Extra Database Settings

Deeper SQLAlchemy Integration

It is possible to tweak the database connection information using the parameters exposed by SQLAlchemy. In the Database edit view, you can edit the Extra field as a JSON blob.

This JSON string contains extra configuration elements. The engine_params object gets unpacked into the sqlalchemy.create_engine call, while the metadata_params get unpacked into the sqlalchemy.MetaData call. Refer to the SQLAlchemy docs for more information.

Schemas

Databases like Postgres and Redshift use the schema as the logical entity on top of the database. For Superset to connect to a specific schema, you can set the schema parameter in the Edit Tables form (Sources > Tables > Edit record).

External Password Store for SQLAlchemy Connections

Superset can be configured to use an external store for database passwords. This is useful if you a running a custom secret distribution framework and do not wish to store secrets in Superset’s meta database.

Example: Write a function that takes a single argument of type sqla.engine.url and returns the password for the given connection string. Then set SQLALCHEMY_CUSTOM_PASSWORD_STORE in your config file to point to that function.

def example_lookup_password(url):
    secret = <<get password from external framework>>
    return 'secret'
SQLALCHEMY_CUSTOM_PASSWORD_STORE = example_lookup_password

A common pattern is to use environment variables to make secrets available. SQLALCHEMY_CUSTOM_PASSWORD_STORE can also be used for that purpose.

def example_password_as_env_var(url):
# assuming the uri looks like
# mysql://localhost?superset_user:{SUPERSET_PASSWORD}
return url.password.format(os.environ)
SQLALCHEMY_CUSTOM_PASSWORD_STORE = example_password_as_env_var

SSL Access to Databases

You can use the Extra field in the Edit Databases form to configure SSL:

{
    "metadata_params": {},
    "engine_params": {
          "connect_args":{
              "sslmode":"require",
              "sslrootcert": "/path/to/my/pem"
        }
     }
}