from __future__ import absolute_import
import datetime
import unittest
from django.test import TransactionTestCase
from django.db import connection, DatabaseError, IntegrityError
from django.db.models.fields import IntegerField, TextField, CharField, SlugField
from django.db.models.fields.related import ManyToManyField, ForeignKey
from django.db.transaction import atomic
from .models import (Author, AuthorWithM2M, Book, BookWithLongName,
BookWithSlug, BookWithM2M, Tag, TagIndexed, TagM2MTest, TagUniqueRename,
UniqueTest)
class SchemaTests(TransactionTestCase):
"""
Tests that the schema-alteration code works correctly.
Be aware that these tests are more liable than most to false results,
as sometimes the code to check if a test has worked is almost as complex
as the code it is testing.
"""
available_apps = []
models = [
Author, AuthorWithM2M, Book, BookWithLongName, BookWithSlug,
BookWithM2M, Tag, TagIndexed, TagM2MTest, TagUniqueRename, UniqueTest,
]
# Utility functions
def tearDown(self):
# Delete any tables made for our models
self.delete_tables()
def delete_tables(self):
"Deletes all model tables for our models for a clean test environment"
cursor = connection.cursor()
connection.disable_constraint_checking()
table_names = connection.introspection.table_names(cursor)
for model in self.models:
# Remove any M2M tables first
for field in model._meta.local_many_to_many:
with atomic():
tbl = field.rel.through._meta.db_table
if tbl in table_names:
cursor.execute(connection.schema_editor().sql_delete_table % {
"table": connection.ops.quote_name(tbl),
})
table_names.remove(tbl)
# Then remove the main tables
with atomic():
tbl = model._meta.db_table
if tbl in table_names:
cursor.execute(connection.schema_editor().sql_delete_table % {
"table": connection.ops.quote_name(tbl),
})
table_names.remove(tbl)
connection.enable_constraint_checking()
def column_classes(self, model):
cursor = connection.cursor()
columns = dict(
(d[0], (connection.introspection.get_field_type(d[1], d), d))
for d in connection.introspection.get_table_description(
cursor,
model._meta.db_table,
)
)
# SQLite has a different format for field_type
for name, (type, desc) in columns.items():
if isinstance(type, tuple):
columns[name] = (type[0], desc)
# SQLite also doesn't error properly
if not columns:
raise DatabaseError("Table does not exist (empty pragma)")
return columns
# Tests
def test_creation_deletion(self):
"""
Tries creating a model's table, and then deleting it.
"""
# Create the table
with connection.schema_editor() as editor:
editor.create_model(Author)
# Check that it's there
list(Author.objects.all())
# Clean up that table
with connection.schema_editor() as editor:
editor.delete_model(Author)
# Check that it's gone
self.assertRaises(
DatabaseError,
lambda: list(Author.objects.all()),
)
@unittest.skipUnless(connection.features.supports_foreign_keys, "No FK support")
def test_fk(self):
"Tests that creating tables out of FK order, then repointing, works"
# Create the table
with connection.schema_editor() as editor:
editor.create_model(Book)
editor.create_model(Author)
editor.create_model(Tag)
# Check that initial tables are there
list(Author.objects.all())
list(Book.objects.all())
# Make sure the FK constraint is present
with self.assertRaises(IntegrityError):
Book.objects.create(
author_id=1,
title="Much Ado About Foreign Keys",
pub_date=datetime.datetime.now(),
)
# Repoint the FK constraint
new_field = ForeignKey(Tag)
new_field.set_attributes_from_name("author")
with connection.schema_editor() as editor:
editor.alter_field(
Book,
Book._meta.get_field_by_name("author")[0],
new_field,
strict=True,
)
# Make sure the new FK constraint is present
constraints = connection.introspection.get_constraints(connection.cursor(), Book._meta.db_table)
for name, details in constraints.items():
if details['columns'] == ["author_id"] and details['foreign_key']:
self.assertEqual(details['foreign_key'], ('schema_tag', 'id'))
break
else:
self.fail("No FK constraint for author_id found")
def test_add_field(self):
"""
Tests adding fields to models
"""
# Create the table
with connection.schema_editor() as editor:
editor.create_model(Author)
# Ensure there's no age field
columns = self.column_classes(Author)
self.assertNotIn("age", columns)
# Alter the name field to a TextField
new_field = IntegerField(null=True)
new_field.set_attributes_from_name("age")
with connection.schema_editor() as editor:
