived at the bottom of a well.</p> <p class="story">...</p> """ # 从bs4中导入BeautifulSoup from bs4 import BeautifulSoup # 调用BeautifulSoup实例化得到一个soup对象 # 参数一: 解析文本 # 参数二: # 参数二: 解析器(html.parser、lxml...) soup = BeautifulSoup(html_doc, 'lxml') print(soup) print('*' * 100) print(type(soup)) print('*' * 100) # 文档美化 html = soup.prettify() print(html)
2.bs之遍历文档树:
html_doc = """<html><head><title>The Dormouse's story</title></head><body><p class="sister"><b>$37</b></p><p class="story" id="p">Once upon a time there were three little sisters; and their names were<b>tank</b><a href="http://example.com/elsie" class="sister" >Elsie</a>,<a href="http://example.com/lacie" class="sister" id="link2">Lacie</a> and<a href="http://example.com/tillie" class="sister" id="link3">Tillie</a>;and they lived at the bottom of a well.<hr></hr></p><p class="story">...</p>""" from bs4 import BeautifulSoup soup = BeautifulSoup(html_doc, 'lxml') ''' 遍历文档树: 1、直接使用 2、获取标签的名称 3、获取标签的属性 4、获取标签的内容 5、嵌套选择 6、子节点、子孙节点 7、父节点、祖先节点 8、兄弟节点 ''' # 1、直接使用 print(soup.p) # 查找第一个p标签 print(soup.a) # 查找第一个a标签 # 2、获取标签的名称 print(soup.head.name) # 获取head标签的名称 # 3、获取标签的属性 print(soup.a.attrs) # 获取a标签中的所有属性 print(soup.a.attrs['href']) # 获取a标签中的href属性 # 4、获取标签的内容 print(soup.p.text) # $37 # 5、嵌套选择 print(soup.html.head) # 6、子节点、子孙节点 print(soup.body.children) # body所有子节点,返回的是迭代器对象 print(list(soup.body.children)) # 强转成列表类型 print(soup.body.descendants) # 子孙节点 print(list(soup.body.descendants)) # 子孙节点 # 7、父节点、祖先节点 print(soup.p.parent) # 获取p标签的父亲节点 # 返回的是生成器对象 print(soup.p.parents) # 获取p标签所有的祖先节点 print(list(soup.p.parents)) # 8、兄弟节点 # 找下一个兄弟 print(soup.p.next_sibling) # 找下面所有的兄弟,返回的是生成器 print(soup.p.next_siblings) print(list(soup.p.next_siblings)) # 找上一个兄弟 print(soup.a.previous_sibling) # 找到第一个a标签的上一个兄弟节点 # 找到a标签上面的所有兄弟节点 print(soup.a.previous_siblings) # 返回的是生成器 print(list(soup.a.previous_siblings))
3.bs之搜索文档树:
'''''' html_doc = """<html><head><title>The Dormouse's story</title></head><body><p class="sister"><b>$37</b></p><p class="story" id="p">Once upon a time there were three little sisters; and their names were<b>tank</b><a href="http://example.com/elsie" class="sister" >Elsie</a>,<a href="http://example.com/lacie" class="sister" id="link2">Lacie</a> and<a href="http://example.com/tillie" class="sister" id="link3">Tillie</a>;and they lived at the bottom of a well.<hr></hr></p><p class="story">...</p>""" ''' 搜索文档树: find() 找一个 find_all() 找多个 标签查找与属性查找: 标签: name 属性匹配 attrs 属性查找匹配 text 文本匹配 - 字符串过滤器 字符串全局匹配 - 正则过滤器 re模块匹配 - 列表过滤器 列表内的数据匹配 - bool过滤器 True匹配 - 方法过滤器 用于一些要的属性以及不需要的属性查找。 属性: - class_ - id ''' from bs4 import BeautifulSoup soup = BeautifulSoup(html_doc, 'lxml') # # 字符串过滤器 # # name p_tag = soup.find(name='p') print(p_tag) # 根据文本p查找某个标签 # 找到所有标签名为p的节点 tag_s1 = soup.find_all(name='p') print(tag_s1) # # # # attrs # # 查找第一个class为sister的节点 p = soup.find(attrs={"class": "sister"}) print(p) # # 查找所有class为sister的节点 tag_s2 = soup.find_all(attrs={"class": "sister"}) print(tag_s2) # # # # text text = soup.find(text="$37") print(text) # # # # 配合使用: # # 找到一个id为link2、文本为Lacie的a标签 a_tag = soup.find(name="a", attrs={"id": "link2"}, text="Lacie") print(a_tag) # # 正则过滤器 import re # name p_tag = soup.find(name=re.compile('p')) print(p_tag) # 列表过滤器 import re # name tags = soup.find_all(name=['p', 'a', re.compile('html')]) print(tags) # - bool过滤器 # True匹配 # 找到有id的p标签 p = soup.find(name='p', attrs={"id": True}) print(p) # 方法过滤器 # 匹配标签名为a、属性有id没有class的标签 def have_id_class(tag): if tag.name == 'a' and tag.has_attr('id') and tag.has_attr('class'): return tag tag = soup.find(name=have_id_class) print(tag)
