I have a Django application that executes a full-text-search on a database. The view that executes this query is my search_view (I'm ommiting some parts for the sake of simplicity). It just retrieve the results of the search on my Post model and send to the template:
def search_view(request):
posts = m.Post.objects.all()
query = request.GET.get('q')
search_query = SearchQuery(query, config='english')
qs = Post.objects.annotate(
rank=SearchRank(F('vector_column'), search_query) + TrigramSimilarity('post_title', query)
).filter(rank__gte=0.15).order_by('-rank'), 15
)
context = {
results = qs
}
return render(request, 'core/search.html', context)
The application is working just fine. The problem is with a test I created. Here is my tests.py:
class SearchViewTests(TestCase):
def test_search_without_results(self):
"""
If the user's query did not retrieve anything
show him a message informing that
"""
response = self.client.get(reverse('core:search') + '?q=eksjeispowjskdjies')
self.assertEqual(response.status_code, 200)
self.assertContains(response.content, "We didn\'t find anything on our database. We\'re sorry")
This test raises an ProgrammingError exception:
django.db.utils.ProgrammingError: function similarity(character varying, unknown) does not exist
LINE 1: ...plainto_tsquery('english'::regconfig, 'eksjeispowjskdjies')) + SIMILARITY...
^
HINT: No function matches the given name and argument types. You might need to add explicit type casts.
I understand very well this exception, 'cause I got it sometimes. The SIMILARITY function in Postgres accepts two arguments, and both need to be of type TEXT. The exception is raising because the second argument (my query term) is of type UNKNOWN, therefore the function won't work and Django raises the exception. And I don't understand why, because the actual search is working! Even in the shell it works perfectly:
In [1]: from django.test import Client
In [2]: c = Client()
In [3]: response = c.get(reverse('core:search') + '?page=1&q=eksjeispowjskdjies')
In [4]: response
Out[4]: <HttpResponse status_code=200, "text/html; charset=utf-8">
Any ideas about why test doesn't work, but the actual execution of the app works and console test works too?
I had the same problem and this how I solved it in my case:
First of all, the problem was that when Django creates the test database that it is going to use for tests it does not actually run all of your migrations. It simply creates the tables based on your models.
This means that migrations that create some extension in your database, like pg_trgm do not run when creating the test database.
One way to overcome this is to use a fixture in your conftest.py file which will make create said extensions before any tests run.
So, in your conftest.py file add the following:
# the following fixture is used to add the pg_trgm extension to the test database
#pytest.fixture(scope="session", autouse=True)
def django_db_setup(django_db_setup, django_db_blocker):
"""Test session DB setup."""
with django_db_blocker.unblock():
with connection.cursor() as cursor:
cursor.execute("CREATE EXTENSION IF NOT EXISTS pg_trgm;")
You can of course replace pg_trgm with any other extension you require.
PS: You must make sure the extension you are trying to use works for the test database you have chosen. In order to change the database used by Django you can change the value of
DATABASES = {'default': env.db('your_database_connection_uri')}
in your application's settings.py.
In my django project, I have 5 applications, with total 15 models,and all of them are unmanaged. I've written some tests in pytest-django, and when I run them, they fail due to not being able to find tables.
How can I create database entries for all these models so that the tests don't fail?
I was trying to get this to work on Django==4.0.4, pytest-django==4.5.2 and none of the results I could find out there worked for me. This is what I could figure out:
# add this to conftest.py
#pytest.hookimpl(tryfirst=True)
def pytest_runtestloop():
from django.apps import apps
unmanaged_models = []
for app in apps.get_app_configs():
unmanaged_models += [m for m in app.get_models()
if not m._meta.managed]
for m in unmanaged_models:
m._meta.managed = True
It seems intuitive to think that we can achieve what we need by overriding django_db_setup, and that is the solution provided in other answers on SO. However I was not able to get this to work, that might have something to do with changes to the order of execution of these fixtures over the years, I am not sure.
