test_config.py

"""
this file will be imported by the __init__.py in the same directory
It will first try to read from the environment variables, so
`export SECRET_KEY='yourkey` would override the settings below.
Also `export DATABASE_URL='postgresql://usernam:password@database.example.com:5432/your_db'`

NOTE: you could also do something like this, having more environment variables/

SQLALCHEMY_DATABASE_URI = 
        f"postgresql://{os.environ['DATABASE_USERNAME']}:{os.environ['DATABASE_PASSWORD']}@{os.environ['DATABASE_HOST']}:{os.environ['DATABASE_PORT']}/{os.environ['DATABASE_NAME']}"

Below, I do a variation. 

NOTE: this could also be created as on object, and read in the __init__.py  with 
    `app.config.from_object(Config)
"""





import os

# DATABASE_USERNAME = os.environ.get('DATABASE_USERNAME') or 'postgres'
# DATABASE_PASSWORD = os.environ.get('DATABASE_PASSWORD') or ''
# DATABASE_HOST = os.environ.get('DATABASE_HOST') or 'localhost'
# DATABASE_PORT = os.environ.get('DATABASE_PORT') or '5432'
DATABASE_NAME = 'test_moody'







database_url_string = "sqlite:///test.db"

# put it all together
SQLALCHEMY_DATABASE_URI = os.environ.get(
    'DATABASE_URL') or database_url_string

# other settings from examples.
SQLALCHEMY_TRACK_MODIFICATIONS = False
SQLALCHEMY_ECHO = False


TESTING = True

SECRET_KEY = os.environ.get('SECRET_KEY')
WTF_CSRF_SECRET_KEY = os.environ.get('WTF_CSRF_SECRET_KEY')