editor.add_field(
Author,
new_field,
)
# Ensure the field is right afterwards
columns = self.column_classes(Author)
self.assertEqual(columns['age'][0], "IntegerField")
self.assertEqual(columns['age'][1][6], True)
def test_alter(self):
"""
Tests simple altering of fields
"""
# Create the table
with connection.schema_editor() as editor:
editor.create_model(Author)
# Ensure the field is right to begin with
columns = self.column_classes(Author)
self.assertEqual(columns['name'][0], "CharField")
self.assertEqual(bool(columns['name'][1][6]), bool(connection.features.interprets_empty_strings_as_nulls))
# Alter the name field to a TextField
new_field = TextField(null=True)
new_field.set_attributes_from_name("name")
with connection.schema_editor() as editor:
editor.alter_field(
Author,
Author._meta.get_field_by_name("name")[0],
new_field,
strict=True,
)
# Ensure the field is right afterwards
columns = self.column_classes(Author)
self.assertEqual(columns['name'][0], "TextField")
self.assertEqual(columns['name'][1][6], True)
# Change nullability again
new_field2 = TextField(null=False)
new_field2.set_attributes_from_name("name")
with connection.schema_editor() as editor:
editor.alter_field(
Author,
new_field,
new_field2,
strict=True,
)
# Ensure the field is right afterwards
columns = self.column_classes(Author)
self.assertEqual(columns['name'][0], "TextField")
self.assertEqual(bool(columns['name'][1][6]), False)
def test_rename(self):
"""
Tests simple altering of fields
"""
# Create the table
with connection.schema_editor() as editor:
editor.create_model(Author)
# Ensure the field is right to begin with
columns = self.column_classes(Author)
self.assertEqual(columns['name'][0], "CharField")
self.assertNotIn("display_name", columns)
# Alter the name field's name
new_field = CharField(max_length=254)
new_field.set_attributes_from_name("display_name")
with connection.schema_editor() as editor:
editor.alter_field(
Author,
Author._meta.get_field_by_name("name")[0],
new_field,
strict=True,
)
# Ensure the field is right afterwards
columns = self.column_classes(Author)
self.assertEqual(columns['display_name'][0], "CharField")
self.assertNotIn("name", columns)
def test_m2m_create(self):
"""
Tests M2M fields on models during creation
"""
# Create the tables
with connection.schema_editor() as editor:
editor.create_model(Author)
editor.create_model(TagM2MTest)
editor.create_model(BookWithM2M)
# Ensure there is now an m2m table there
columns = self.column_classes(BookWithM2M._meta.get_field_by_name("tags")[0].rel.through)
self.assertEqual(columns['tagm2mtest_id'][0], "IntegerField")
def test_m2m(self):
"""
Tests adding/removing M2M fields on models
"""
# Create the tables
with connection.schema_editor() as editor:
editor.create_model(AuthorWithM2M)
editor.create_model(TagM2MTest)
# Create an M2M field
new_field = ManyToManyField("schema.TagM2MTest", related_name="authors")
new_field.contribute_to_class(AuthorWithM2M, "tags")
try:
# Ensure there's no m2m table there
self.assertRaises(DatabaseError, self.column_classes, new_field.rel.through)
# Add the field
with connection.schema_editor() as editor:
editor.add_field(
Author,
new_field,
)
# Ensure there is now an m2m table there
columns = self.column_classes(new_field.rel.through)
self.assertEqual(columns['tagm2mtest_id'][0], "IntegerField")
# Remove the M2M table again
with connection.schema_editor() as editor:
editor.remove_field(
Author,
new_field,
)
# Ensure there's no m2m table there
self.assertRaises(DatabaseError, self.column_classes, new_field.rel.through)
finally:
# Cleanup model states
AuthorWithM2M._meta.local_many_to_many.remove(new_field)
def test_m2m_repoint(self):
"""
Tests repointing M2M fields
"""
# Create the tables
with connection.schema_editor() as editor:
editor.create_model(Author)
editor.create_model(BookWithM2M)
editor.create_model(TagM2MTest)
editor.create_model(UniqueTest)
# Ensure the M2M exists and points to TagM2MTest
constraints = connection.introspection.get_constraints(connection.cursor(), BookWithM2M._meta.get_field_by_name("tags")[0].rel.through._meta.db_table)
if connection.features.supports_foreign_keys:
for name, details in constraints.items():
if details['columns'] == ["tagm2mtest_id"] and details['foreign_key']:
self.assertEqual(details['foreign_key'], ('schema_tagm2mtest', 'id'))
break
else:
self.fail("No FK constraint for tagm2mtest_id found")
