From 51ea30a43bafad40b4a24ad0be346796a9c7ab6a Mon Sep 17 00:00:00 2001
From: Tim Graham <timograham@gmail.com>
Date: Tue, 23 Dec 2014 12:27:49 -0500
Subject: [PATCH] [1.7.x] Fixed #24037 -- Prevented data loss possibility when
changing Meta.managed.
The migrations autodetector now issues AlterModelOptions operations for
Meta.managed changes instead of DeleteModel + CreateModel.
Thanks iambibhas for the report and Simon and Markus for review.
Backport of 061caa5b386681dc7bdef16918873043224a299c from master
---
django/db/migrations/autodetector.py | 29 ++++++++++++++---------
django/db/migrations/operations/models.py | 1 +
docs/releases/1.7.2.txt | 5 ++++
tests/migrations/test_autodetector.py | 25 ++++++++++++++-----
4 files changed, 43 insertions(+), 17 deletions(-)
diff --git a/django/db/migrations/autodetector.py b/django/db/migrations/autodetector.py
index 99951cdae5..b323182df9 100644
--- a/django/db/migrations/autodetector.py
+++ b/django/db/migrations/autodetector.py
@@ -454,8 +454,9 @@ class MigrationAutodetector(object):
We also defer any model options that refer to collections of fields
that might be deferred (e.g. unique_together, index_together).
"""
- added_models = set(self.new_model_keys) - set(self.old_model_keys)
- added_unmanaged_models = set(self.new_unmanaged_keys) - set(self.old_unmanaged_keys)
+ old_keys = set(self.old_model_keys).union(self.old_unmanaged_keys)
+ added_models = set(self.new_model_keys) - old_keys
+ added_unmanaged_models = set(self.new_unmanaged_keys) - old_keys
models = chain(
sorted(added_models, key=self.swappable_first_key, reverse=True),
sorted(added_unmanaged_models, key=self.swappable_first_key, reverse=True)
@@ -630,19 +631,14 @@ class MigrationAutodetector(object):
We also bring forward removal of any model options that refer to
collections of fields - the inverse of generate_created_models().
"""
- deleted_models = set(self.old_model_keys) - set(self.new_model_keys)
- deleted_unmanaged_models = set(self.old_unmanaged_keys) - set(self.new_unmanaged_keys)
+ new_keys = set(self.new_model_keys).union(self.new_unmanaged_keys)
+ deleted_models = set(self.old_model_keys) - new_keys
+ deleted_unmanaged_models = set(self.old_unmanaged_keys) - new_keys
models = chain(sorted(deleted_models), sorted(deleted_unmanaged_models))
for app_label, model_name in models:
model_state = self.from_state.models[app_label, model_name]
model = self.old_apps.get_model(app_label, model_name)
if not model._meta.managed:
- self.add_operation(
- app_label,
- operations.DeleteModel(
- name=model_state.name,
- ),
- )
# Skip here, no need to handle fields for unmanaged models
continue
@@ -952,7 +948,18 @@ class MigrationAutodetector(object):
makes an operation to represent them in state changes (in case Python
code in migrations needs them)
"""
- models_to_check = self.kept_model_keys.union(self.kept_proxy_keys).union(self.kept_unmanaged_keys)
+ models_to_check = self.kept_model_keys.union(
+ self.kept_proxy_keys
+ ).union(
+ self.kept_unmanaged_keys
+ ).union(
+ # unmanaged converted to managed
+ set(self.old_unmanaged_keys).intersection(self.new_model_keys)
+ ).union(
+ # managed converted to unmanaged
+ set(self.old_model_keys).intersection(self.new_unmanaged_keys)
+ )
+
for app_label, model_name in sorted(models_to_check):
old_model_name = self.renamed_models.get((app_label, model_name), model_name)
old_model_state = self.from_state.models[app_label, old_model_name]
diff --git a/django/db/migrations/operations/models.py b/django/db/migrations/operations/models.py
index 75053474a9..bb7f11d90d 100644
--- a/django/db/migrations/operations/models.py
+++ b/django/db/migrations/operations/models.py
@@ -356,6 +356,7 @@ class AlterModelOptions(Operation):
# Model options we want to compare and preserve in an AlterModelOptions op
ALTER_OPTION_KEYS = [
"get_latest_by",
+ "managed",
"ordering",
"permissions",
"default_permissions",
diff --git a/docs/releases/1.7.2.txt b/docs/releases/1.7.2.txt
index 179bd5f7db..309aa736ad 100644
--- a/docs/releases/1.7.2.txt
+++ b/docs/releases/1.7.2.txt
@@ -162,3 +162,8 @@ Bugfixes
* Added ``datetime.time`` support to migrations questioner (:ticket:`23998`).
