Custom command ignoring tenant

[perrohunter]

Hi, I'm writing a custom command and I'm realizing that even if I specify a --schema when running the custom command with tenant_command some times I'm getting error:

django.db.utils.ProgrammingError: relation "my_table" does not exist
LINE 1: SELECT (1) AS "a" FROM "my_table" WHERE "my_tabl...

I've notice that this happens when I'm trying to access a tenant app and suddenly some models are not properly tenant configured and throw the error.

Any away I can ensure the right schema is properly configured?

This only happens when running code through a tenant_command where I'm loading modules dynamically and one of them causes an exception.

My Logic:

1. run ./manage.py tenant_command demodata
   my demodata command looks through all the django applications, find the ones containing a demo folder and loads each file in it the calls a install() method sample gist

2. demodata command files two files cats.py and dogs.py, it loads them and then calls a method first on cats.py then dogs.py

3. cats.py fails with an exception "integrity bla bla, duplicate key" so far, everything is as expected

4. dogs.py gets run and upon executing the first db query Dogs.objects.filter(goodBoy=True) it fails with

django.db.utils.ProgrammingError: relation "pets_dogs" does not exist
LINE 1: SELECT (1) AS "a" FROM "pets_dogs" WHERE "pets_dog...
                               ^

this is a really weird scenario, if no exception is caused by cats.py then dogs.py runs just fine

[perrohunter]

So I found the cause, for some reason when I cause a exception on the database side, let's say an Integrity Error which raises a django.db.utils.IntegrityError for some reason a new cursor gets created on the django side, this new cursor doesn't have the proper search_path but the _cursor() funcion on base.py things it does and therefore it doesn't re-set the search_path a way around this is to monitor if the cursor we are getting is different from the previous cursor we got.

New attribute of the DatabaseWrapper

_previous_cursor = None

and inside _cursor() validation of search_path

if (not get_limit_set_calls()) or not self.search_path_set or self._previous_cursor != cursor:
            self._previous_cursor = cursor

[tomturner]

@perrohunter Thank you I will have a look at the pull request

[tomturner]

Merged