python学习笔记之paramiko和sqlalchemy (第九天）

参考银角大王 ：http://www.cnblogs.com/wupeiqi/articles/5095821.html

                      http://www.cnblogs.com/wupeiqi/articles/5713330.html（pymysql模块）

      金角大王：http://www.cnblogs.com/alex3714/articles/5950372.html（python mysql）

                     

                     http://www.cnblogs.com/alex3714/articles/5978329.html（sqlalchemy ORM）

 

一、Python的paramiko模块，该模块机遇SSH用于连接远程服务器并执行相关操作

1、SSHClient

用于连接远程服务器并执行基本命令

基于用户名密码连接：

import paramiko

ssh = paramiko.SSHClient()
# 允许连接不在know_hosts文件中的主机
ssh.set_missing_host_key_policy(paramiko.AutoAddPolicy())

ssh.connect(hostname='192.168.4.*',port=22,username='ubuntu',password='******')

stdin,stdout,stderr = ssh.exec_command('df -Th')

for result in stdout.readlines():
#result = list(filter(lambda x:x is not None,[stdout.read(),stderr.read()]))[0]
   print(result,end='')

ssh.close()

transport = paramiko.Transport('192.168.4.*',22)
transport.connect(username='ubuntu',password='*******')


ssh1 = paramiko.SSHClient()
ssh1._transport = transport
stdin,stdout,stderr = ssh1.exec_command('ls -l')

#result1 = list(filter(lambda x:x is not None,[stdout.read(),stderr.read()]))

for result1 in stdout.readlines():
#result = list(filter(lambda x:x is not None,[stdout.read(),stderr.read()]))[0]
   print(result1,end='')

transport.close

基于密钥连接：

import paramiko

private_key = paramiko.RSAKey.from_private_key_file('/home/ubuntu/.ssh/id_rsa')

ssh = paramiko.SSHClient()

ssh.set_missing_host_key_policy(paramiko.AutoAddPolicy())

ssh.connect(hostname='192.168.4.*',port=22,username='ubuntu',pkey=private_key)

stdin,stdout,stderr = ssh.exec_command('df -Th')


result = list(filter(lambda x:x is not None,[stdout.read(),stderr.read()]))[0]
print(result)

ssh.close()

transport = paramiko.Transport('192.168.4.*',22)
transport.connect(username='ubuntu',pkey=private_key)


ssh1 = paramiko.SSHClient()
ssh1._transport = transport
stdin,stdout,stderr = ssh1.exec_command('ls -l')

result1 = list(filter(lambda x:x is not None,[stdout.read(),stderr.read()]))

print(result1)
transport.close

基于密钥字符串：

import paramiko
from io import StringIO

private_str = """-----BEGIN RSA PRIVATE KEY-----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-----END RSA PRIVATE KEY-----""" 

private_key = paramiko.RSAKey(file_obj=StringIO(private_str))

ssh = paramiko.SSHClient()

ssh.set_missing_host_key_policy(paramiko.AutoAddPolicy())

ssh.connect(hostname='192.168.4.*',port=22,username='ubuntu',pkey=private_key)

stdin,stdout,stderr = ssh.exec_command('df -Th')


result = list(filter(lambda x:x is not None,[stdout.read(),stderr.read()]))[0]
print(result)

ssh.close()

transport = paramiko.Transport('192.168.4.*',22)
transport.connect(username='ubuntu',pkey=private_key)


ssh1 = paramiko.SSHClient()
ssh1._transport = transport
stdin,stdout,stderr = ssh1.exec_command('ls -l')

result1 = list(filter(lambda x:x is not None,[stdout.read(),stderr.read()]))

print(result1)
transport.close

 

2、SFTPClient

用于连接远程服务器并执行上传下载

可单个文件上传、下载，亦可批量上传，下载（但无法保持目录结构）

import paramiko,os,sys
from stat import ST_MODE, S_ISREG, S_ISDIR, S_ISLNK

# 定义一个类，表示一台远端linux主机
class Linux(object):
    # 通过IP, 用户名，密码，超时时间初始化一个远程Linux主机
    def __init__(self, ip, username, password, timeout=30):
        self.ip = ip
        self.username = username
        self.password = password
        self.timeout = timeout
        # transport和chanel
        self.t = ''
        self.chan = ''
        # 链接失败的重试次数
        self.try_times = 3