Excerpt from the current pytest-django docs:
pytest-django calls django.setup() automatically. If you want to do anything before this, you have to create a pytest plugin and use the pytest_load_initial_conftests() hook
Read more
You can override the django_db_setup fixture in conftest.py file:
#pytest.fixture(scope="session")
def django_db_setup(django_db_blocker):
with django_db_blocker.unblock():
from django.apps import apps
models_list = apps.get_models()
for model in models_list:
with connection.schema_editor() as schema_editor:
schema_editor.create_model(model)
if model._meta.db_table not in connection.introspection.table_names():
raise ValueError(
"Table `{table_name}` is missing in test database.".format(
table_name=model._meta.db_table
)
)
yield
for model in models_list:
with connection.schema_editor() as schema_editor:
schema_editor.delete_model(model)
This will create the tables for unmanaged models before running tests, and delete those tables after test.
I am currently trying to build an application that manages multiple databases. Since the app will be managing data in 30+ databases I am attempting to generate DATABASE_ROUTERS in the settings file. I cannot directly import the db model into the settings file. I get this error:
django.core.exceptions.AppRegistryNotReady: Apps aren't loaded yet.
This error makes since. Is there a way I can control the sequence of events so that I have access to the database before all of the settings are established on execution? My goal is to automate database connections pulling relevant data from a DB and generate the DATABASE_ROUTERS and DATABASES within the setting file. Is this even possible? Is there a package that I can download that does exactly this?
If you do not know what I am asking please do not down vote just ask me to elaborate.
I was able to figure out how to query the data I needed from my database and import it into the settings file. I created the script below. Keep in mind this can be improved, this is just something I modified from here. This directly queries data from my test db (sqlite3). I use postgreSQL in production. This script should work, with some modification, with PostgreSQL.
As you can see below I am storing the data in dictionaries that is then stored in a list. I then import that list of dictionaries into my settings file. From there I can loop through the list and create my DATABASE_ROUTERS and DATABASES dynamically from the database. I was also able to generate router Classes in my routers.py file by importing the same list. Please comment below if you need me to elaborate further.
import sqlite3
from sqlite3 import Error
dbs = []
def create_connection(db_file):
""" create a database connection to the SQLite database
specified by the db_file
:param db_file: database file
:return: Connection object or None
"""
try:
conn = sqlite3.connect(db_file)
return conn
except Error as e:
print(e)
return None
def select_all_data(conn):
"""
Query all rows in the table
:param conn: the Connection object
:return:
"""
cur = conn.cursor()
cur.execute("SELECT * FROM fund_table")
rows = cur.fetchall()
for row in rows:
print(row)
def select_name_and_db(conn):
"""
Query table by fund_name and db_name
:param conn: the Connection object
:return:
"""
cur = conn.cursor()
cur.execute("SELECT fund_name, db_name FROM fund_table")
rows = cur.fetchall()
for row in rows:
dbs.append({"fund_name": row[0], "db_name": row[1]})
return dbs
def main():
database = "edb.sqlite3"
# create a database connection
conn = create_connection(database)
with conn:
""" select_all_data(conn) """
select_name_and_db(conn)
main()
Make one function that loads this variables and make it async, so after you app is ready you load it, but im not sure is this will work properly
https://hackernoon.com/asynchronous-python-45df84b82434
Dirty Sollution is make 1 file for each BD and you call your settings based in what BD gonna work...
I'm using django with neo4j as database and noemodel as OGM. How do I test it?
When I run python3 manage.py test all the changes, my tests make are left.
And also how do I make two databases, one for testing, another for working in production and specify which one to use how?
I assume the reason all of your changes are being retained is due to using the same neo4j database for testing as you are using in development. Since neomodel isn't integrated tightly with Django it doesn't act the same way Django's ORM does when testing. Django will do some helpful things when you run tests using its ORM, such as creating a test database that will be destroyed upon completion.
