python16_day10【SelectWeb、SelectWget、paramiko、pymysql】

一、select实现Web框架(自定义WEB框架)

　　浏览器输入：http://127.0.0.1:8888/index.html

 import select
 import socket

 class Flask(object):
     def __init__(self, routers):
         self.routers = routers

     def process_data(self, client):
         data = bytes()
         while True:
             try:
                 trunk = client.recv(1024)  # 没有数据会报错, 用户断开也会报错.
             except BlockingIOError as e:
                 trunk = ""
             if not trunk:
                 break
             data += trunk
         data_str = str(data, encoding='utf8')
         header, body = data_str.split('\r\n\r\n', 1)
         header_list = header.split('\r\n')
         header_dict = {}
         for line in header_list:
             value = line.split(":", 1)
             if len(value) == 2:
                 k, v = value
                 header_dict[k] = v
             else:
                 header_dict['mothod'], header_dict['url'], header_dict['protocol'] = line.split(' ')

         return header_dict, body

     def run(self, host='127.0.0.1', port=8888):
         sock = socket.socket()
         sock.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEADDR, 1)
         sock.setblocking(False)
         sock.bind((host, port))
         sock.listen(5)

         inputs = [sock, ]
         while True:
             rList, wList, eList = select.select(inputs, [], [], 0.5)
             for client in rList:
                 # 建立新的连接
                 if client == sock:
                     conn, addr = client.accept()
                     conn.setblocking(False)
                     inputs.append(conn)
                 else:           # 用户发送数据
                     header_dict, body = self.process_data(client)
                     request_url = header_dict['url']
                     func_name = None
                     for item in self.routers:
                         if item[0] == request_url:
                             func_name = item[1]
                             break
                     if not func_name:
                         client.sendall(b"")
                     else:
                         result = func_name(header_dict, body)
                         client.sendall(result.encode('utf8'))
                     inputs.remove(client)
                     client.close()

flask.py

 import flask

 def f1(header, body):
     return "from f1"

 def f2(header, body):
     return "from f2"

 routers = [
     ('/index.html', f1),
     ('/login.html', f2),
 ]

 obj = flask.Flask(routers)
 obj.run()

二、自定义Wget(爬虫)

　　select使用基类的fileno进行，使用foo在中间封装一层，从而增加更多的功能。

 #!/usr/bin/env python
 # -*-coding:utf8-*-
 # __author__ = "willian"
 import socket
 import select

 # 中间封装一层
 class Foo(object):
     def __init__(self, sock, callback, url, host):
         self.sock = sock
         self.callback = callback
         self.url = url
         self.host = host

     def fileno(self):
         return self.sock.fileno()

 class NbIO(object):
     def __init__(self):
         self.fds = []
         self.connections = []

     def connect(self, url_list):
         for item in url_list:
             conn = socket.socket()
             conn.setblocking(False)
             # 1. 发送链接请求
             try:
                 conn.connect((item['host'], 80))
             except BlockingIOError as e:
                 pass
             obj = Foo(conn, item['callback'], item['url'], item['host'])
             self.fds.append(obj)
             self.connections.append(obj)

     def send(self):
         while True:
             if len(self.fds) == 0:
                 break
             # wList，有对象；当前socket已经创建链接
             rList, wList, eList = select.select(self.fds, self.connections, self.fds, 0.5)

             for obj in rList:
                 # 4.有数据响应回来了
                 conn = obj.sock
                 data = bytes()
                 while True:
                     try:
                         d = conn.recv(1024)
                         data = data + d
                     except BlockingIOError as e:
                         d = None
                     if not d:
                         break
                 # print(data)
                 obj.callback(data)  # 自定义操作 f1  f2
                 self.fds.remove(obj)
                 # print(len(self.fds),len(self.connections))
                 # 执行当前请求 函数：f1  f2
             # 【1,2,3，】
             for obj in wList:
                 # 2.已经连接上远程
                 conn = obj.sock
                 # 3. 发送数据
                 # HTTP/1.1\r\nHost: %s\r\n\r\n
                 template = "GET %s HTTP/1.1\r\nHost: %s\r\n\r\n" % (obj.url, obj.host,)
                 # template = "POST %s HTTP/1.1\r\nHost: 127.0.0.1:8888\r\n\r\nk1=v1&k2=v2" %(obj.url,)
                 conn.sendall(template.encode('utf-8'))
                 self.connections.remove(obj)

基类

 import spider

 def f1(data):
     print("\033[31;1m{0}\033[0m".format(data))

 def f2(data):
     print("\033[32;1m{0}\033[0m".format(data))

 url_list = [
     {'host': "www.baidu.com", 'url': '/', 'callback': f1},   # socket
     {'host': "www.bing.com", 'url': '/', 'callback': f2},
     {'host': "www.cnblogs.com", 'url': '/wupeiqi', 'callback': f1},
     {'host': "www.oldboyedu.com", 'url': '/', 'callback': f1},
 ]
 obj = spider.NbIO()
 obj.connect(url_list)
 obj.send()

