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Can't reference Django database with dj_database_url

I have a Django application using decouple and dj_database_url (it is not on Heroku). If I put my connection information in settings.ini (DB_NAME, DB_USER, DB_PASSWORD, DB_HOST, and DB_PORT) and set up my database connection in settings.py like this:
DATABASES = {
'default': {
'ENGINE': 'django.db.backends.postgresql_psycopg2',
'NAME': config('DB_NAME'),
'USER': config('DB_USER'),
'PASSWORD': config('DB_PASSWORD'),
'HOST': config('DB_HOST'),
'PORT': 'DB_PORT',
}
}
It works fine.
However, if I put this in my settings.ini:
DATABASE_URL=postgres://johndoe:mypassword#123.456.789.000:5000/blog_db
and reference it like this in my settings.py:
DATABASES = {"default": dj_database_url.config(default=config("DATABASE_URL"))}
It doesn't work. I just get a 500 when I try to run my server. I presume there is something wrong with my syntax. Can anyone point out what I'm doing wrong?
Thanks!

Django test with different database user

I want to keep my unit test database completely separate from other environments including using different user credentials. This is mostly to prevent anyone from unintentionally running unit tests against the development database and mangling the dev data or wiping it out entirely if the --keepdb option isn't specified. The code below detects the "test" in the sys args and this seems to work but is very clunky. If I'm missing a better way to do this please advise.
I have separate settings files for each environment so this will only be on the development server where the unit tests are run automatically and won't end up on any production servers.
Environment:
Django 1.11
Python 3.4.x
MariaDB
# this works but is clunky
import sys
if 'test' in sys.argv:
DATABASES = { # test db and user
'default': {
'ENGINE': 'django.db.backends.mysql',
'NAME': 'dev_db_test',
'USER': 'test_user',
'PASSWORD': 'secretpassword',
'HOST': 'the-db-host',
'PORT': '3306',
'TEST': { # redundant but explicit!
'NAME':'dev_db_test',
},
}
}
else:
DATABASES = {
'default': {
'ENGINE': 'django.db.backends.mysql',
'NAME': 'dev_db',
'USER': 'dev_db_user',
'PASSWORD': 'dev_password',
'HOST': 'the-db-host',
'PORT': '3306',
'TEST': {
'NAME':'dev_db_test', # redundant but explicit!
},
}
}
I'd like to do this but unfortunately Django doesn't look at the TEST credentials
# cleaner approach but doesn't work - don't do this!
DATABASES = {
'default': {
'ENGINE': 'django.db.backends.mysql',
'NAME': 'dev_db',
'USER': 'dev_db_user',
'PASSWORD': 'dev_password',
'HOST': 'the-db-host',
'PORT': '3306',
'TEST': {
'NAME':'dev_db_test', # Django uses the test db NAME
'USER':'test_user_ignored', # but ignores the USER and PASSWORD
'PASSWORD':'ignoredpassword',
},
}
}

Would something like this work for your situation?
import sys
if 'test' in sys.argv:
NAME = 'dev_db_test'
USER = 'test_user'
PASSWORD ='secretpassword'
else:
NAME = 'dev_db'
USER = 'dev_db_user'
PASSWORD ='dev_password'
DATABASES ={ # test db and user
'default':
{
'ENGINE': 'django.db.backends.mysql',
'NAME': NAME,
'USER': USER,
'PASSWORD': PASSWORD,
'HOST': 'the-db-host',
'PORT': '3306',
'TEST':
{ # redundant but explicit!
'NAME':'dev_db_test',
},
}
}
print(DATABASES)

AFAIK, you don't need to create a separate test database if you want to run unit tests over it. Here is the documentation link of test database.
It states that:
Tests that require a database (namely, model tests) will not use your “real” (production) database.
Separate, blank databases are created for the tests.
You can follow this link to write your tests and it will not affect your production or development database.

How to configure Django database using Heroku?

