#31615 closed Cleanup/optimization (fixed)
Do not fail migration if postgresql extension is already installed and user is not superuser
Reported by: | minusf | Owned by: | minusf |
---|---|---|---|
Component: | Migrations | Version: | 3.0 |
Severity: | Normal | Keywords: | migration extension postgresql |
Cc: | Triage Stage: | Ready for checkin | |
Has patch: | yes | Needs documentation: | no |
Needs tests: | no | Patch needs improvement: | no |
Easy pickings: | yes | UI/UX: | no |
Description
Currently Django facilitates installing postgres extensions using migration operations: https://docs.djangoproject.com/en/3.0/ref/contrib/postgres/operations/
But having a superuser is a tall order in certain environments, and the manual helpfully points out:
If the Django database user doesn’t have superuser privileges, you’ll have to create the extension outside of Django migrations with a user that has the appropriate privileges.
This is fairly often the case with Salt and other orchestration systems.
However having a non-superuser will break any migrations using these operations because unfortunately CREATE EXTENSION
even with IF NOT EXISTS
still requires superuser privileges... In other words, if the extension is already in place, the migration will fail...
I think a failsafe like this around CREATE/DROP EXTENSION would make the migrations more robust and user friendly.
diff --git a/django/contrib/postgres/operations.py b/django/contrib/postgres/operations.py index 0bb131ddf2..46fc11f63f 100644 --- a/django/contrib/postgres/operations.py +++ b/django/contrib/postgres/operations.py @@ -21,7 +21,13 @@ class CreateExtension(Operation): not router.allow_migrate(schema_editor.connection.alias, app_label) ): return - schema_editor.execute("CREATE EXTENSION IF NOT EXISTS %s" % schema_editor.quote_name(self.name)) + + cur = schema_editor.connection.cursor() + cur.execute("SELECT * FROM pg_extension WHERE extname = %s", [self.name]) + if not cur.fetchone(): + schema_editor.execute( + "CREATE EXTENSION IF NOT EXISTS %s" % schema_editor.quote_name(self.name) + ) # Clear cached, stale oids. get_hstore_oids.cache_clear() get_citext_oids.cache_clear() @@ -33,7 +39,13 @@ class CreateExtension(Operation): def database_backwards(self, app_label, schema_editor, from_state, to_state): if not router.allow_migrate(schema_editor.connection.alias, app_label): return - schema_editor.execute("DROP EXTENSION %s" % schema_editor.quote_name(self.name)) + + cur = schema_editor.connection.cursor() + cur.execute("SELECT * FROM pg_extension WHERE extname = %s", [self.name]) + if cur.fetchone(): + schema_editor.execute( + "DROP EXTENSION %s" % schema_editor.quote_name(self.name) + ) # Clear cached, stale oids. get_hstore_oids.cache_clear() get_citext_oids.cache_clear()
Change History (9)
comment:1 by , 5 years ago
Has patch: | unset |
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Triage Stage: | Unreviewed → Accepted |
Type: | Bug → Cleanup/optimization |
comment:3 by , 5 years ago
please have a look at this one: https://github.com/django/django/pull/12952
git got the better of me :/
comment:4 by , 4 years ago
Needs tests: | set |
---|---|
Patch needs improvement: | set |
comment:5 by , 4 years ago
Needs tests: | unset |
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Owner: | changed from | to
Patch needs improvement: | unset |
Status: | new → assigned |
Triage Stage: | Accepted → Ready for checkin |
I'm in favor. Please check again the
Has patch
box when a GitHub PR is available.