三、paramiko实现SSH登录

 #!/usr/bin/env python
 # -*-coding:utf8-*-
 # __author__ = "willian"

 import paramiko

 class SshHelper(object):
     def __init__(self, host, port, username, pwd):
         self.host = host
         self.port = port
         self.username = username
         self.pwd = pwd
         self.transport = None

     def connect(self):
         transport = paramiko.Transport((self.host, self.port,))
         transport.connect(username=self.username, password=self.pwd)
         self.transport = transport

     def put(self, local, target):
         sftp = paramiko.SFTPClient.from_transport(self.transport)
         # 将location.py 上传至服务器 /tmp/test.py
         sftp.put(local, target)

     def get(self, remote, local):
         sftp = paramiko.SFTPClient.from_transport(self.transport)
         sftp.get(remote, local)

     def cmd(self, cmd):
         ssh = paramiko.SSHClient()
         ssh._transport = self.transport
         stdin, stdout, stderr = ssh.exec_command(cmd)
         stdout.read()

     def close(self):
         self.transport.close()

 if __name__ == '__main__':
     obj = SshHelper('1.1.1.1')
     obj.connect()
     obj.close()

ssh封装类

四、MySQL

　　1.mysql认识和基本操作

　　　　http://www.cnblogs.com/wupeiqi/articles/5713315.html

　　　　http://www.cnblogs.com/wupeiqi/articles/5713323.html

 a、条件
     select * from 表 where id > 1 and name != 'alex' and num = 12;

     select * from 表 where id between 5 and 16;

     select * from 表 where id in (11,22,33)
     select * from 表 where id not in (11,22,33)
     select * from 表 where id in (select nid from 表)

 b、通配符
     select * from 表 where name like 'ale%'  - ale开头的所有（多个字符串）
     select * from 表 where name like 'ale_'  - ale开头的所有（一个字符）

 c、限制
     select * from 表 limit 5;            - 前5行
     select * from 表 limit 4,5;          - 从第4行开始的5行
     select * from 表 limit 5 offset 4    - 从第4行开始的5行

 d、排序
     select * from 表 order by 列 asc              - 根据 “列” 从小到大排列
     select * from 表 order by 列 desc             - 根据 “列” 从大到小排列
     select * from 表 order by 列1 desc,列2 asc    - 根据 “列1” 从大到小排列，如果相同则按列2从小到大排序

 e、分组
     select num from 表 group by num
     select num,nid from 表 group by num,nid
     select num,nid from 表  where nid > 10 group by num,nid order nid desc
     select num,nid,count(*),sum(score),max(score),min(score) from 表 group by num,nid

     select num from 表 group by num having max(id) > 10

     特别的：group by 必须在where之后，order by之前

 f、连表
     无对应关系则不显示
     select A.num, A.name, B.name
     from A,B
     Where A.nid = B.nid

     无对应关系则不显示
     select A.num, A.name, B.name
     from A inner join B
     on A.nid = B.nid

     A表所有显示，如果B中无对应关系，则值为null
     select A.num, A.name, B.name
     from A left join B
     on A.nid = B.nid

     B表所有显示，如果B中无对应关系，则值为null
     select A.num, A.name, B.name
     from A right join B
     on A.nid = B.nid

 g、组合
     组合，自动处理重合
     select nickname
     from A
     union
     select name
     from B

     组合，不处理重合
     select nickname
     from A
     union all
     select name
     from B

复杂查询

　　2.python操作MySQL

　　对于Python操作MySQL主要使用两种方式：

• 原生pymysql
• ORM方式sqlAlchemy

　　安装：pip3 install pymysql

 import pymysql

 # 创建连接
 conn = pymysql.connect(host='127.0.0.1', port=3306, user='root', passwd='', db='t1')
 # 创建游标
 cursor = conn.cursor()

 # 执行SQL，并返回收影响行数
 effect_row = cursor.execute("update hosts set host = '1.1.1.2'")

 # 执行SQL，并返回受影响行数
 #effect_row = cursor.execute("update hosts set host = '1.1.1.2' where nid > %s", (1,))

 # 执行SQL，并返回受影响行数
 #effect_row = cursor.executemany("insert into hosts(host,color_id)values(%s,%s)", [("1.1.1.11",1),("1.1.1.11",2)])

 # 提交，不然无法保存新建或者修改的数据
 conn.commit()

 # 关闭游标
 cursor.close()
 # 关闭连接
 conn.close()

执行SQL

 conn = pymysql.connect(host='127.0.0.1', port=3306, user='root', passwd='', db='t1')
 cursor = conn.cursor()
 cursor.executemany("insert into hosts(host,color_id)values(%s,%s)", [("1.1.1.11",1),("1.1.1.11",2)])
 conn.commit()
 cursor.close()
 conn.close()

 # 获取最新自增ID
 new_id = cursor.lastrowid

获取自增ID

 import pymysql

 conn = pymysql.connect(host='127.0.0.1', port=3306, user='root', passwd='', db='t1')
 cursor = conn.cursor()
 cursor.execute("select * from hosts")

 # 获取第一行数据
 row_1 = cursor.fetchone()

 # 获取前n行数据
 # row_2 = cursor.fetchmany(3)
 # 获取所有数据
 # row_3 = cursor.fetchall()

 conn.commit()
 cursor.close()
 conn.close()

获取数据

注：在fetch数据时按照顺序进行，可以使用cursor.scroll(num,mode)来移动游标位置，如：

• cursor.scroll(1,mode='relative')  # 相对当前位置移动
• cursor.scroll(2,mode='absolute') # 相对绝对位置移动

　　关于默认获取的数据是元祖类型，如果想要或者字典类型的数据，即：

 import pymysql

 conn = pymysql.connect(host='127.0.0.1', port=3306, user='root', passwd='', db='t1')

 # 游标设置为字典类型
 cursor = conn.cursor(cursor=pymysql.cursors.DictCursor)
 r = cursor.execute("call p1()")

 result = cursor.fetchone()

 conn.commit()
 cursor.close()
 conn.close()

获取数据类型

MySQL练习：

　　http://www.cnblogs.com/wupeiqi/articles/5729934.html

　　http://www.cnblogs.com/wupeiqi/articles/5748496.html