Commit e953c78e authored by Claude Paroz's avatar Claude Paroz
Browse files

Fixed #16969 -- Don't connect to named database when possible 

Thanks Andreas Pelme for the report and initial patch, and
Aymeric Augustin, Shai Berger and Tim Graham for the reviews.
parent 1830f504

django/db/backends/creation.py

+22 −15
Original line number Diff line number Diff line
@@ -6,6 +6,7 @@ import warnings 
from django.conf import settings

from django.db.utils import load_backend

from django.utils.encoding import force_bytes

from django.utils.functional import cached_property

from django.utils.six.moves import input



from .utils import truncate_name
@@ -29,6 +30,24 @@ class BaseDatabaseCreation(object): 
    def __init__(self, connection):

        self.connection = connection



    @cached_property

    def _nodb_connection(self):

        """

        Alternative connection to be used when there is no need to access

        the main database, specifically for test db creation/deletion.

        This also prevents the production database from being exposed to

        potential child threads while (or after) the test database is destroyed.

        Refs #10868, #17786, #16969.

        """

        settings_dict = self.connection.settings_dict.copy()

        settings_dict['NAME'] = None

        backend = load_backend(settings_dict['ENGINE'])

        nodb_connection = backend.DatabaseWrapper(

             settings_dict,

             alias='__no_db__',

             allow_thread_sharing=False)

        return nodb_connection



    @classmethod

    def _digest(cls, *args):

        """
@@ -386,7 +405,7 @@ class BaseDatabaseCreation(object): 
        qn = self.connection.ops.quote_name



        # Create the test database and connect to it.

        cursor = self.connection.cursor()

        cursor = self._nodb_connection.cursor()

        try:

            cursor.execute(

                "CREATE DATABASE %s %s" % (qn(test_database_name), suffix))
@@ -431,18 +450,7 @@ class BaseDatabaseCreation(object): 
            print("Destroying test database for alias '%s'%s..." % (

                self.connection.alias, test_db_repr))



        # Temporarily use a new connection and a copy of the settings dict.

        # This prevents the production database from being exposed to potential

        # child threads while (or after) the test database is destroyed.

        # Refs #10868 and #17786.

        settings_dict = self.connection.settings_dict.copy()

        settings_dict['NAME'] = old_database_name

        backend = load_backend(settings_dict['ENGINE'])

        new_connection = backend.DatabaseWrapper(

            settings_dict,

            alias='__destroy_test_db__',

            allow_thread_sharing=False)

        new_connection.creation._destroy_test_db(test_database_name, verbosity)

        self._destroy_test_db(test_database_name, verbosity)



    def _destroy_test_db(self, test_database_name, verbosity):

        """
@@ -452,12 +460,11 @@ class BaseDatabaseCreation(object): 
        # ourselves. Connect to the previous database (not the test database)

        # to do so, because it's not allowed to delete a database while being

        # connected to it.

        cursor = self.connection.cursor()

        cursor = self._nodb_connection.cursor()

        # Wait to avoid "database is being accessed by other users" errors.

        time.sleep(1)

        cursor.execute("DROP DATABASE %s"

                       % self.connection.ops.quote_name(test_database_name))

        self.connection.close()



    def set_autocommit(self):

        """

django/db/backends/postgresql_psycopg2/base.py

+3 −2
Original line number Diff line number Diff line
@@ -101,13 +101,14 @@ class DatabaseWrapper(BaseDatabaseWrapper): 


    def get_connection_params(self):

        settings_dict = self.settings_dict

        if not settings_dict['NAME']:

        # None may be used to connect to the default 'postgres' db

        if settings_dict['NAME'] == '':

            from django.core.exceptions import ImproperlyConfigured

            raise ImproperlyConfigured(

                "settings.DATABASES is improperly configured. "

                "Please supply the NAME value.")

        conn_params = {

            'database': settings_dict['NAME'],

            'database': settings_dict['NAME'] or 'postgres',

        }

        conn_params.update(settings_dict['OPTIONS'])

        if 'autocommit' in conn_params:

docs/internals/contributing/writing-code/unit-tests.txt

+11 −7
Original line number Diff line number Diff line
@@ -76,17 +76,21 @@ If you're using a backend that isn't SQLite, you will need to provide other 
details for each database:



* The :setting:`USER` option needs to specify an existing user account

  for the database.

  for the database. That user needs permission to execute ``CREATE DATABASE``

  so that the test database can be created.



* The :setting:`PASSWORD` option needs to provide the password for

  the :setting:`USER` that has been specified.



* The :setting:`NAME` option must be the name of an existing database to

  which the given user has permission to connect. The unit tests will not

  touch this database; the test runner creates a new database whose name

  is :setting:`NAME` prefixed with ``test_``, and this test database is

  deleted when the tests are finished. This means your user account needs

  permission to execute ``CREATE DATABASE``.

Test databases get their names by prepending ``test_`` to the value of the

:setting:`NAME` settings for the databases defined in :setting:`DATABASES`.

These test databases are deleted when the tests are finished.



.. versionchanged:: 1.7



    Before Django 1.7, the :setting:`NAME` setting was mandatory and had to

    be the name of an existing database to which the given user had permission

    to connect.



You will also need to ensure that your database uses UTF-8 as the default

character set. If your database server doesn't use UTF-8 as a default charset,