# Repoint the M2M
new_field = ManyToManyField(UniqueTest)
new_field.contribute_to_class(BookWithM2M, "uniques")
try:
with connection.schema_editor() as editor:
editor.alter_field(
Author,
BookWithM2M._meta.get_field_by_name("tags")[0],
new_field,
)
# Ensure old M2M is gone
self.assertRaises(DatabaseError, self.column_classes, BookWithM2M._meta.get_field_by_name("tags")[0].rel.through)
# Ensure the new M2M exists and points to UniqueTest
constraints = connection.introspection.get_constraints(connection.cursor(), new_field.rel.through._meta.db_table)
if connection.features.supports_foreign_keys:
for name, details in constraints.items():
if details['columns'] == ["uniquetest_id"] and details['foreign_key']:
self.assertEqual(details['foreign_key'], ('schema_uniquetest', 'id'))
break
else:
self.fail("No FK constraint for uniquetest_id found")
finally:
# Cleanup through table separately
with connection.schema_editor() as editor:
editor.remove_field(BookWithM2M, BookWithM2M._meta.get_field_by_name("uniques")[0])
# Cleanup model states
BookWithM2M._meta.local_many_to_many.remove(new_field)
del BookWithM2M._meta._m2m_cache
@unittest.skipUnless(connection.features.supports_check_constraints, "No check constraints")
def test_check_constraints(self):
"""
Tests creating/deleting CHECK constraints
"""
# Create the tables
with connection.schema_editor() as editor:
editor.create_model(Author)
# Ensure the constraint exists
constraints = connection.introspection.get_constraints(connection.cursor(), Author._meta.db_table)
for name, details in constraints.items():
if details['columns'] == ["height"] and details['check']:
break
else:
self.fail("No check constraint for height found")
# Alter the column to remove it
new_field = IntegerField(null=True, blank=True)
new_field.set_attributes_from_name("height")
with connection.schema_editor() as editor:
editor.alter_field(
Author,
Author._meta.get_field_by_name("height")[0],
new_field,
strict=True,
)
constraints = connection.introspection.get_constraints(connection.cursor(), Author._meta.db_table)
for name, details in constraints.items():
if details['columns'] == ["height"] and details['check']:
self.fail("Check constraint for height found")
# Alter the column to re-add it
with connection.schema_editor() as editor:
editor.alter_field(
Author,
new_field,
Author._meta.get_field_by_name("height")[0],
strict=True,
)
constraints = connection.introspection.get_constraints(connection.cursor(), Author._meta.db_table)
for name, details in constraints.items():
if details['columns'] == ["height"] and details['check']:
break
else:
self.fail("No check constraint for height found")
def test_unique(self):
"""
Tests removing and adding unique constraints to a single column.
"""
# Create the table
with connection.schema_editor() as editor:
editor.create_model(Tag)
# Ensure the field is unique to begin with
Tag.objects.create(title="foo", slug="foo")
self.assertRaises(IntegrityError, Tag.objects.create, title="bar", slug="foo")
Tag.objects.all().delete()
# Alter the slug field to be non-unique
new_field = SlugField(unique=False)
new_field.set_attributes_from_name("slug")
with connection.schema_editor() as editor:
editor.alter_field(
Tag,
Tag._meta.get_field_by_name("slug")[0],
new_field,
strict=True,
)
# Ensure the field is no longer unique
Tag.objects.create(title="foo", slug="foo")
Tag.objects.create(title="bar", slug="foo")
Tag.objects.all().delete()
# Alter the slug field to be unique
new_new_field = SlugField(unique=True)
new_new_field.set_attributes_from_name("slug")
with connection.schema_editor() as editor:
editor.alter_field(
Tag,
new_field,
new_new_field,
strict=True,
)
# Ensure the field is unique again
Tag.objects.create(title="foo", slug="foo")
self.assertRaises(IntegrityError, Tag.objects.create, title="bar", slug="foo")
Tag.objects.all().delete()
# Rename the field
new_field = SlugField(unique=False)
new_field.set_attributes_from_name("slug2")
with connection.schema_editor() as editor:
editor.alter_field(
Tag,
Tag._meta.get_field_by_name("slug")[0],
TagUniqueRename._meta.get_field_by_name("slug2")[0],
strict=True,
)
# Ensure the field is still unique
TagUniqueRename.objects.create(title="foo", slug2="foo")
self.assertRaises(IntegrityError, TagUniqueRename.objects.create, title="bar", slug2="foo")
Tag.objects.all().delete()
def test_unique_together(self):
"""
Tests removing and adding unique_together constraints on a model.