With neo4j and neomodel I'd recommend doing the following:
Create a Custom Test Runner
Django enables you to define a custom test runner by setting the TEST_RUNNER settings variable. An extremely simple version of this to get you going would be:
from time import sleep
from subprocess import call
from django.test.runner import DiscoverRunner
class MyTestRunner(DiscoverRunner):
def setup_databases(self, *args, **kwargs):
# Stop your development instance
call("sudo service neo4j-service stop", shell=True)
# Sleep to ensure the service has completely stopped
sleep(1)
# Start your test instance (see section below for more details)
success = call("/path/to/test/db/neo4j-community-2.2.2/bin/neo4j"
" start-no-wait", shell=True)
# Need to sleep to wait for the test instance to completely come up
sleep(10)
if success != 0:
return False
try:
# For neo4j 2.2.x you'll need to set a password or deactivate auth
# Nigel Small's py2neo gives us an easy way to accomplish this
call("source /path/to/virtualenv/bin/activate && "
"/path/to/virtualenv/bin/neoauth "
"neo4j neo4j my-p4ssword")
except OSError:
pass
# Don't import neomodel until we get here because we need to wait
# for the new db to be spawned
from neomodel import db
# Delete all previous entries in the db prior to running tests
query = "match (n)-[r]-() delete n,r"
db.cypher_query(query)
super(MyTestRunner, self).__init__(*args, **kwargs)
def teardown_databases(self, old_config, **kwargs):
from neomodel import db
# Delete all previous entries in the db after running tests
query = "match (n)-[r]-() delete n,r"
db.cypher_query(query)
sleep(1)
# Shut down test neo4j instance
success = call("/path/to/test/db/neo4j-community-2.2.2/bin/neo4j"
" stop", shell=True)
if success != 0:
return False
sleep(1)
# start back up development instance
call("sudo service neo4j-service start", shell=True)
Add a secondary neo4j database
This can be done in a couple ways but to follow along with the test runner above you can download a community distribution from neo4j's website. With this secondary instance you can now swap between which database you'd like to use utilizing the command line statements used in the calls within the test runner.
Wrap Up
This solution assume's you're on a linux box but should be portable to a different OS with minor modifications. Also I'd recommend checking out the Django's Test Runner Docs to expand upon what the test runner can do.
There currently isn't mechanism for working with test databases in neomodel as neo4j only has 1 schema per instance.
However you can override the environment variable NEO4J_REST_URL when running the tests like so
export NEO4J_REST_URL=http://localhost:7473/db/data python3 manage.py test
The way I went about this was to give in and use the existing database, but mark all test-related nodes and detach/delete them when finished. It's obviously not ideal; all your node classes must inherit from NodeBase or risk polluting the db with test data, and if you have unique constraints, those will still be enforced across both live/test data. But it works for my purposes, and I thought I'd share in case it helps someone else.
in myproject/base.py:
from neomodel.properties import Property, validator
from django.conf import settings
class TestModeProperty(Property):
"""
Boolean property that is only set during unit testing.
"""
#validator
def inflate(self, value):
return bool(value)
#validator
def deflate(self, value):
return bool(value)
def __init__(self, *args, **kwargs):
super().__init__(*args, **kwargs)
self.default = True
self.has_default = settings.UNIT_TESTING
class NodeBase(StructuredNode):
__abstract_node__ = True
test_mode = TestModeProperty()
in myproject/test_runner.py:
from django.test.runner import DiscoverRunner
from neomodel import db
class NeoDiscoverRunner(DiscoverRunner):
def teardown_databases(self, old_config, **kwargs):
db.cypher_query(
"""
MATCH (node {test_mode: true})
DETACH DELETE node
"""
)
return super().teardown_databases(old_config, **kwargs)
in settings.py:
UNIT_TESTING = sys.argv[1:2] == ["test"]
TEST_RUNNER = "myproject.test_runner.NeoDiscoverRunner"
I'm trying to run
./manage.py test
But it tells me
Got an error creating the test database: permission denied to create database
Obviously it doesn't have permission to create the database, but I'm on a shared server, so there's not much I can do about that. I can create a new database through the control panel but I don't think there's any way I can let Django do it automatically.
