django 多数据分库

路由策略

# -*- coding: utf-8 -*-
from django.conf import settings

class DatabaseAppsRouter(object):
    """
    A router to control all database operations on models for different
    databases.

    In case an app is not set in settings.DATABASE_APPS_MAPPING, the router
    will fallback to the `default` database.

    Settings example:

    DATABASE_APPS_MAPPING = {'app1': 'db1', 'app2': 'db2'}
    """

    def db_for_read(self, model, **hints):
        """"Point all read operations to the specific database."""
        if model._meta.app_label == 'yw_monitor':
            return 'webmonitor'
        return None

    def db_for_write(self, model, **hints):
        """Point all write operations to the specific database."""
        if model._meta.app_label == 'yw_monitor':
            return 'webmonitor'
        return None

    def allow_relation(self, obj1, obj2, **hints):
        """Allow any relation between apps that use the same database."""
        if obj1._meta.app_label == 'yw_monitor' or obj2._meta.app_label == 'yw_monitor':
            return True
        return None

    def allow_migrate(self, db, app_label, model_name=None, **hints):
        """Make sure that apps only appear in the related database."""

        if app_label == 'yw_monitor':
            return db == 'webmonitor'
        return None