Question

我正在使用Django 1.10和Python 2.7进行项目。

我已阅读并尝试根据this page实施数据库路由。我还阅读了很多不同的教程和其他stackoverflow问题。但是，我似乎无法让它发挥作用。

这是我的情景：

我需要默认数据库上的所有分析，auth和admin应用程序模型。然后在另一个单独的数据库上取消应用程序，在另一个单独的数据库上取消驱动应用程序。

这是我正在使用的路由器：

from django.conf import settings


class AppRouter:
    def db_for_read(self, model, **hints):
        if model._meta.app_label == 'analytics':
            return 'default'

        elif model._meta.app_label == 'cancellation':
            return 'cancellations_db'

        elif model._meta.app_label == 'driveractivity':
            return 'driveractivity_db'

        return None

    def db_for_write(self, model, **hints):
        if model._meta.app_label == 'analytics':
            return 'default'

        elif model._meta.app_label == 'cancellation':
            return 'cancellations_db'

        elif model._meta.app_label == 'driveractivity':
            return 'driveractivity_db'

        return None

    def allow_migrate(self, db, app_label, model=None, **hints):    
        if app_label == 'cancellation' and db == 'cancellations_db':
            return True

        if app_label == 'driveractivity' and db == 'driveractivity_db':
            return True

        if app_label in ('analytics', 'auth', 'admin', 'contenttypes', 'sessions', 'rest_framework') and db == 'default':
            return True

        return False

我的数据库设置如下（ settings.py ）：

DATABASES = {
    'default': {
        'ENGINE': 'django.db.backends.mysql',
        'HOST': 'localhost',
        'NAME': 'analytics',
        'USER': 'root'
    },
    'driveractivity_db': {
        'ENGINE': 'django.db.backends.mysql',
        'HOST': 'localhost',
        'PORT': '3306',
        'NAME': 'driveractivity',
        'USER': 'root',
    },
    'cancellations_db': {
        'ENGINE': 'django.db.backends.mysql',
        'HOST': 'localhost',
        'PORT': '3306',
        'NAME': 'teke_cancellation',
        'USER': 'root'
    }
}

DATABASE_ROUTERS = ['analytics.AppRouter.AppRouter']

DB_Mapping = {
    "cancellation": "cancellations_db",
    "driveractivity": "driveractivity_db"
}

models.py - 取消

class Cancellation(models.Model):
    id = models.IntegerField(primary_key=True)
    user = models.EmailField(max_length=255,blank=False)
    time = models.DateField(blank=False)
        created_at = models.DateTimeField(auto_now=True,auto_now_add=False)
    updated_at = models.DateTimeField(auto_now=False,auto_now_add=True)

    class Meta:
        app_label = 'cancellation'


class PenaltyType(models.Model):
    id = models.IntegerField(primary_key=True)
    name = models.CharField(max_length=255,blank=False)
    created_at = models.DateTimeField(auto_now=True,auto_now_add=False)
    updated_at = models.DateTimeField(auto_now=False,auto_now_add=True)

    class Meta:
        app_label = 'cancellation'


class Penalty(models.Model):
    id = models.IntegerField(primary_key=True)
    user = models.EmailField(max_length=255,blank=False)
    meted = models.BooleanField(default=False)
    penalty_type = models.ForeignKey(PenaltyType)
    created_at = models.DateTimeField(auto_now=True,auto_now_add=False)
    updated_at = models.DateTimeField(auto_now=False,auto_now_add=True)

    class Meta:
        app_label = 'cancellation'

models.py - driveractivity

class Activity(models.Model):
    email = models.EmailField(null=False)
    driver_name = models.CharField(max_length=30,null=False)
    vehicle_reg = models.CharField(max_length=30,null=False)
    status = models.CharField(max_length=15)
    desc = models.CharField(max_length=250)
    lng = models.FloatField()
    lat = models.FloatField()
    time = models.DateTimeField()
    created_at = models.DateTimeField(auto_now=True,auto_now_add=False)
    updated_at = models.DateTimeField(auto_now=False,auto_now_add=True)

    class Meta:
        app_label = 'driveractivity'


class DistanceDetails(models.Model):
    email = models.EmailField(null=False)
    driver_name = models.CharField(max_length=30,null=False)
    vehicle_reg = models.CharField(max_length=30,null=False)
    new_lng = models.FloatField()
    new_lat = models.FloatField()
    last_state = models.CharField(max_length=15,null=False)
    last_lng = models.FloatField()
    last_lat = models.FloatField()
    created_at = models.DateTimeField(auto_now=True,auto_now_add=False)
    updated_at = models.DateTimeField(auto_now=False,auto_now_add=True)

    class Meta:
        app_label = 'driveractivity'

已修改 router.py

class AppRouter(object):
    def db_for_read(self, model, **hints):
        return DB_Mapping.get(model._meta.app_label, 'default')

    def db_for_write(self, model, **hints):
        return DB_Mapping.get(model._meta.app_label, 'default')

    def allow_migrate(self, db, app_label, model=None, **hints):
        if app_label in DB_Mapping.keys() or db in DB_Mapping.values():
            return True
        else:
            return None

我有什么问题吗？

Answer 1

检查这是否适合您：

<强> settings.py

DB_Mapping = {
    "cancellation": "cancellation_db",
    "driveractivity": "driveractivity_db",
    ...
}

<强> router.py

from project.settings import DB_Mapping

class MyRouter(object):
    def db_for_read(self, model, **hints):
        return DB_Mapping.get(model._meta.app_label, 'default')

    def db_for_write(self, model, **hints):
        return DB_Mapping.get(model._meta.app_label, 'default')

我使用类似的设置，我根据发出请求的用户组路由到不同的数据库用户。

allow_migrate也可以类似地编写。，如果db == 'default'或if model._meta.app_label in DB_Mapping.keys() or db in DB_Mapping.values(): return True else False

Answer 2

你的线路

DATABASE_ROUTERS = ['analytics.AppRouter.AppRouter']

可能需要改为：

DATABASE_ROUTERS = ['analytics.router.AppRouter']

Django多应用程序数据库路由器无法正常工作

2 个答案: