Function engine_from_config

lib/sqlalchemy/engine/create.py:780–822

Create a new Engine instance using a configuration dictionary. The dictionary is typically produced from a config file. The keys of interest to ``engine_from_config()`` should be prefixed, e.g. ``sqlalchemy.url``, ``sqlalchemy.echo``, etc. The 'prefix' argument indicates the prefi

(
    configuration: Dict[str, Any], prefix: str = "sqlalchemy.", **kwargs: Any
)

def engine_from_config(
    configuration: Dict[str, Any], prefix: str = "sqlalchemy.", **kwargs: Any
) -> Engine:
    """Create a new Engine instance using a configuration dictionary.

    The dictionary is typically produced from a config file.

    The keys of interest to ``engine_from_config()`` should be prefixed, e.g.
    ``sqlalchemy.url``, ``sqlalchemy.echo``, etc.  The 'prefix' argument
    indicates the prefix to be searched for.  Each matching key (after the
    prefix is stripped) is treated as though it were the corresponding keyword
    argument to a :func:`_sa.create_engine` call.

    The only required key is (assuming the default prefix) ``sqlalchemy.url``,
    which provides the :ref:`database URL <database_urls>`.

    A select set of keyword arguments will be "coerced" to their
    expected type based on string values.    The set of arguments
    is extensible per-dialect using the ``engine_config_types`` accessor.

    :param configuration: A dictionary (typically produced from a config file,
        but this is not a requirement).  Items whose keys start with the value
        of 'prefix' will have that prefix stripped, and will then be passed to
        :func:`_sa.create_engine`.

    :param prefix: Prefix to match and then strip from keys
        in 'configuration'.

    :param kwargs: Each keyword argument to ``engine_from_config()`` itself
        overrides the corresponding item taken from the 'configuration'
        dictionary.  Keyword arguments should *not* be prefixed.

    """

    options = {
        key[len(prefix) :]: configuration[key]
        for key in configuration
        if key.startswith(prefix)
    }
    options["_coerce_config"] = True
    options.update(kwargs)
    url = options.pop("url")
    return create_engine(url, **options)


@overload