[1.7.x] Added feature flags for introspection capabilities.

Backport of 99d9fa32 from master
This commit is contained in:
Aymeric Augustin 2014-05-07 22:14:39 +02:00
parent 92a1e71100
commit 7194d40236
7 changed files with 88 additions and 44 deletions

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@ -616,6 +616,8 @@ class BaseDatabaseFeatures(object):
supports_subqueries_in_group_by = True
supports_bitwise_or = True
supports_boolean_type = True
supports_binary_field = True
# Do time/datetime fields have microsecond precision?
@ -660,6 +662,9 @@ class BaseDatabaseFeatures(object):
# Does the backend reset sequences between tests?
supports_sequence_reset = True
# Can the backend determine reliably the length of a CharField?
can_introspect_max_length = True
# Confirm support for introspected foreign keys
# Every database can do this reliably, except MySQL,
# which can't do it for MyISAM tables
@ -668,6 +673,24 @@ class BaseDatabaseFeatures(object):
# Can the backend introspect an AutoField, instead of an IntegerField?
can_introspect_autofield = False
# Can the backend introspect a BigIntegerField, instead of an IntegerField?
can_introspect_big_integer_field = True
# Can the backend introspect an BinaryField, instead of an TextField?
can_introspect_binary_field = True
# Can the backend introspect an IPAddressField, instead of an CharField?
can_introspect_ip_address_field = False
# Can the backend introspect a PositiveIntegerField, instead of an IntegerField?
can_introspect_positive_integer_field = False
# Can the backend introspect a SmallIntegerField, instead of an IntegerField?
can_introspect_small_integer_field = False
# Can the backend introspect a TimeField, instead of a DateTimeField?
can_introspect_time_field = True
# Support for the DISTINCT ON clause
can_distinct_on_fields = False
@ -714,6 +737,8 @@ class BaseDatabaseFeatures(object):
# Suffix for backends that don't support "SELECT xxx;" queries.
bare_select_suffix = ''
lowercases_column_names = False
def __init__(self, connection):
self.connection = connection

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@ -172,11 +172,13 @@ class DatabaseFeatures(BaseDatabaseFeatures):
has_select_for_update_nowait = False
supports_forward_references = False
supports_long_model_names = False
supports_boolean_type = False
# XXX MySQL DB-API drivers currently fail on binary data on Python 3.
supports_binary_field = six.PY2
supports_microsecond_precision = False
supports_regex_backreferencing = False
supports_date_lookup_using_string = False
can_introspect_binary_field = False
supports_timezones = False
requires_explicit_null_ordering_when_grouping = True
allows_auto_pk_0 = False

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@ -111,6 +111,8 @@ class DatabaseFeatures(BaseDatabaseFeatures):
has_bulk_insert = True
supports_tablespaces = True
supports_sequence_reset = False
can_introspect_max_length = False
can_introspect_time_field = False
atomic_transactions = False
supports_combined_alters = False
nulls_order_largest = True
@ -118,6 +120,7 @@ class DatabaseFeatures(BaseDatabaseFeatures):
connection_persists_old_columns = True
closed_cursor_error_class = InterfaceError
bare_select_suffix = " FROM DUAL"
lowercases_column_names = True
class DatabaseOperations(BaseDatabaseOperations):

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@ -53,6 +53,8 @@ class DatabaseFeatures(BaseDatabaseFeatures):
uses_savepoints = True
supports_tablespaces = True
supports_transactions = True
can_introspect_ip_address_field = True
can_introspect_small_integer_field = True
can_distinct_on_fields = True
can_rollback_ddl = True
supports_combined_alters = True

View File

@ -105,6 +105,8 @@ class DatabaseFeatures(BaseDatabaseFeatures):
supports_foreign_keys = False
supports_check_constraints = False
autocommits_when_autocommit_is_off = True
can_introspect_positive_integer_field = True
can_introspect_small_integer_field = True
supports_transactions = True
atomic_transactions = False
can_rollback_ddl = True