4.爬取豌豆荚:
''' 主页: 图标地址、下载次数、大小、详情页地址 详情页: 游戏名、图标名、好评率、评论数、小编点评、简介、网友评论、1-5张截图链接地址、下载地址 https://www.wandoujia.com/wdjweb/api/category/more?catId=6001&subCatId=0&page=1&ctoken=FRsWKgWBqMBZLdxLaK4iem9B https://www.wandoujia.com/wdjweb/api/category/more?catId=6001&subCatId=0&page=2&ctoken=FRsWKgWBqMBZLdxLaK4iem9B https://www.wandoujia.com/wdjweb/api/category/more?catId=6001&subCatId=0&page=3&ctoken=FRsWKgWBqMBZLdxLaK4iem9B 32 ''' import requests from bs4 import BeautifulSoup # 1、发送请求 def get_page(url): response = requests.get(url) return response # 2、开始解析 # 解析主页 def parse_index(data): soup = BeautifulSoup(data, 'lxml') # 获取所有app的li标签 app_list = soup.find_all(name='li', attrs={"class": "card"}) for app in app_list: # print('tank *' * 1000) # print(app) # 图标地址 img = app.find(name='img').attrs['data-original'] print(img) # 下载次数 down_num = app.find(name='span', attrs={"class": "install-count"}).text print(down_num) import re # 大小 size = soup.find(name='span', text=re.compile("\d+MB")).text print(size) # 详情页地址 detail_url = soup.find(name='a', attrs={"class": "detail-check-btn"}).attrs['href'] print(detail_url) def main(): for line in range(1, 33): url = f"https://www.wandoujia.com/wdjweb/api/category/more?catId=6001&subCatId=0&page={line}&ctoken=FRsWKgWBqMBZLdxLaK4iem9B" # 1、往app接口发送请求 response = get_page(url) # print(response.text) print('*' * 1000) # 反序列化为字典 data = response.json() # 获取接口中app标签数据 app_li = data['data']['content'] # print(app_li) # 2、解析app标签数据 parse_index(app_li) if __name__ == '__main__': main()
''' 主页: 图标地址、下载次数、大小、详情页地址 详情页: 游戏名、好评率、评论数、小编点评、下载地址、简介、网友评论、1-5张截图链接地址、 https://www.wandoujia.com/wdjweb/api/category/more?catId=6001&subCatId=0&page=1&ctoken=FRsWKgWBqMBZLdxLaK4iem9B https://www.wandoujia.com/wdjweb/api/category/more?catId=6001&subCatId=0&page=2&ctoken=FRsWKgWBqMBZLdxLaK4iem9B https://www.wandoujia.com/wdjweb/api/category/more?catId=6001&subCatId=0&page=3&ctoken=FRsWKgWBqMBZLdxLaK4iem9B 32 ''' import requests from bs4 import BeautifulSoup # 1、发送请求 def get_page(url): response = requests.get(url) return response # 2、开始解析 # 解析详情页 def parse_detail(text): soup = BeautifulSoup(text, 'lxml') # print(soup) # app名称 name = soup.find(name="span", attrs={"class": "title"}).text # print(name) # 好评率 love = soup.find(name='span', attrs={"class": "love"}).text # print(love) # 评论数 commit_num = soup.find(name='a', attrs={"class": "comment-open"}).text # print(commit_num) # 小编点评 commit_content = soup.find(name='div', attrs={"class": "con"}).text # print(commit_content) # app下载链接 download_url = soup.find(name='a', attrs={"class": "normal-dl-btn"}).attrs['href'] # print(download_url) print( f''' ============= tank ============== app名称:{name} 好评率: {love} 评论数: {commit_num} 小编点评: {commit_content} app下载链接: {download_url} ============= end ============== ''' ) # 解析主页 def parse_index(data): soup = BeautifulSoup(data, 'lxml') # 获取所有app的li标签 app_list = soup.find_all(name='li', attrs={"class": "card"}) for app in app_list: # print(app) # print('tank' * 1000) # print('tank *' * 1000) # print(app) # 图标地址 # 获取第一个img标签中的data-original属性 img = app.find(name='img').attrs['data-original'] print(img) # 下载次数 # 获取class为install-count的span标签中的文本 down_num = app.find(name='span', attrs={"class": "install-count"}).text