    # 调用该方法连接远程主机
    def connect(self):
         pass

    # 断开连接
    def close(self):
        pass

    # 发送要执行的命令
    def send(self, cmd):
        pass

    # get单个文件
    def sftp_get(self, remotefile, localfile):
        t = paramiko.Transport(sock=(self.ip, 22))
        t.connect(username=self.username, password=self.password)
        sftp = paramiko.SFTPClient.from_transport(t)
        sftp.get(remotefile, localfile)
        t.close()

    # put单个文件
    def sftp_put(self, localfile, remotefile):
        t = paramiko.Transport(sock=(self.ip, 22))
        t.connect(username=self.username, password=self.password)
        sftp = paramiko.SFTPClient.from_transport(t)
        sftp.put(localfile, remotefile)
        t.close()

    # ------获取远端linux主机上指定目录及其子目录下的所有文件------
    def __get_all_files_in_remote_dir(self, sftp, remote_dir):
        # 保存所有文件的列表
        all_files = list()

        # 去掉路径字符串最后的字符'/'，如果有的话
        if remote_dir[-1] == '/':
            remote_dir = remote_dir[0:-1]

        # 获取当前指定目录下的所有目录及文件，包含属性值
        files = sftp.listdir_attr(remote_dir)
        for x in files:
            # remote_dir目录中每一个文件或目录的完整路径
            print(x)
            print(x.st_mode)
            filename = remote_dir + '/' + x.filename
            # 如果是目录，则递归处理该目录，这里用到了stat库中的S_ISDIR方法，与linux中的宏的名字完全一致
            if S_ISDIR(x.st_mode):
                all_files.extend(self.__get_all_files_in_remote_dir(sftp, filename))
            else:
                all_files.append(filename)
        return all_files

    def sftp_get_dir(self, remote_dir, local_dir):
        t = paramiko.Transport(sock=(self.ip, 22))
        t.connect(username=self.username, password=self.password)
        sftp = paramiko.SFTPClient.from_transport(t)
    
        # 获取远端linux主机上指定目录及其子目录下的所有文件
        all_files = self.__get_all_files_in_remote_dir(sftp, remote_dir)
        # 依次get每一个文件
        for x in all_files:
            filename = x.split('/')[-1]
            local_filename = os.path.join(local_dir, filename)
            print('Get文件%s传输中...' % filename)
            sftp.get(x, local_filename)


 # ------获取本地指定目录及其子目录下的所有文件------
    def __get_all_files_in_local_dir(self, local_dir):
        # 保存所有文件的列表
        all_files = list()

        # 获取当前指定目录下的所有目录及文件，包含属性值
        files = os.listdir(local_dir)
        for x in files:
            # local_dir目录中每一个文件或目录的完整路径
            filename = os.path.join(local_dir, x)
            # 如果是目录，则递归处理该目录
            if os.path.isdir(x):
                all_files.extend(self.__get_all_files_in_local_dir(filename))
            else:
                all_files.append(filename)
        return all_files

    def sftp_put_dir(self, local_dir, remote_dir):
        t = paramiko.Transport(sock=(self.ip, 22))
        t.connect(username=self.username, password=self.password)
        sftp = paramiko.SFTPClient.from_transport(t)

        # 去掉路径字符穿最后的字符'/'，如果有的话
        if remote_dir[-1] == '/':
            remote_dir = remote_dir[0:-1]

        # 获取本地指定目录及其子目录下的所有文件
        all_files = self.__get_all_files_in_local_dir(local_dir)
        # 依次put每一个文件
        for x in all_files:
            filename = os.path.split(x)[-1]
            remote_filename = remote_dir + '/' + filename
            print('Put文件%s传输中...' % filename)
            sftp.put(x, remote_filename)


if __name__ == '__main__':
    remotefile = '/home/ubuntu/devops/currency_rate.sh' 
    localfile = '/home/ubuntu/test/currency_rate.sh' 

    remote_path = '/home/ubuntu/aa' 
    local_path = '/home/ubuntu/test' 

    host = Linux('192.168.4.*', 'ubuntu', '******')

    # 将远端的xxoo.txt get到本地，并保存为ooxx.txt
    #host.sftp_get(remotefile, localfile)

    # # 将本地的xxoo.txt put到远端，并保持为xxoo.txt
    # host.sftp_put(localfile, remotefile)


    # 将远端remote_path目录中的所有文件get到本地local_path目录
    host.sftp_get_dir(remote_path, local_path)
    # # 将本地local_path目录中的所有文件put到远端remote_path目录
    #host.sftp_put_dir(remote_path, local_path)

 