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@ -2,18 +2,13 @@
from __future__ import unicode_literals
import re
from unittest import expectedFailure, skipUnless
from unittest import skipUnless
from django.core.management import call_command
from django.db import connection
from django.test import TestCase, skipUnlessDBFeature
from django.utils.six import PY3, StringIO
if connection.vendor == 'oracle':
expectedFailureOnOracle = expectedFailure
else:
expectedFailureOnOracle = lambda f: f
class InspectDBTestCase(TestCase):
@ -44,30 +39,41 @@ class InspectDBTestCase(TestCase):
return assertFieldType
# Inspecting Oracle DB doesn't produce correct results, see #19884
@expectedFailureOnOracle
def test_field_types(self):
"""Test introspection of various Django field types"""
assertFieldType = self.make_field_type_asserter()
assertFieldType('char_field', "models.CharField(max_length=10)")
assertFieldType('comma_separated_int_field', "models.CharField(max_length=99)")
# Inspecting Oracle DB doesn't produce correct results (#19884):
# - it gets max_length wrong: it returns a number of bytes.
# - it reports fields as blank=True when they aren't.
if (connection.features.can_introspect_max_length and
not connection.features.interprets_empty_strings_as_nulls):
assertFieldType('char_field', "models.CharField(max_length=10)")
assertFieldType('comma_separated_int_field', "models.CharField(max_length=99)")
assertFieldType('date_field', "models.DateField()")
assertFieldType('date_time_field', "models.DateTimeField()")
assertFieldType('email_field', "models.CharField(max_length=75)")
assertFieldType('file_field', "models.CharField(max_length=100)")
assertFieldType('file_path_field', "models.CharField(max_length=100)")
if connection.vendor == 'postgresql':
# Only PostgreSQL has a specific type
if (connection.features.can_introspect_max_length and
not connection.features.interprets_empty_strings_as_nulls):
assertFieldType('email_field', "models.CharField(max_length=75)")
assertFieldType('file_field', "models.CharField(max_length=100)")
assertFieldType('file_path_field', "models.CharField(max_length=100)")
if connection.features.can_introspect_ip_address_field:
assertFieldType('ip_address_field', "models.GenericIPAddressField()")
assertFieldType('gen_ip_adress_field', "models.GenericIPAddressField()")
else:
elif (connection.features.can_introspect_max_length and
not connection.features.interprets_empty_strings_as_nulls):
assertFieldType('ip_address_field', "models.CharField(max_length=15)")
assertFieldType('gen_ip_adress_field', "models.CharField(max_length=39)")
assertFieldType('slug_field', "models.CharField(max_length=50)")
assertFieldType('text_field', "models.TextField()")
assertFieldType('time_field', "models.TimeField()")
assertFieldType('url_field', "models.CharField(max_length=200)")
if (connection.features.can_introspect_max_length and
not connection.features.interprets_empty_strings_as_nulls):
assertFieldType('slug_field', "models.CharField(max_length=50)")
if not connection.features.interprets_empty_strings_as_nulls:
assertFieldType('text_field', "models.TextField()")
if connection.features.can_introspect_time_field:
assertFieldType('time_field', "models.TimeField()")
if (connection.features.can_introspect_max_length and
not connection.features.interprets_empty_strings_as_nulls):
assertFieldType('url_field', "models.CharField(max_length=200)")
def test_number_field_types(self):
"""Test introspection of various Django field types"""
@ -75,34 +81,48 @@ class InspectDBTestCase(TestCase):
if not connection.features.can_introspect_autofield:
assertFieldType('id', "models.IntegerField(primary_key=True) # AutoField?")
assertFieldType('big_int_field', "models.BigIntegerField()")
if connection.vendor == 'mysql':
# No native boolean type on MySQL
assertFieldType('bool_field', "models.IntegerField()")
assertFieldType('null_bool_field', "models.IntegerField(blank=True, null=True)")
if connection.features.can_introspect_big_integer_field:
assertFieldType('big_int_field', "models.BigIntegerField()")
else:
assertFieldType('big_int_field', "models.IntegerField()")
if connection.features.supports_boolean_type:
assertFieldType('bool_field', "models.BooleanField()")
assertFieldType('null_bool_field', "models.NullBooleanField()")
else:
assertFieldType('bool_field', "models.IntegerField()")
assertFieldType('null_bool_field', "models.IntegerField(blank=True, null=True)")
if connection.vendor == 'sqlite':
# Guessed arguments, see #5014
# Guessed arguments on SQLite, see #5014
assertFieldType('decimal_field', "models.DecimalField(max_digits=10, decimal_places=5) "
"# max_digits and decimal_places have been guessed, "
"as this database handles decimal fields as float")
else:
assertFieldType('decimal_field', "models.DecimalField(max_digits=6, decimal_places=1)")
assertFieldType('float_field', "models.FloatField()")
assertFieldType('int_field', "models.IntegerField()")
if connection.vendor == 'sqlite':
if connection.features.can_introspect_positive_integer_field:
assertFieldType('pos_int_field', "models.PositiveIntegerField()")
assertFieldType('pos_small_int_field', "models.PositiveSmallIntegerField()")
else:
# 'unsigned' property undetected on other backends
assertFieldType('pos_int_field', "models.IntegerField()")
if connection.vendor == 'postgresql':
if connection.features.can_introspect_positive_integer_field:
if connection.features.can_introspect_small_integer_field:
assertFieldType('pos_small_int_field', "models.PositiveSmallIntegerField()")
else:
assertFieldType('pos_small_int_field', "models.PositiveIntegerField()")
else:
if connection.features.can_introspect_small_integer_field:
assertFieldType('pos_small_int_field', "models.SmallIntegerField()")
else:
assertFieldType('pos_small_int_field', "models.IntegerField()")
if connection.vendor in ('sqlite', 'postgresql'):
if connection.features.can_introspect_small_integer_field:
assertFieldType('small_int_field', "models.SmallIntegerField()")
else:
assertFieldType('small_int_field', "models.IntegerField()")
@ -156,7 +176,7 @@ class InspectDBTestCase(TestCase):
out = StringIO()
call_command('inspectdb', stdout=out)
output = out.getvalue()
base_name = 'Field' if connection.vendor != 'oracle' else 'field'
base_name = 'field' if connection.features.lowercases_column_names else 'Field'
self.assertIn("field = models.IntegerField()", output)
self.assertIn("field_field = models.IntegerField(db_column='%s_')" % base_name, output)
self.assertIn("field_field_0 = models.IntegerField(db_column='%s__')" % base_name, output)