print(down_num) import re # 大小 # 根据文本正则获取到文本中包含 数字 + MB(\d+代表数字)的span标签中的文本 size = soup.find(name='span', text=re.compile("\d+MB")).text print(size) # 详情页地址 # 获取class为detail-check-btn的a标签中的href属性 # detail_url = soup.find(name='a', attrs={"class": "name"}).attrs['href'] # print(detail_url) # 详情页地址 detail_url = app.find(name='a').attrs['href'] print(detail_url) # 3、往app详情页发送请求 response = get_page(detail_url) # 4、解析app详情页 parse_detail(response.text) def main(): for line in range(1, 33): url = f"https://www.wandoujia.com/wdjweb/api/category/more?catId=6001&subCatId=0&page={line}&ctoken=FRsWKgWBqMBZLdxLaK4iem9B" # 1、往app接口发送请求 response = get_page(url) # print(response.text) print('*' * 1000) # 反序列化为字典 data = response.json() # 获取接口中app标签数据 app_li = data['data']['content'] # print(app_li) # 2、解析app标签数据 parse_index(app_li) if __name__ == '__main__': main()
5.mongoDB的简单使用:
MongoDB 非关系型数据库
一 安装与使用
1、下载安装
https://www.mongodb.com/download-center/community
2、在C盘创建一个data/db文件夹
- 数据的存放路径
3、mongod启动服务
进入终端,输入mongod启动mongoDB服务。
4、mongo进入mongoDB客户端
打开一个新的终端,输入mongo进入客户端
二 数据库操作
数据库操作:
切换库:
SQL:
use admin; 有则切换,无则报错。
MongoDB:
use tank; 有则切换,无则创建,并切换tank库中。
查数据库:
SQL:
show databases;
MongoDB:
show dbs;
显示的数据库若无数据,则不显示。
删除库:
SQL:
drop database
MongoDB:
db.dropDatabase()
集合操作: MySQL中叫做表。
创建集合:
SQL:
create table f1, f2...
MongoDB:
# 在当前库中通过.来创建集合
db.student
插入数据:
# 插入多条数据
db.student.insert([{"name1": "tank1"}, {"name2": "tank2"}])
# 插入一条
db.student.insert({"name": "tank"})
查数据:
# 查找student集合中所有数据
db.student.find({})
# 查一条 查找name为tank的记录
db.student.find({"name":"tank"})
三 python链接MongoDB
1、下载第三方模块pymongo
pip3 install pymongo
2、链接mongoDB客户端
client = MongoClient('localhost', 27017)
6.pymongo简单使用:
from pymongo import MongoClient # 1、链接mongoDB客户端 # 参数1: mongoDB的ip地址 # 参数2: mongoDB的端口号 默认:27017 client = MongoClient('localhost', 27017) # print(client) # 2、进入tank_db库,没有则创建 # print(client['tank_db']) # 3、创建集合 # print(client['tank_db']['people']) # 4、给tank_db库插入数据 # 1.插入一条 data1 = { 'name': 'tank', 'age': 18, 'sex': 'male' } client['tank_db']['people'].insert(data1) # 2.插入多条 data1 = { 'name': 'tank', 'age': 18, 'sex': 'male' } data2 = { 'name': '戚志云', 'age': 84, 'sex': 'female' } data3 = { 'name': '沈金金', 'age': 73, 'sex': 'male' } client['tank_db']['people'].insert([data1, data2, data3]) # # # 5、查数据 # # 查看所有数据 data_s = client['tank_db']['people'].find() print(data_s) # <pymongo.cursor.Cursor object at 0x000002EEA6720128> # # 需要循环打印所有数据 for data in data_s: print(data) # # 查看一条数据 data = client['tank_db']['people'].find_one() print(data) # 官方推荐使用 # 插入一条insert_one client['tank_db']['people'].insert_one() # 插入多条insert_many client['tank_db']['people'].insert_many()
二.作业:
1、整理课堂内容,并写博客
2、基于豌豆荚爬取剩下的简介截图图片地址、网友评论
3、把豌豆荚爬取的数据插入mongoDB中
- 创建一个wandoujia库
- 把主页的数据存放一个名为index集合中
- 把详情页的数据存放一个名为detail集合中
''' 主页: 图标地址、下载次数、大小、详情页地址 详情页: 游戏名、好评率、评论数、小编点评、下载地址、简介、网友评论、1-5张截图链接地址、 https://www.wandoujia.com/wdjweb/api/category/more?catId=6001&subCatId=0&page=1&ctoken=FRsWKgWBqMBZLdxLaK4iem9B https://www.wandoujia.com/wdjweb/api/category/more?catId=6001&subCatId=0&page=2&ctoken=FRsWKgWBqMBZLdxLaK4iem9B https://www.wandoujia.com/wdjweb/api/category/more?catId=6001&subCatId=0&page=3&ctoken=FRsWKgWBqMBZLdxLaK4iem9B 32 ''' import requests from bs4 import BeautifulSoup from pymongo import MongoClient ''' 3、把豌豆荚爬取的数据插入mongoDB中 - 创建一个wandoujia库 - 把主页的数据存放一个名为index集合中 - 把详情页的数据存放一个名为detail集合中 ''' # 连接MongoDB客户端 client = MongoClient('localhost', 27017) # 创建或选择wandoujia库,index集合 index_col = client['wandoujia']['index'] # 创建或选择wandoujia库,detail集合 detail_col = client['wandoujia']['detail'] # 1、发送请求 def get_page(url): response = requests.get(url) return response # 2、开始解析 # 解析详情页 def parse_detail(text): soup = BeautifulSoup(text, 'lxml') # print(soup) # app名称 try: name = soup.find(name="span", attrs={"class": "title"}).text except Exception: # 若有异常,设置为None name = None # print(name) # 好评率 try: love = soup.find(name='span', attrs={"class": "love"}).text except Exception: love = None # print(love) # 评论数 try: commit_num = soup.find(name='a', attrs={"class": "comment-open"}).text except Exception: commit_num = None # print(commit_num) # 小编点评 try: commit_content = soup.find(name='div', attrs={"class": "con"}).text except Exception: commit_content = None # print(commit_content) # app下载链接 try: download_url = soup.find(name='a', attrs={"class": "normal-dl-btn"}).attrs['href'] except Exception: # 若有异常,设置为None download_url = None # print(download_url) # print( # f''' # ============= tank ============== # app名称:{name} # 好评率: {love} # 评论数: {commit_num} # 小编点评: {commit_content} # app下载链接: {download_url} # ============= end ============== # ''' # ) # 判断所有数据都存在,正常赋值 if name and love and commit_num and commit_content and download_url : detail_data = { 'name': name, 'love': love, 'commit_num': commit_num, 'commit_content': commit_content, 'download_url': download_url } # 若love没有值,则设置为 没人点赞,很惨 if not love: detail_data = { 'name': name, 'love': "没人点赞,很惨", 'commit_num': commit_num, 'commit_content': commit_content, 'download_url': download_url } # 若download_url没有值,则设置为 没有安装包 if not download_url: detail_data = { 'name': name, 'love': love, 'commit_num': commit_num, 'commit_content': commit_content, 'download_url': '没有安装包' } # 插入详情页数据 detail_col.insert(detail_data) print(f'{name}app数据插入成功!') # 解析主页 def parse_index(data): soup = BeautifulSoup(data, 'lxml') # 获取所有app的li标签 app_list = soup.find_all(name='li', attrs={"class": "card"}) for app in app_list: # print(app) # print('tank' * 1000) # print('tank *' * 1000) # print(app) # 图标地址 # 获取第一个img标签中的data-original属性 img = app.find(name='img').attrs['data-original'] # print(img) # 下载次数 # 获取class为install-count的span标签中的文本 down_num = app.find(name='span', attrs={"class": "install-count"}).text # print(down_num) import re # 大小 # 根据文本正则获取到文本中包含 数字 + MB(\d+代表数字)的span标签中的文本 size = soup.find(name='span', text=re.compile("\d+MB")).text # print(size) # 详情页地址 # 获取class为detail-check-btn的a标签中的href属性 # detail_url = soup.find(name='a', attrs={"class": "name"}).attrs['href'] # print(detail_url) # 详情页地址 detail_url = app.find(name='a').attrs['href'] # print(detail_url) # 拼接数据 index_data = { 'img': img, 'down_num': down_num, 'size': size, 'detail_url': detail_url } # 插入数据 index_col.insert(index_data) print('主页数据插入成功!') # 3、往app详情页发送请求 response = get_page(detail_url) # 4、解析app详情页 parse_detail(response.text) def main(): for line in range(1, 33): url = f"https://www.wandoujia.com/wdjweb/api/category/more?catId=6001&subCatId=0&page={line}&ctoken=FRsWKgWBqMBZLdxLaK4iem9B" # 1、往app接口发送请求 response = get_page(url) # print(response.text) print('*' * 1000) # 反序列化为字典 data = response.json() # 获取接口中app标签数据 app_li = data['data']['content'] # print(app_li) # 2、解析app标签数据 parse_index(app_li) # 执行完所有函数关闭mongoDB客户端 client.close() if __name__ == '__main__': main()