二、使用pymysql模块进行mysql数据库操作：

import pymysql

conn = pymysql.connect(host='192.168.4.*',port=3306,
                       user='hzfdt', passwd='****', db='test')
cur = conn.cursor()
cur.execute("USE test")

#cur.execute("insert into students(name,sex,age,tel) values('kai','feman',36,'18069859005')")
#conn.commit()

cur.execute("select * from students")

#cur.scroll(-1,mode='relative')

#cur.scroll(2,mode='absolute')

aa = cur.fetchall()


cur.close()
conn.close()

三、sqlalchemy使用
1、导入指定模块：

import sqlalchemy

from sqlalchemy import create_engine,Column,Integer,String,func
from sqlalchemy.ext.declarative import declarative_base
from sqlalchemy.orm import sessionmaker

2、初始化数据库连接：
###初始化数据库连接:
###'数据库类型+数据库驱动名称://用户名:口令@机器地址:端口号/数据库名'
engine = create_engine("mysql+pymysql://hzfdt:*****@192.168.4.208/test",encoding='utf-8',echo=False)

###生成orm基类
Base = declarative_base()

3、创建一个表：
###具体每个表的class定义
class User(Base):
    __tablename__ = 'user'
    id = Column(Integer, primary_key=True,autoincrement=True)
    name = Column(String(32),unique=True,nullable=False)
    password = Column(String(64),nullable=False)

    ###正常返回查询的内存对象对址，要变的可读，只需在定义表的类下面加上这样的代码
    def __repr__(self):
        return "<User(id = %d,name = %s,password = %s)>" % (self.id,self.name,self.password)

#######################创建表#######################
Base.metadata.create_all(engine)

4、添加数据：

###创建与数据库的会话session class ,注意,这里返回给session的是个class,不是实例
Session_class = sessionmaker(bind=engine)

###生成session实例
Session = Session_class()

#######################添加数据#######################
user_obj = User(name='zhang',password='123')

###把要创建的数据对象添加到这个session里
Session.add(user_obj)

###提交，创建数据
Session.commit()

5、查询数据

#######################查询数据#######################
###all返回是一个查询数据的列表，故需要循环
my_user = Session.query(User).filter_by(name = "zhang").all()

###first返回
my_user_1 = Session.query(User).filter_by(name = "zhang").first()


###one查询只有唯一一条的记录
my_user_2 = Session.query(User).filter_by(name = "kai").one()

'''
###表类中没有__repr__函数下的输出查询结果
print(my_user)
for user in my_user:
    print(user.id,user.name,user.password)

print(my_user_1)
print(my_user_1.id,my_user_1.name,my_user_1.password)

print(my_user_2)
print(my_user_2.id,my_user_2.name,my_user_2.password)
'''

###输出结果如下###
'''
[<__main__.User object at 0x103803eb8>, <__main__.User object at 0x103803f28>, <__main__.User object at 0x103803f98>]
5 zhang 123
6 zhang 123
7 zhang 123
<__main__.User object at 0x103803eb8>
5 zhang 123
<__main__.User object at 0x10390d400>
4 kai 123
'''

'''
###表类中有__repr__函数下的输出查询结果
print(my_user)
print(my_user_1)
print(my_user_2)

###输出结果如下###

[<User(id = 5,name = zhang,password = 123)>, <User(id = 6,name = zhang,password = 123)>, <User(id = 7,name = zhang,password = 123)>]
<User(id = 5,name = zhang,password = 123)>
<User(id = 4,name = kai,password = 123)>
'''

   6、修改数据：

#######################修改数据#######################
my_user = Session.query(User).filter_by(name = "zhang").first()

print(my_user)

my_user.password = '123456'

Session.commit()

print(my_user)

  7、回滚数据：

#######################回滚数据######################
my_user = Session.query(User).filter_by(name = 'wang').first()

my_user.name = 'zhou'

fake_user = User(name = 'liu',password = 'abcd')
Session.add(fake_user)
###这时看session里有你刚添加和修改的数据
print(Session.query(User).filter(User.name.in_(['zhou','liu'])).all() )

#Session.rollback()

print(Session.query(User).filter(User.name.in_(['zhou','liu'])).all() )

Session.commit()

   8、外键关联：

relationship进行二表关联，名字随便取

relationship_populates二个表中的populates后面的命名必须互为对应

relationship_backref 在关联表中定义，允许你在被关联表里通过backref字段反向查出所有它在本表里的关联项

#!/Library/Frameworks/Python.framework/Versions/3.6/bin/python3
# -*- coding: utf-8 -*-

import sqlalchemy
from sqlalchemy import create_engine,Column,Integer,String,func,ForeignKey,and_
from sqlalchemy.ext.declarative import declarative_base
from sqlalchemy.orm import sessionmaker,relationship

