ORM框架Peewee(高级连接）peewee连接池、主从、重连、ssh连接

一、peewee连接池

 from peewee import *
 from playhouse.pool import PooledMySQLDatabase, PooledDatabase

  PooledMySQLDatabase(
     'peewee_test',
     max_connections=8,
     stale_timeout=300,
     user='user', 
     password='password',
     host='127.0.0.0',
     port=3306
    )

二、Peewee主从式 pip install pwmd

#!/usr/bin/python
# -*- coding: utf-8 -*-
import unittest
from datetime import date

from peewee import Model, CharField, DateField, BooleanField
from pwmd import MultiMySQLDatabase

DATABASE = {'master': 'mysql://root@localhost/test_app',
            'slaves': ['mysql://root@localhost/test_app']}
db = MultiMySQLDatabase(DATABASE)
db.connect()


class BaseModel(Model):
    class Meta:
        database = db


class Person(BaseModel):
    name = CharField()
    birthday = DateField()
    is_relative = BooleanField()


class TestMulti(unittest.TestCase):

    def setUp(self):
        Person.create_table()

    def test_person(self):
        uncle_bob = Person(name='Bob', birthday=date(1960, 1, 15), is_relative=True)
        uncle_bob.save()
        Person.get(Person.name == 'Bob') == uncle_bob

    def tearDown(self):
        Person.drop_table()
        

三、 peewee 数据库重连，连接池连接不够

# _*_ coding:utf-8 _*_
from playhouse.pool import PooledMySQLDatabase
from playhouse.shortcuts import ReconnectMixin
import config
 
class RetryMySQLDatabase(ReconnectMixin, PooledMySQLDatabase):
    _instance = None
 
    @staticmethod
    def get_db_instance():
        if not RetryMySQLDatabase._instance:
            RetryMySQLDatabase._instance = RetryMySQLDatabase(
                    config.get('db_name', 'aaabb'),
                    max_connections=8,
                    stale_timeout=300,
                    host=config.get('db_host', '127.0.0.1'),
                    user=config.get('db_user', 'root'),
                    password=config.get('db_pwd', '123'),
                    port=config.get('db_port', 3306)
                    )
        return RetryMySQLDatabase._instance
 
 
# 如何使用？
# 在model文件中
database = RetryMySQLDatabase.get_db_instance()



为了不用不停的连接断开peewee提供with 操作

with database.connection_context():
    Person.select()
    ....


转载 https://blog.csdn.net/max229max/article/details/90512313

三、ssh访问数据库的实例

• 方法一

  from peewee import *
  from playhouse.db_url import connect
  from sshtunnel import SSHTunnelForwarder
  
  server = SSHTunnelForwarder(
    (sshServerB_ip, sshServerB_port), # 跳板机配置
    ssh_password=sshServerB_pwd,
    ssh_username=sshServerB_usr,
    remote_bind_address=(databaseA_ip, databaseA_port)  # 远程的MySQL|Redis服务器
    ) 
  server.start()
  destination_lib = connect('mysql://%s:%s@127.0.0.1:%d/%s' % (databaseA_usr, databaseA_pwd, server.local_bind_port, databaseA_db))
  ''' your code to operate the databaseA '''
  server.close()
  

使用SSHTunnelForwarder隧道，通过跳板机链接MySQL

• 方法二 使用SSHTunnelForwarder隧道，通过跳板机链接Redis

1. 通过SSHTunnelForwarder，paramiko模块，先ssh到跳板机，然后在跳板机上（或者内部服务器上），获取到权限，然后远程Redis。

2. 使用SSHTunnelForwarder模块，通过本地22端口ssh到跳板机，然后本地开启一个转发端口给跳板机远程Redis服务使用。

   import sshtunnel
   with SSHTunnelForwarder(
           ('xxx.xxx.xx.xx', 22),  # 跳板机
           ssh_username=username,
           ssh_pkey="/Users/xxx/.ssh/id_rsa",
           remote_bind_address=('xx.xx.xx.xxx', 6379),  # 远程的Redis服务器
           local_bind_address=('0.0.0.0', 10022)        # 开启本地转发端口
   ) as server:
       server.start()  # 开启隧道
       print(server.local_bind_port)
       # 本地通过local_bind_port端口转发，利用跳板机，链接Redis服务
       cls.red = redis.Redis(host='127.0.0.1', port=server.local_bind_port, db=db, decode_responses=True)
       server.close()  # 关闭隧道
   

本文地址：https://blog.csdn.net/a6864657/article/details/107635043