"""
# Create the table
with connection.schema_editor() as editor:
editor.create_model(UniqueTest)
# Ensure the fields are unique to begin with
UniqueTest.objects.create(year=2012, slug="foo")
UniqueTest.objects.create(year=2011, slug="foo")
UniqueTest.objects.create(year=2011, slug="bar")
self.assertRaises(IntegrityError, UniqueTest.objects.create, year=2012, slug="foo")
UniqueTest.objects.all().delete()
# Alter the model to it's non-unique-together companion
with connection.schema_editor() as editor:
editor.alter_unique_together(
UniqueTest,
UniqueTest._meta.unique_together,
[],
)
# Ensure the fields are no longer unique
UniqueTest.objects.create(year=2012, slug="foo")
UniqueTest.objects.create(year=2012, slug="foo")
UniqueTest.objects.all().delete()
# Alter it back
new_new_field = SlugField(unique=True)
new_new_field.set_attributes_from_name("slug")
with connection.schema_editor() as editor:
editor.alter_unique_together(
UniqueTest,
[],
UniqueTest._meta.unique_together,
)
# Ensure the fields are unique again
UniqueTest.objects.create(year=2012, slug="foo")
self.assertRaises(IntegrityError, UniqueTest.objects.create, year=2012, slug="foo")
UniqueTest.objects.all().delete()
def test_index_together(self):
"""
Tests removing and adding index_together constraints on a model.
"""
# Create the table
with connection.schema_editor() as editor:
editor.create_model(Tag)
# Ensure there's no index on the year/slug columns first
self.assertEqual(
False,
any(
c["index"]
for c in connection.introspection.get_constraints(connection.cursor(), "schema_tag").values()
if c['columns'] == ["slug", "title"]
),
)
# Alter the model to add an index
with connection.schema_editor() as editor:
editor.alter_index_together(
Tag,
[],
[("slug", "title")],
)
# Ensure there is now an index
self.assertEqual(
True,
any(
c["index"]
for c in connection.introspection.get_constraints(connection.cursor(), "schema_tag").values()
if c['columns'] == ["slug", "title"]
),
)
# Alter it back
new_new_field = SlugField(unique=True)
new_new_field.set_attributes_from_name("slug")
with connection.schema_editor() as editor:
editor.alter_index_together(
Tag,
[("slug", "title")],
[],
)
# Ensure there's no index
self.assertEqual(
False,
any(
c["index"]
for c in connection.introspection.get_constraints(connection.cursor(), "schema_tag").values()
if c['columns'] == ["slug", "title"]
),
)
def test_create_index_together(self):
"""
Tests creating models with index_together already defined
"""
# Create the table
with connection.schema_editor() as editor:
editor.create_model(TagIndexed)
# Ensure there is an index
self.assertEqual(
True,
any(
c["index"]
for c in connection.introspection.get_constraints(connection.cursor(), "schema_tagindexed").values()
if c['columns'] == ["slug", "title"]
),
)
def test_db_table(self):
"""
Tests renaming of the table
"""
# Create the table
with connection.schema_editor() as editor:
editor.create_model(Author)
# Ensure the table is there to begin with
columns = self.column_classes(Author)
self.assertEqual(columns['name'][0], "CharField")
# Alter the table
with connection.schema_editor() as editor:
editor.alter_db_table(
Author,
"schema_author",
"schema_otherauthor",
)
# Ensure the table is there afterwards
Author._meta.db_table = "schema_otherauthor"
columns = self.column_classes(Author)
self.assertEqual(columns['name'][0], "CharField")
# Alter the table again
with connection.schema_editor() as editor:
editor.alter_db_table(
Author,
"schema_otherauthor",
"schema_author",
)
# Ensure the table is still there
Author._meta.db_table = "schema_author"
columns = self.column_classes(Author)