So, can't I create the test database manually and instead tell Django to flush it every time, rather than recreating the whole thing?
I had a similar issue. But I wanted Django to just bypass the creation of a test database for one of my instances (it is not a mirror tough). Following Mark's suggestion, I created a custom test runner, as follows
from django.test.simple import DjangoTestSuiteRunner
class ByPassableDBDjangoTestSuiteRunner(DjangoTestSuiteRunner):
def setup_databases(self, **kwargs):
from django.db import connections
old_names = []
mirrors = []
for alias in connections:
connection = connections[alias]
# If the database is a test mirror, redirect its connection
# instead of creating a test database.
if connection.settings_dict['TEST_MIRROR']:
mirrors.append((alias, connection))
mirror_alias = connection.settings_dict['TEST_MIRROR']
connections._connections[alias] = connections[mirror_alias]
elif connection.settings_dict.get('BYPASS_CREATION','no') == 'no':
old_names.append((connection, connection.settings_dict['NAME']))
connection.creation.create_test_db(self.verbosity, autoclobber=not self.interactive)
return old_names, mirrors
Then I created an extra dict entry in one of my databases entries inside settings.py, 'BYPASS_CREATION':'yes',
Finally, I configured a new TestRunner with
TEST_RUNNER = 'auth.data.runner.ByPassableDBDjangoTestSuiteRunner'
I would suggest using sqlite3 for testing purposes while keeping on using mysql/postgres/etc for production.
This can be achieved by placing this in your settings file:
if 'test' in sys.argv:
DATABASES['default'] = {'ENGINE': 'django.db.backends.sqlite3'}
see Running django tests with sqlite
a temporary sqlite database file will be created in your django project home which you will have write access to. The other advantage is that sqlite3 is much faster for testing. You may however run in to problems if you are using any mysql/postgres specific raw sql (which you should try to avoid anyway).
I think a better solution might be to define your own test runner.
I added this to the comments above but it got kind of lost - recent changes to webfaction make this MUCH easier. You can now create new private database instances.
Follow the instructions there, and when creating a new user make sure to give them the permission to ALTER USER new_username CREATEDB;.
You probably also should change the default cron settings so they don't try to check if this database is up and runnings as frequently.
You could use django-nose as your TEST_RUNNER. Once installed, if you pass the following environment variable, it will not delete and re-create the database (create it manually yourself first).
REUSE_DB=1 ./manage.py test
You can also add the following to settings.py so you don't have to write REUSE_DB=1 every time you want to run tests:
os.environ['REUSE_DB'] = "1"
Note: this will also leave all your tables in the databases which means test setup will be a little quicker, but you will have to manually update the tables (or delete and re-create the database yourself) when you change your models.
my variant to reusing database:
from django.test.simple import DjangoTestSuiteRunner
from django.core.management import call_command
class TestRunner(DjangoTestSuiteRunner):
def setup_databases(self, **kwargs):
from django.db import connections
settings = connections['default'].settings_dict
settings['NAME'] = settings['TEST_NAME']
settings['USER'] = settings['TEST_USER']
settings['PASSWORD'] = settings['TEST_PASSWD']
call_command('syncdb', verbosity=1, interactive=False, load_initial_data=False)
def teardown_databases(self, old_config, **kwargs):
from django.db import connection
cursor = connection.cursor()
cursor.execute('show tables;')
parts = ('DROP TABLE IF EXISTS %s;' % table for (table,) in cursor.fetchall())
sql = 'SET FOREIGN_KEY_CHECKS = 0;\n' + '\n'.join(parts) + 'SET FOREIGN_KEY_CHECKS = 1;\n'
connection.cursor().execute(sql)
The following is a django test suite runner to create database using Webfaction XML-RPC API. Note, setting up the database using the API may take up to a minute, and the script may appear to be stuck momentarily, just wait for a little while.