* Fixed admindocs crash on apps installed as eggs (:ticket:`23525`).
+
+* Changed migrations autodetector to generate an ``AlterModelOptions`` operation
+ instead of ``DeleteModel`` and ``CreateModel`` operations when changing
+ ``Meta.managed``. This prevents data loss when changing ``managed`` from
+ ``False`` to ``True`` and vice versa (:ticket:`24037`).
diff --git a/tests/migrations/test_autodetector.py b/tests/migrations/test_autodetector.py
index 38771f16ac..8beda8e552 100644
--- a/tests/migrations/test_autodetector.py
+++ b/tests/migrations/test_autodetector.py
@@ -1021,7 +1021,7 @@ class AutodetectorTests(TestCase):
# The field name the FK on the book model points to
self.assertEqual(changes['otherapp'][0].operations[0].fields[2][1].rel.field_name, 'pk_field')
- def test_unmanaged(self):
+ def test_unmanaged_create(self):
"""Tests that the autodetector correctly deals with managed models."""
# First, we test adding an unmanaged model
before = self.make_project_state([self.author_empty])
@@ -1031,9 +1031,10 @@ class AutodetectorTests(TestCase):
# Right number/type of migrations?
self.assertNumberMigrations(changes, 'testapp', 1)
self.assertOperationTypes(changes, 'testapp', 0, ["CreateModel"])
- self.assertOperationAttributes(changes, 'testapp', 0, 0, name="AuthorUnmanaged")
- self.assertEqual(changes['testapp'][0].operations[0].options['managed'], False)
+ self.assertOperationAttributes(changes, 'testapp', 0, 0,
+ name="AuthorUnmanaged", options={"managed": False})
+ def test_unmanaged_to_managed(self):
# Now, we test turning an unmanaged model into a managed model
before = self.make_project_state([self.author_empty, self.author_unmanaged])
after = self.make_project_state([self.author_empty, self.author_unmanaged_managed])
@@ -1041,9 +1042,21 @@ class AutodetectorTests(TestCase):
changes = autodetector._detect_changes()
# Right number/type of migrations?
self.assertNumberMigrations(changes, 'testapp', 1)
- self.assertOperationTypes(changes, 'testapp', 0, ["DeleteModel", "CreateModel"])
- self.assertOperationAttributes(changes, 'testapp', 0, 0, name="AuthorUnmanaged")
- self.assertOperationAttributes(changes, 'testapp', 0, 1, name="AuthorUnmanaged")
+ self.assertOperationTypes(changes, 'testapp', 0, ["AlterModelOptions"])
+ self.assertOperationAttributes(changes, 'testapp', 0, 0,
+ name="authorunmanaged", options={})
+
+ def test_managed_to_unmanaged(self):
+ # Now, we turn managed to unmanaged.
+ before = self.make_project_state([self.author_empty, self.author_unmanaged_managed])
+ after = self.make_project_state([self.author_empty, self.author_unmanaged])
+ autodetector = MigrationAutodetector(before, after)
+ changes = autodetector._detect_changes()
+ # Right number/type of migrations?
+ self.assertNumberMigrations(changes, 'testapp', 1)
+ self.assertOperationTypes(changes, "testapp", 0, ["AlterModelOptions"])
+ self.assertOperationAttributes(changes, "testapp", 0, 0,
+ name="authorunmanaged", options={"managed": False})
def test_unmanaged_custom_pk(self):
"""