self.assertEqual(columns['name'][0], "CharField")
def test_indexes(self):
"""
Tests creation/altering of indexes
"""
# Create the table
with connection.schema_editor() as editor:
editor.create_model(Author)
editor.create_model(Book)
# Ensure the table is there and has the right index
self.assertIn(
"title",
connection.introspection.get_indexes(connection.cursor(), Book._meta.db_table),
)
# Alter to remove the index
new_field = CharField(max_length=100, db_index=False)
new_field.set_attributes_from_name("title")
with connection.schema_editor() as editor:
editor.alter_field(
Book,
Book._meta.get_field_by_name("title")[0],
new_field,
strict=True,
)
# Ensure the table is there and has no index
self.assertNotIn(
"title",
connection.introspection.get_indexes(connection.cursor(), Book._meta.db_table),
)
# Alter to re-add the index
with connection.schema_editor() as editor:
editor.alter_field(
Book,
new_field,
Book._meta.get_field_by_name("title")[0],
strict=True,
)
# Ensure the table is there and has the index again
self.assertIn(
"title",
connection.introspection.get_indexes(connection.cursor(), Book._meta.db_table),
)
# Add a unique column, verify that creates an implicit index
with connection.schema_editor() as editor:
editor.add_field(
Book,
BookWithSlug._meta.get_field_by_name("slug")[0],
)
self.assertIn(
"slug",
connection.introspection.get_indexes(connection.cursor(), Book._meta.db_table),
)
# Remove the unique, check the index goes with it
new_field2 = CharField(max_length=20, unique=False)
new_field2.set_attributes_from_name("slug")
with connection.schema_editor() as editor:
editor.alter_field(
BookWithSlug,
BookWithSlug._meta.get_field_by_name("slug")[0],
new_field2,
strict=True,
)
self.assertNotIn(
"slug",
connection.introspection.get_indexes(connection.cursor(), Book._meta.db_table),
)
def test_primary_key(self):
"""
Tests altering of the primary key
"""
# Create the table
with connection.schema_editor() as editor:
editor.create_model(Tag)
# Ensure the table is there and has the right PK
self.assertTrue(
connection.introspection.get_indexes(connection.cursor(), Tag._meta.db_table)['id']['primary_key'],
)
# Alter to change the PK
new_field = SlugField(primary_key=True)
new_field.set_attributes_from_name("slug")
new_field.model = Tag
with connection.schema_editor() as editor:
editor.remove_field(Tag, Tag._meta.get_field_by_name("id")[0])
editor.alter_field(
Tag,
Tag._meta.get_field_by_name("slug")[0],
new_field,
)
# Ensure the PK changed
self.assertNotIn(
'id',
connection.introspection.get_indexes(connection.cursor(), Tag._meta.db_table),
)
self.assertTrue(
connection.introspection.get_indexes(connection.cursor(), Tag._meta.db_table)['slug']['primary_key'],
)
def test_context_manager_exit(self):
"""
Ensures transaction is correctly closed when an error occurs
inside a SchemaEditor context.
"""
class SomeError(Exception):
pass
try:
with connection.schema_editor():
raise SomeError
except SomeError:
self.assertFalse(connection.in_atomic_block)
def test_foreign_key_index_long_names_regression(self):
"""
Regression test for #21497. Only affects databases that supports
foreign keys.
"""
# Create the table
with connection.schema_editor() as editor:
editor.create_model(Author)
editor.create_model(BookWithLongName)
# Find the properly shortened column name
column_name = connection.ops.quote_name("author_foreign_key_with_really_long_field_name_id")
column_name = column_name[1:-1].lower() # unquote, and, for Oracle, un-upcase
# Ensure the table is there and has an index on the column
self.assertIn(
column_name,
connection.introspection.get_indexes(connection.cursor(), BookWithLongName._meta.db_table),
)