Django多数据库配置及逆向生成model教程

砸漏

发布于 2020-11-04 15:52:42

7470

发布于 2020-11-04 15:52:42

文章被收录于专栏：恩蓝脚本

在项目中我们每个app对应不同的数据库，其中有一个是从数据库逆向生成model，做个笔记。

1、修改项目的setting.py配置：

DATABASES = {
 'default': {
  'ENGINE': 'django.db.backends.mysql', # 默认用mysql
  'NAME': 'bk',      # 数据库名 (默认与APP_ID相同)
  'USER': 'root',      # 你的数据库user
  'PASSWORD': 'root',      # 你的数据库password
  'HOST': 'xxx.xxx.xxx.xxx',     # 开发的时候，使用localhost
  'PORT': '3306',      # 默认3306
 },
 'cloudsino_test': {
   'ENGINE': 'django.db.backends.mysql', # 默认用mysql
   'NAME': 'cloudsino_test',      # 数据库名 (默认与APP_ID相同)
   'USER': 'root',      # 你的数据库user
   'PASSWORD': 'root',      # 你的数据库password
   'HOST': 'xxx.xxx.xxx.xxx',     # 开发的时候，使用localhost
   'PORT': '3306',      # 默认3306
  },
}

# 设置数据库的路由规则方法
DATABASE_ROUTERS = ['conf.database_router.DatabaseAppsRouter']

# 设置APP对应的数据库路由表，哪个app要连接哪个数据库，没有指定会用default那个。
DATABASE_APPS_MAPPING = {
 # example:
 #'app_name':'database_name',
 'home_application': 'cloudsino_test',
 'cmdb': 'default',
}

2、新建database_router.py：

在与setting.py文件同级的目录下新建database_router.py文件：

# -*- coding: utf-8 -*-
from settings_development import DATABASE_APPS_MAPPING

DATABASE_MAPPING = DATABASE_APPS_MAPPING


class DatabaseAppsRouter(object):
 def db_for_read(self, model, **hints):
  """"建议model类型对象从哪一个数据库读取."""
  if model._meta.app_label in DATABASE_MAPPING:
   return DATABASE_MAPPING[model._meta.app_label]
  return None

 def db_for_write(self, model, **hints):
  """建议model类型对象的写入操作应该使用哪个数据库"""
  if model._meta.app_label in DATABASE_MAPPING:
   return DATABASE_MAPPING[model._meta.app_label]
  return None

 def allow_relation(self, obj1, obj2, **hints):
  """Allow any relation between apps that use the same database.
  	如果obj1 和obj2 之间应该允许关联则返回True，如果应该防止关联则返回False，如果路由无法判断则返回None
  """
  db_obj1 = DATABASE_MAPPING.get(obj1._meta.app_label)
  db_obj2 = DATABASE_MAPPING.get(obj2._meta.app_label)
  if db_obj1 and db_obj2:
   if db_obj1 == db_obj2:
    return True
   else:
    return False
  return None

 def allow_syncdb(self, db, model):
  """Make sure that apps only appear in the related database."""

  if db in DATABASE_MAPPING.values():
   return DATABASE_MAPPING.get(model._meta.app_label) == db
  elif model._meta.app_label in DATABASE_MAPPING:
   return False
  return None

 def allow_migrate(self, db, app_label, model=None, **hints):
  """
  Make sure the auth app only appears in the 'auth_db' database.
  定义迁移操作是否允许在别名为db的数据库上运行。如果操作应该运行则返回True ，如果不应该运行则返回False，如果路由无法判断则返回None。
  """
  if db in DATABASE_MAPPING.values():
   return DATABASE_MAPPING.get(app_label) == db
  elif app_label in DATABASE_MAPPING:
   return False
  return None

3.逆向生成model：

在terminal中输入以下命令，使用名为cloudsino_test的DATABASE来逆向生成model到home_application这个app的models.py：