###初始化数据库连接:
###'数据库类型+数据库驱动名称://用户名:口令@机器地址:端口号/数据库名'
engine = create_engine("mysql+pymysql://hzfdt:******@192.168.4.208/test",encoding='utf-8',echo=False)

###生成orm基类
Base = declarative_base()

###具体每个表的class定义
class User(Base):
    __tablename__ = 'user'
    id = Column(Integer, primary_key=True,autoincrement=True)
    name = Column(String(32),unique=True,nullable=False)
    password = Column(String(64),nullable=False)

    #user_rs = relationship("Address")
    #user_list = relationship("Address",back_populates='addr')
    user_rs_backref = relationship("Address",backref="user_list_1")
    ###这个nb，允许你在user表里通过backref字段反向查出所有它在addresses表里的关联项

    ###正常返回查询的内存对象对址，要变的可读，只需在定义表的类下面加上这样的代码
    #def __repr__(self):
    #   return "<User(id = %d,name = %s,password = %s)>" % (self.id,self.name,self.password)

class Address(Base):
    __tablename__ = 'addresses'
    id = Column(Integer, primary_key=True, autoincrement=True)
    email_address = Column(String(32), nullable=False)
    user_id = Column(Integer, ForeignKey('user.id'))

    #addr_rs = relationship("User")
    #addr = relationship("User",back_populates="user_list")
    addr_rs_backref = relationship("User",backref="addr_1")

    #def __repr__(self):
    #   return "<Address(email_address='%s')>" % self.email_address


#######################创建表#######################
#Base.metadata.create_all(engine)

###创建与数据库的会话session class ,注意,这里返回给session的是个class,不是实例
Session_class = sessionmaker(bind=engine)

###生成session实例
Session = Session_class()




#obj = Session.query(User).filter(and_(User.name=='zhang',User.id=='6')).first()
#obj = Session.query(User).filter(User.name=='zhang',User.id=='6').first()
#print(obj.name,obj.id)
'''
obj.addresses = [Address(email_address='aa@hzfdt.com'),
                 Address(email_address='bb@hzfdt.com')]

Session.commit()
print(obj.addresses)
'''

user_obj = Session.query(User).filter(User.name=='zhang').first()
addr_obj = Session.query(Address).first()

#########relationship################
###用relationship进行二表关联，名字随便取###
#print(user_obj.name,user_obj.password)
#for i in user_obj.user_rs:
#    print(i.user_id,i.email_address)
#print(addr_obj.addr_rs.name,addr_obj.addr_rs.id)
'''
结果如下：
zhang 123456
5 aa@qq.com
5 bb@qq.com
zhang 5
'''
#########relationship_populates################
###二个表中的populates后面的命名必须互为对应###
#print(user_obj.name,user_obj.password)
#for i in user_obj.user_list:
#    print(i.user_id,i.email_address)
#print(addr_obj.addr.name,addr_obj.addr.id)

'''
结果如下：
zhang 123456
5 aa@qq.com
5 bb@qq.com
zhang 5
'''

#############relationship_backref###############
####这个nb，允许你在user表里通过backref字段反向查出所有它在addresses表里的关联项
print(user_obj.name,user_obj.password)
for i in user_obj.addr_1:
    print(i.email_address)
print(addr_obj.user_list_1.name,addr_obj.user_list_1.id)

'''
结果如下：
zhang 123456
aa@qq.com
bb@qq.com
zhang 5
'''

 

9、多对多关系

处理中文

sqlalchemy设置编码字符集一定要在数据库访问的URL上增加charset=utf8，否则数据库的连接就不是utf8的编码格式

eng = create_engine('mysql://root:root@localhost:3306/test2?charset=utf8',echo=True)

#一本书可以有多个作者，一个作者又可以出版多本书

from sqlalchemy.ext.declarative import declarative_base
from sqlalchemy import Column, Integer, String, ForeignKey, UniqueConstraint, Index,func,and_,Table,text,DATE
from sqlalchemy.orm import sessionmaker, relationship
from sqlalchemy import create_engine
from sqlalchemy.sql import func


engine = create_engine("mysql+pymysql://hzfdt:*****@192.168.4.x/test?charset=utf8",echo=True)

###生成orm基类
Base = declarative_base()

book_m2m_author = Table('book_m2m_author', Base.metadata,
                        Column('book_id',Integer,ForeignKey('books.id')),
                        Column('author_id',Integer,ForeignKey('authors.id')),
                        )

class Book(Base):
    __tablename__ = 'books'
    id = Column(Integer,primary_key=True)
    name = Column(String(256))
    pub_date = Column(DATE)
    authors = relationship('Author',secondary=book_m2m_author,backref='books')


    def __repr__(self):
       return "the book name is %s,the pub date is %s" % (self.name,self.pub_date)

class Author(Base):
    __tablename__ = 'authors'
    id = Column(Integer, primary_key=True)
    name = Column(String(256))

    #abc = relationship('Book', secondary=book_m2m_author, backref='auth')

    def __repr__(self):
        return "the author name is %s" % self.name

#Base.metadata.create_all(engine)
###创建与数据库的会话session class ,注意,这里返回给session的是个class,不是实例
Session_class = sessionmaker(bind=engine)
s = Session_class()

###添加数据###
'''
b1 = Book(name="跟Alex学Python")
b2 = Book(name="跟Alex学把妹")
b3 = Book(name="跟Alex学装逼")
b4 = Book(name="跟Alex学开车")

a1 = Author(name="Alex")
a2 = Author(name="Jack")
a3 = Author(name="Rain")

b1.authors = [a1, a2]
b2.authors = [a1, a2, a3]

s.add_all([b1, b2, b3, b4, a1, a2, a3])

s.commit()
'''

###查询数据###
print('--------通过书表查关联的作者---------')
 
book_obj = s.query(Book).filter_by(name="跟Alex学Python").first()
print(book_obj.name, book_obj.authors)
 
print('--------通过作者表查关联的书---------')
author_obj =s.query(Author).filter_by(name="Alex").first()
print(author_obj.name , author_obj.books)

###多对多删除###
###删除数据时不用管boo_m2m_authors , sqlalchemy会自动帮你把对应的数据删除###

#通过书删除作者
author_obj =s.query(Author).filter_by(name="Jack").first()
book_obj = s.query(Book).filter_by(name="跟Alex学把妹").first()
book_obj.authors.remove(author_obj) #从一本书里删除一个作者

#通过作者删除书#
book_obj = s.query(Book).filter_by(name="跟Alex学Python").first()
author_obj.books.remove(book_obj)  #从一个作者里删除一本书
s.commit()


#直接删除作者或书#
author_obj =s.query(Author).filter_by(name="Alex").first()
book_obj = s.query(Book).filter_by(name="跟Alex学把妹").first()
s.delete(author_obj)
s.delete(book_obj)
s.commit()

 

10、使用sqlalchemy建立携带加密字段的ORM表

数据库密码明文是很危险的一件事情，所以需要进行对密码进行加密。结werkzeug.security进行对用户密码加密。

from sqlalchemy.ext.hybrid import hybrid_property
from werkzeug.security import generate_password_hash,check_password_hash

class UserProfile(Base):
    __tablename__ = 'user_profile'
    id = Column(Integer,primary_key=True,autoincrement=True)
    username = Column(String(32),unique=True,nullable=False)
    password = Column(String(256),unique=True,nullable=False)
    groups = relationship('Group',secondary=Group2UserProfile)
    bind_hosts = relationship('BindHost',secondary=BindHost2UserProfile)
    audit_logs = relationship('AuditLog')


    @hybrid_property
    def passwd(self):
        return self.password

    @passwd.setter
    def hash_passwd(self,plaintext):
        self.password = generate_password_hash(plaintext)

    def verify_passwd(self,plaintext):
        return check_password_hash(self.password,plaintext)

#创建的时候还是使用password字段存入

obj = models.UserProfile(username=key,passwd=val.get('password'))

 #直接使用方法，密码正确就会返回True

user_obj = session.query(models.UserProfile).filter(models.UserProfile.username==username).first()

user_obj.verify_passwd(password)

故障排错：

在python3.4下SQLAlchemy1.1.18下如下设置：

@hybrid_property
def passwd(self):
      return self.password

@passwd.setter
def hash_passwd(self,plaintext):
     self.password = generate_password_hash(plaintext)

二个函数名可以不一致；但在python3.5下SQLAlchemy1.2.6环境下，函数名称一定要一样，否则会报如下错误：

File "/usr/local/lib/python3.5/dist-packages/SQLAlchemy-1.2.6-py3.5-linux-x86_64.egg/sqlalchemy/ext/hybrid.py", line 873, in __set__
raise AttributeError("can't set attribute")
AttributeError: can't set attribute