I'm using Heroku with Django.
The database is configured in settings.py this way, using the dj-database-url module:
DATABASES = {'default': dj_database_url.config()}
How can I do to add additional parameters, for example ATOMIC_REQUESTS? In a "normal" case I would do like this:
DATABASES = {
'default': {
'ENGINE': 'django.db.backends.postgresql_psycopg2',
'NAME': 'mydatabase',
'USER': 'mydatabaseuser',
'PASSWORD': 'mypassword',
'HOST': '127.0.0.1',
'PORT': '5432',
'ATOMIC_REQUESTS': True,
}
}

DATABASES is just a dictionary: you can add the relevant settings after the initial configuration.
DATABASES = {'default': dj_database_url.config()}
DATABASES['default']['ATOMIC_REQUESTS'] = True

How to set storage engine in Django with MySQL connector/python as backend

I tried setting
DATABASES = {
'default': {
'NAME': 'db',
'ENGINE': 'mysql.connector.django',
'USER': 'dbuser',
'PASSWORD': 'dbpass',
'OPTIONS': {
'autocommit': True,
'init_command' : 'SET storage_engine=INNODB',
},
}
}
(UPD: updated the above code so ppl won't get confused that I am not using django settings the right way)
in Django settings, but this backend doesn't accept such connection option...
http://dev.mysql.com/doc/connector-python/en/connector-python-connectargs.html
is there any other way of doing this?

First, to use MySQL Connector/Python Django backend, you have to set the ENGINE setting to mysql.connector.django:
DATABASE = {
'default': {
..
'ENGINE': 'mysql.connector.django',
..
}
}
Indeed, MySQL Connector/Python does not have the init_command connection argument. I can see value in adding an option for setting the default storage engine in the Django OPTIONS though. If you really want it, I would suggest opening a feature request on http://bugs.mysql.com.
Small note that MySQL 5.6 (and if you start out, you should use this version) has storage engine set to InnoDB by default.

You need to set the entire setting:
DATABASES = {
'default': {
'NAME': "MyDatabaseName,
'ENGINE': 'django.db.backends.mysql',
'USER': "MyUsername",
'PASSWORD': "MyPassword",
'HOST': "MyHostName",
'OPTIONS': {'init_command': 'SET storage_engine=INNODB'},
}
}

django test database is not created with utf8

I am using utf-8 general case insensitive for for mysql database, but django creates a test db with latin collation
I have set this:
TEST_CHARSET="utf8_general_ci"
TEST_COLLATION="utf8_general_ci"
In the settings file, but to no avail.
What else should i do?

TEST_CHARSET and TEST_COLLATION are renamed to CHARSET and COLLATION and moved to TEST dictionary in Django 1.8:
DATABASES = {
...
'TEST': {
'CHARSET': 'utf8',
'COLLATION': 'utf8_general_ci',
}
}

in settings add:
DATABASES = {
'default': {
...
'TEST_CHARSET': "utf8",
'TEST_COLLATION': "utf8_general_ci",
}
}

Please see here: https://docs.djangoproject.com/en/1.11/ref/settings/#std:setting-DATABASE-TEST
DATABASES = {
'default': {
'ENGINE': 'django.db.backends.mysql',
'NAME': <db_name>,
'USER': <user>,
'PASSWORD': <password>,
'HOST': <host>,
'PORT': <port>,
'TEST': {
'NAME': <test_db_name>,
'CHARSET': 'utf8',
'COLLATION': 'utf8_general_ci',
},
},
}

I had the same problem and spent hours of figuring it out until noticed that
TEST_CHARSET
TEST_COLLATION
should be a part of the DATABASES, not settings.py.
It's very easy to mix them up...
https://docs.djangoproject.com/en/dev/ref/settings/#testing

As others have pointed out, you need something like this to create the database
DATABASES = {
...
'TEST': {
'CHARSET': 'utf8mb4',
'COLLATION': 'utf8mb4_unicode_ci',
}
}
But you also will want to make sure that you have something like this as well, to make sure that your tests communicate with the db with the appropriate charset.
DATABASES = {
...
'OPTIONS': {
'charset': 'utf8mb4'
}
}

Take a look at the settings file example here: https://docs.djangoproject.com/en/dev/ref/databases/#connecting-to-the-database