I have a django application that uses 2 database connections:
- To connect to the actual data the app is to produce
- To a reference master data system, that is maintained completely outside my control
The issue that I'm having, is that my webapp can absolutely NOT touch the data in the 2nd database. I solved most of the issues by using 2 (sub)apps, one for every database connection. I created a router file that router any migration, and writing to the first app
I also made all the models in the 2nd app non managed, using the
model.meta.managed = False
option.
To be sure, the user I connect to the 2nd database has read only access
This works fine for migrations and running. However, when I try to run tests using django testcase, Django tries to delete and create a test_ database on the 2nd database connection.
How can I make sure that Django will NEVER update/delete/insert/drop/truncate over the 2nd connection
How can I run tests, that do not try to create the second database, but do create the first.
Thanks!
edited: code
model (for the 2nd app, that should not be managed):
from django.db import models
class MdmMeta(object):
db_tablespace = 'MDM_ADM'
managed = False
ordering = ['name']
class ActiveManager(models.Manager):
def get_queryset(self):
return super(ActiveManager, self).get_queryset().filter(lifecyclestatus='active')
class MdmType(models.Model):
entity_guid = models.PositiveIntegerField(db_column='ENTITYGUID')
entity_name = models.CharField(max_length=255, db_column='ENTITYNAME')
entry_guid = models.PositiveIntegerField(primary_key=True, db_column='ENTRYGUID')
name = models.CharField(max_length=255, db_column='NAME')
description = models.CharField(max_length=512, db_column='DESCRIPTION')
lifecyclestatus = models.CharField(max_length=255, db_column='LIFECYCLESTATUS')
# active_manager = ActiveManager()
def save(self, *args, **kwargs):
raise Exception('Do not save MDM models!')
def delete(self, *args, **kwargs):
raise Exception('Do not delete MDM models!')
def __str__(self):
return self.name
class Meta(MdmMeta):
abstract = True
# Create your models here.
class MdmSpecies(MdmType):
class Meta(MdmMeta):
db_table = 'MDM_SPECIES'
verbose_name = 'Species'
verbose_name_plural = 'Species'
class MdmVariety(MdmType):
class Meta(MdmMeta):
db_table = 'MDM_VARIETY'
verbose_name = 'Variety'
verbose_name_plural = 'Varieties'
...
router:
__author__ = 'CoesseWa'
class MdmRouter(object):
def db_for_read(self, model, **hints):
if model._meta.app_label == 'mdm':
# return 'default'
return 'mdm_db' # trying to use one database connection
return 'default'
def db_for_write(self, model, **hints):
return 'default'
def allow_relation(self, obj1, obj2, **hints):
return None
def allow_migrate(self, db, model):
if model._meta.app_label == 'mdm':
return False
settings:
DATABASES = {
'default': {
'ENGINE': 'django.db.backends.oracle',
'NAME': '(DESCRIPTION=(ADDRESS_LIST=(ADDRESS=(PROTOCOL=TCP)(HOST=%s)(PORT=1521)))(CONNECT_DATA=(SID=%s)))'
% (get_env_variable('LIMS_MIGRATION_HOST'), get_env_variable('LIMS_MIGRATION_SID')),
'USER': 'LIMS_MIGRATION',
'PASSWORD': get_env_variable('LIMS_MIGRATION_PASSWORD'),
},
'mdm_db': {
'ENGINE': 'django.db.backends.oracle',
'NAME': '(DESCRIPTION=(ADDRESS_LIST=(ADDRESS=(PROTOCOL=TCP)(HOST=GB3P)(PORT=1521)))'
'(CONNECT_DATA=(SID=GB3P)))',
'USER': 'MDM',
'PASSWORD': get_env_variable('MDM_DB_PASSWORD'),
},
}
one testcase:
from django.test.testcases import TestCase
__author__ = 'CoesseWa'
class ModelTest(TestCase):
def test_getting_guid_for_mdm_field(self):
self.assertIsNotNone(1)
output from when running this tests:
...
Destroying old test user...
(before this point, django creates the test database for my first connection = OK)
Creating test user...
=> This next lines should never happen. Fails because I use a read only user (luckily)
Creating test database for alias 'mdm_db'...
Failed (ORA-01031: insufficient privileges
Got an error creating the test database: ORA-01031: insufficient privileges