NOTE: there is a security risk of having control panel password in the webfaction server, because someone breaching into your web server SSH could take over your Webfaction account. If that is a concern, set USE_SESSKEY to True and use the fabric script below this script to pass a session id to the server. The session key expires in 1 hour from the last API call.
File test_runner.py: in the server, you need to configure ./manage.py test to use WebfactionTestRunner
"""
This test runner uses Webfaction XML-RPC API to create and destroy database
"""
# you can put your control panel username and password here.
# NOTE: there is a security risk of having control panel password in
# the webfaction server, because someone breaching into your web server
# SSH could take over your Webfaction account. If that is a concern,
# set USE_SESSKEY to True and use the fabric script below this script to
# generate a session.
USE_SESSKEY = True
# CP_USERNAME = 'webfactionusername' # required if and only if USE_SESSKEY is False
# CP_PASSWORD = 'webfactionpassword' # required if and only if USE_SESSKEY is False
import sys
import os
from django.test.simple import DjangoTestSuiteRunner
from django import db
from webfaction import Webfaction
def get_sesskey():
f = os.path.expanduser("~/sesskey")
sesskey = open(f).read().strip()
os.remove(f)
return sesskey
if USE_SESSKEY:
wf = Webfaction(get_sesskey())
else:
wf = Webfaction()
wf.login(CP_USERNAME, CP_PASSWORD)
def get_db_user_and_type(connection):
db_types = {
'django.db.backends.postgresql_psycopg2': 'postgresql',
'django.db.backends.mysql': 'mysql',
}
return (
connection.settings_dict['USER'],
db_types[connection.settings_dict['ENGINE']],
)
def _create_test_db(self, verbosity, autoclobber):
"""
Internal implementation - creates the test db tables.
"""
test_database_name = self._get_test_db_name()
db_user, db_type = get_db_user_and_type(self.connection)
try:
wf.create_db(db_user, test_database_name, db_type)
except Exception as e:
sys.stderr.write(
"Got an error creating the test database: %s\n" % e)
if not autoclobber:
confirm = raw_input(
"Type 'yes' if you would like to try deleting the test "
"database '%s', or 'no' to cancel: " % test_database_name)
if autoclobber or confirm == 'yes':
try:
if verbosity >= 1:
print("Destroying old test database '%s'..."
% self.connection.alias)
wf.delete_db(test_database_name, db_type)
wf.create_db(db_user, test_database_name, db_type)
except Exception as e:
sys.stderr.write(
"Got an error recreating the test database: %s\n" % e)
sys.exit(2)
else:
print("Tests cancelled.")
sys.exit(1)
db.close_connection()
return test_database_name
def _destroy_test_db(self, test_database_name, verbosity):
"""
Internal implementation - remove the test db tables.
"""
db_user, db_type = get_db_user_and_type(self.connection)
wf.delete_db(test_database_name, db_type)
self.connection.close()
class WebfactionTestRunner(DjangoTestSuiteRunner):
def __init__(self, *args, **kwargs):
# Monkey patch BaseDatabaseCreation with our own version
from django.db.backends.creation import BaseDatabaseCreation
BaseDatabaseCreation._create_test_db = _create_test_db
BaseDatabaseCreation._destroy_test_db = _destroy_test_db
return super(WebfactionTestRunner, self).__init__(*args, **kwargs)
File webfaction.py: this is a thin wrapper for Webfaction API, it need to be importable by both test_runner.py (in the remote server) and the fabfile.py (in the local machine)
import xmlrpclib
class Webfaction(object):
def __init__(self, sesskey=None):
self.connection = xmlrpclib.ServerProxy("https://api.webfaction.com/")
self.sesskey = sesskey
def login(self, username, password):
self.sesskey, _ = self.connection.login(username, password)
def create_db(self, db_user, db_name, db_type):
""" Create a database owned by db_user """
self.connection.create_db(self.sesskey, db_name, db_type, 'unused')