python manage.py inspectdb –database=cloudsino_test home_application/models.py

逆向生成的model：

# This is an auto-generated Django model module.
# You'll have to do the following manually to clean this up:
# * Rearrange models' order
# * Make sure each model has one field with primary_key=True
# * Remove `managed = False` lines if you wish to allow Django to create, modify, and delete the table
# Feel free to rename the models, but don't rename db_table values or field names.
#
# Also note: You'll have to insert the output of 'django-admin sqlcustom [app_label]'
# into your database.
from __future__ import unicode_literals
from django.db import models
class CloudsinoCpuinfo(models.Model):
corenumber = models.CharField(max_length=128)
frequency = models.CharField(max_length=128)
index = models.CharField(max_length=128)
manufacturer = models.CharField(max_length=128)
name = models.CharField(max_length=128)
partnumber = models.CharField(max_length=128)
serialnumber = models.CharField(max_length=128)
type = models.CharField(max_length=128)
device = models.ForeignKey('CloudsinoDevice', blank=True, null=True)
class Meta:
managed = False
db_table = 'cloudsino_cpuinfo'
class CloudsinoDevice(models.Model):
sn = models.CharField(max_length=128)
app = models.CharField(max_length=128)
business_chargeby1 = models.CharField(max_length=128)
business_chargeby2 = models.CharField(max_length=128)
chargeby1 = models.CharField(max_length=128)
chargeby2 = models.CharField(max_length=128)
description = models.CharField(max_length=128)
device_status = models.CharField(max_length=128)
devicename = models.CharField(max_length=128)
field1 = models.CharField(max_length=128)
field2 = models.CharField(max_length=128)
field3 = models.CharField(max_length=128)
field4 = models.CharField(max_length=128)
field5 = models.CharField(max_length=128)
frame_posiniton = models.CharField(max_length=128)
framename = models.CharField(max_length=128)
ip = models.CharField(max_length=128)
manufacturer = models.CharField(max_length=128)
model = models.CharField(max_length=128)
os = models.CharField(max_length=128)
position_desc = models.CharField(max_length=128)
roomarea = models.CharField(max_length=128)
roomname = models.CharField(max_length=128)
servicetag = models.CharField(max_length=128)
shape = models.CharField(max_length=128)
specification = models.CharField(max_length=128)
subtype = models.CharField(max_length=128)
type = models.CharField(max_length=128)
ucount = models.CharField(max_length=128)
class Meta:
managed = False
db_table = 'cloudsino_device'
class CloudsinoDevicetype(models.Model):
name = models.CharField(max_length=128)
type = models.CharField(max_length=128)
status = models.CharField(max_length=128)
class Meta:
managed = False
db_table = 'cloudsino_devicetype'
class CloudsinoDiskinfo(models.Model):
bus = models.CharField(max_length=128)
formfactor = models.CharField(max_length=128)
index = models.CharField(max_length=128)
manufacturer = models.CharField(max_length=128)
media = models.CharField(max_length=128)
name = models.CharField(max_length=128)
partnumber = models.CharField(max_length=128)
serialnumber = models.CharField(max_length=128)
size = models.CharField(max_length=128)
speed = models.CharField(max_length=128)
type = models.CharField(max_length=128)
device = models.ForeignKey(CloudsinoDevice, blank=True, null=True)
class Meta:
managed = False
db_table = 'cloudsino_diskinfo'
class CloudsinoFaninfo(models.Model):
index = models.CharField(max_length=128)
name = models.CharField(max_length=128)
partnumber = models.CharField(max_length=128)
serialnumber = models.CharField(max_length=128)
device = models.ForeignKey(CloudsinoDevice, blank=True, null=True)
class Meta:
managed = False
db_table = 'cloudsino_faninfo'
class CloudsinoHbacardinfo(models.Model):
name = models.CharField(max_length=128)
wwnn = models.CharField(max_length=128)
wwpn = models.CharField(max_length=128)
fc_switch = models.CharField(max_length=128)
switch_port = models.CharField(max_length=128)
switch_mac = models.CharField(max_length=128)
device = models.ForeignKey(CloudsinoDevice, blank=True, null=True)
class Meta:
managed = False
db_table = 'cloudsino_hbacardinfo'
class CloudsinoManageinfo(models.Model):
assetcode = models.CharField(max_length=128)
department = models.CharField(max_length=128)
express_code = models.CharField(max_length=128)
service_level = models.CharField(max_length=128)
shutdown_level = models.CharField(max_length=128)
usage = models.CharField(max_length=128)
device = models.ForeignKey(CloudsinoDevice, blank=True, null=True)
class Meta:
managed = False
db_table = 'cloudsino_manageinfo'
class CloudsinoManufacturertype(models.Model):
name = models.CharField(max_length=128)
type = models.CharField(max_length=128)
status = models.CharField(max_length=128)
class Meta:
managed = False
db_table = 'cloudsino_manufacturertype'
class CloudsinoMemory(models.Model):
name = models.CharField(max_length=128)
type = models.CharField(max_length=128)
frequency = models.CharField(max_length=128)
size = models.CharField(max_length=128)
manufacturer = models.CharField(max_length=128)
partnumber = models.CharField(max_length=128)
serialnumber = models.CharField(max_length=128)
index = models.CharField(max_length=128)