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@ -1,17 +1,10 @@
from __future__ import unicode_literals
import unittest
from django.db import connection
from django.test import TestCase, skipUnlessDBFeature, skipIfDBFeature
from .models import Reporter, Article
if connection.vendor == 'oracle':
expectedFailureOnOracle = unittest.expectedFailure
else:
expectedFailureOnOracle = lambda f: f
class IntrospectionTests(TestCase):
def test_table_names(self):
@ -61,19 +54,16 @@ class IntrospectionTests(TestCase):
def test_get_table_description_types(self):
with connection.cursor() as cursor:
desc = connection.introspection.get_table_description(cursor, Reporter._meta.db_table)
# The MySQL exception is due to the cursor.description returning the same constant for
# text and blob columns. TODO: use information_schema database to retrieve the proper
# field type on MySQL
self.assertEqual(
[datatype(r[1], r) for r in desc],
['AutoField' if connection.features.can_introspect_autofield else 'IntegerField',
'CharField', 'CharField', 'CharField', 'BigIntegerField',
'BinaryField' if connection.vendor != 'mysql' else 'TextField']
'BinaryField' if connection.features.can_introspect_binary_field else 'TextField']
)
# The following test fails on Oracle due to #17202 (can't correctly
# inspect the length of character columns).
@expectedFailureOnOracle
@skipUnlessDBFeature('can_introspect_max_length')
def test_get_table_description_col_lengths(self):
with connection.cursor() as cursor:
desc = connection.introspection.get_table_description(cursor, Reporter._meta.db_table)