# deletes the default user created by Webfaction API
self.connection.make_user_owner_of_db(self.sesskey, db_user, db_name, db_type)
self.connection.delete_db_user(self.sesskey, db_name, db_type)
def delete_db(self, db_name, db_type):
try:
self.connection.delete_db_user(self.sesskey, db_name, db_type)
except xmlrpclib.Fault as e:
print 'ignored error:', e
try:
self.connection.delete_db(self.sesskey, db_name, db_type)
except xmlrpclib.Fault as e:
print 'ignored error:', e
File fabfile.py: A sample fabric script to generate session key, needed only if USE_SESSKEY=True
from fabric.api import *
from fabric.operations import run, put
from webfaction import Webfaction
import io
env.hosts = ["webfactionusername#webfactionusername.webfactional.com"]
env.password = "webfactionpassword"
def run_test():
wf = Webfaction()
wf.login(env.hosts[0].split('#')[0], env.password)
sesskey_file = '~/sesskey'
sesskey = wf.sesskey
try:
put(io.StringIO(unicode(sesskey)), sesskey_file, mode='0600')
# put your test code here
# e.g. run('DJANGO_SETTINGS_MODULE=settings /path/to/virtualenv/python /path/to/manage.py test --testrunner=test_runner.WebfactionTestRunner')
raise Exception('write your test here')
finally:
run("rm -f %s" % sesskey_file)
The accepted answer didn't work for me. It's so outdated, that it didn't run on my legacy codebase with djano 1.5.
I wrote a blogpost entirely describing how I solved this issue by creating an alternative test runner and changing django settings to provide all the required config and to use new test runner.
You need to specify a sqlite ENGINE when using unit tests. Open the settings.py and add the just after DATABASES section:
import sys
if 'test' in sys.argv or 'test_coverage' in sys.argv: #Covers regular testing and django-coverage
DATABASES['default']['ENGINE'] = 'django.db.backends.sqlite3'
DATABASES['default']['NAME'] = ':memory:'
Modify the following methods in django/db/backends/creation.py:
def _destroy_test_db(self, test_database_name, verbosity):
"Internal implementation - remove the test db tables."
# Remove the test database to clean up after
# 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.
self._set_test_dict()
cursor = self.connection.cursor()
self.set_autocommit()
time.sleep(1) # To avoid "database is being accessed by other users" errors.
cursor.execute("""SELECT table_name FROM information_schema.tables WHERE table_schema='public'""")
rows = cursor.fetchall()
for row in rows:
try:
print "Dropping table '%s'" % row[0]
cursor.execute('drop table %s cascade ' % row[0])
except:
print "Couldn't drop '%s'" % row[0]
#cursor.execute("DROP DATABASE %s" % self.connection.ops.quote_name(test_database_name))
self.connection.close()
def _create_test_db(self, verbosity, autoclobber):
"Internal implementation - creates the test db tables."
suffix = self.sql_table_creation_suffix()
if self.connection.settings_dict['TEST_NAME']:
test_database_name = self.connection.settings_dict['TEST_NAME']
else:
test_database_name = TEST_DATABASE_PREFIX + self.connection.settings_dict['NAME']
qn = self.connection.ops.quote_name
# Create the test database and connect to it. We need to autocommit
# if the database supports it because PostgreSQL doesn't allow
# CREATE/DROP DATABASE statements within transactions.
self._set_test_dict()
cursor = self.connection.cursor()
self.set_autocommit()
return test_database_name
def _set_test_dict(self):
if "TEST_NAME" in self.connection.settings_dict:
self.connection.settings_dict["NAME"] = self.connection.settings_dict["TEST_NAME"]
if "TEST_USER" in self.connection.settings_dict:
self.connection.settings_dict['USER'] = self.connection.settings_dict["TEST_USER"]
if "TEST_PASSWORD" in self.connection.settings_dict:
self.connection.settings_dict['PASSWORD'] = self.connection.settings_dict["TEST_PASSWORD"]
Seems to work... just add the extra settings to your settings.py if you need 'em.
Simple workaround: change TEST_DATABASE_PREFIX in django/db/backends/base/creation.py as you like.