memoryinfo = models.ForeignKey('CloudsinoMemoryinfo', blank=True, null=True)
class Meta:
managed = False
db_table = 'cloudsino_memory'
class CloudsinoMemoryinfo(models.Model):
max_dimmslots = models.CharField(max_length=128)
mem_totalsize = models.CharField(max_length=128)
memmax_capacitysize = models.CharField(max_length=128)
populated_dimmslots = models.CharField(max_length=128)
device = models.ForeignKey(CloudsinoDevice, blank=True, null=True)
class Meta:
managed = False
db_table = 'cloudsino_memoryinfo'
class CloudsinoNetworkinfo(models.Model):
name = models.CharField(max_length=128)
type = models.CharField(max_length=128)
mac = models.CharField(max_length=128)
speed = models.CharField(max_length=128)
manufacturer = models.CharField(max_length=128)
partnumber = models.CharField(max_length=128)
serialnumber = models.CharField(max_length=128)
index = models.CharField(max_length=128)
device = models.ForeignKey(CloudsinoDevice, blank=True, null=True)
class Meta:
managed = False
db_table = 'cloudsino_networkinfo'
class CloudsinoOobnetwork(models.Model):
ip = models.CharField(max_length=128)
netmask = models.CharField(max_length=128)
gateway = models.CharField(max_length=128)
mac = models.CharField(max_length=128)
ethernet_switch = models.CharField(max_length=128)
swith_port = models.CharField(max_length=128)
swith_mac = models.CharField(max_length=128)
distribution_frame = models.CharField(max_length=128)
distribution = models.CharField(max_length=128)
device = models.ForeignKey(CloudsinoDevice, blank=True, null=True)
class Meta:
managed = False
db_table = 'cloudsino_oobnetwork'
class CloudsinoPciecard(models.Model):
name = models.CharField(max_length=128)
type = models.CharField(max_length=128)
loc = models.CharField(max_length=128)
online_state = models.CharField(max_length=128)
conntype = models.CharField(max_length=128)
bandwidth = models.CharField(max_length=128)
speed = models.CharField(max_length=128)
manufacturer = models.CharField(max_length=128)
partnumber = models.CharField(max_length=128)
serialnumber = models.CharField(max_length=128)
index = models.CharField(max_length=128)
device = models.ForeignKey(CloudsinoDevice, blank=True, null=True)
class Meta:
managed = False
db_table = 'cloudsino_pciecard'
class CloudsinoPowerinfo(models.Model):
name = models.CharField(max_length=128)
type = models.CharField(max_length=128)
model = models.CharField(max_length=128)
outputpower = models.CharField(max_length=128)
manufacturer = models.CharField(max_length=128)
partnumber = models.CharField(max_length=128)
serialnumber = models.CharField(max_length=128)
index = models.CharField(max_length=128)
device = models.ForeignKey(CloudsinoDevice, blank=True, null=True)
class Meta:
managed = False
db_table = 'cloudsino_powerinfo'
class CloudsinoProductnetwork(models.Model):
ip = models.CharField(max_length=128)
netmask = models.CharField(max_length=128)
gateway = models.CharField(max_length=128)
mac = models.CharField(max_length=128)
os = models.CharField(max_length=128)
remote_type = models.CharField(max_length=128)
remote_port = models.CharField(max_length=128)
ethernet_switch = models.CharField(max_length=128)
swith_port = models.CharField(max_length=128)
swith_mac = models.CharField(max_length=128)
distribution_frame = models.CharField(max_length=128)
distribution = models.CharField(max_length=128)
device = models.ForeignKey(CloudsinoDevice, blank=True, null=True)
class Meta:
managed = False
db_table = 'cloudsino_productnetwork'
class CloudsinoPurchasewarrantyinfo(models.Model):
date_manuf = models.CharField(max_length=128)
expiredate = models.CharField(max_length=128)
price = models.CharField(max_length=128)
purchase_order = models.CharField(max_length=128)
purchase_order_name = models.CharField(max_length=128)
purchase_supply = models.CharField(max_length=128)
serviceagent = models.CharField(max_length=128)
warrantyitem = models.CharField(db_column='warrantyItem', max_length=128) # Field name made lowercase.
warrantyperiod = models.CharField(db_column='warrantyPeriod', max_length=128) # Field name made lowercase.
warrantystartdate = models.CharField(db_column='warrantyStartDate', max_length=128) # Field name made lowercase.
warrantytype = models.CharField(db_column='warrantyType', max_length=128) # Field name made lowercase.
device = models.ForeignKey(CloudsinoDevice, blank=True, null=True)
class Meta:
managed = False
db_table = 'cloudsino_purchasewarrantyinfo'
class CloudsinoRaidinfo(models.Model):
name = models.CharField(max_length=128)
type = models.CharField(max_length=128)
cachesize = models.CharField(max_length=128)
speed = models.CharField(max_length=128)
manufacturer = models.CharField(max_length=128)
partnumber = models.CharField(max_length=128)
serialnumber = models.CharField(max_length=128)
index = models.CharField(max_length=128)
device = models.ForeignKey(CloudsinoDevice, blank=True, null=True)
class Meta:
managed = False
db_table = 'cloudsino_raidinfo'
class DjangoMigrations(models.Model):
app = models.CharField(max_length=255)
name = models.CharField(max_length=255)
applied = models.DateTimeField()
class Meta:
managed = False
db_table = 'django_migrations'

补充知识：Django使用数据库生成模型类

正常的开发流程

在models.py中定义模型类，要求继承自models.Model

把应用加入settings.py文件的installed_app项

生成迁移文件

执行迁移生成表

使用模型类进行crud操作

使用数据库生成模型类