def add_databases_to_app(app: FastAPI,
dbs: Dict[str, DatabaseDefinition]) -> FastAPI:
"""Add instances of :class:`Database` as attribute of app.
For each database as defined in the ``config.yml`` as external-resource,
create a :class:`Database` instance with defined parameters, add this
instance to the ``app.databases``-attribute and add ``startup`` and
``shutdown`` handlers to connect / disconnect to the database on
app-startup / app-shutdown.
Parameters:
app: the app to add the database definitions to.
dbs: the databases to add to the app.
Returns:
modified app containing the attribute app.databases and event handler
for startup and shutdown for the databases.
"""
for _, db_definition in dbs.items():
database = Database(dsn=db_definition.dsn,
logger=app.logger,
min_size=db_definition.min_size,
max_size=db_definition.max_size)
app.add_event_handler('startup', database.connect)
app.add_event_handler('shutdown', database.disconnect)
try:
app.databases.update({db_definition.name: database})
except AttributeError:
app.databases = {db_definition.name: database}
return app
def make_app(
config_path: Path,
version: str,
endpoints: List[Endpoint],
enable_middlewares: List[str],
additional_middlewares: list,
) -> FastAPI:
"""Create app with endpoints and middlewares.
App is configured using the config of the service and defined
environment-variables.
Also logger is configured and default endpoints and additional endpoints
added.
Same for middlewares.
Note:
An app created by this function has additional attributes:
* ``app.logger``
* ``app.config``
* ``app.databases``
* ``app.services``
* ``app.mode``
Parameters:
config_path: the path for the config file to use for the app.
version: current version of the service, should be ``__version__``
variable inside the module ``app`` of your service.
endpoints: the endpoints to include to the app.
enable_middlewares: list of the middlewares to add.
additional_middlewares: list of non default middlewares to add to the
app.
Returns:
the created app.
"""
# load the config and environment-variables for the service and
# combine these information to initialize the app
config = collect_config_definition(config_path=config_path)
# update mode and logger-definitions with environment-variables if defined
# ATTENTION: the environment-variable has the prefix of the servicename
config = update_config(
env_vars=config.available_environment_variables.env_vars,
external_resources_env_vars=(
config.available_environment_variables.external_resources_env_vars
),
rules_env_vars=config.available_environment_variables.rules_env_vars,
config=config,
model=Config,
)
# convert config-attribute types if necessary
config.logger.path = Path(config.logger.path)
config.service.readme = Path(config.service.readme)
# initialize the app, add combined configuration, mode and logger
app = FastAPI(
title=f'{config.service.name} [{config.service.mode.upper()}]',
description=config.service.readme.read_text(),
version=version,
)
# add additional attributes to the app like the config and the runtime-mode
app.config = config
app.mode = config.service.mode
# Set the logging-configuration
app.logger = customize_logging(
config.logger.path / config.logger.filename.format(mode=app.mode),
level=config.logger.level,
retention=config.logger.retention,
rotation=config.logger.rotation,
_format=config.logger.format
)
# if dependencies for external databases are defined in the config, add
# these database-definitions to the app
if config.external_resources.databases:
app = add_databases_to_app(
app,
dbs=config.external_resources.databases
)
else:
app.databases = {}
# if dependencies for external services are defined in the config, add
# these service-definitions to the app
if config.external_resources.services:
app = add_services_to_app(
app,
services=config.external_resources.services
)
else:
app.services = {}
# add default endpoints if defined in the config
endpoints = add_default_endpoints(endpoints=endpoints, config=app.config)
# include defined routers and middlewares to the app
return include_endpoints_and_middlewares_to_app(
app=app,
endpoints=endpoints,
enable_middlewares=enable_middlewares,
additional_middlewares=additional_middlewares
)
