Async providers with async dependencies #368
Description
It turns out that async providers currently cannot have async dependencies.
Example: in this container, both are async functions:
class Container(containers.DeclarativeContainer):
db = providers.Factory(async_db_provider)
service = providers.Singleton(async_service, db=db)Now, when in my code I request an instance of service:
service = await container.service()the expected result would be an instance of service. The actual result is its unawaited coroutine:
<coroutine object async_service at 0x7faea530fc40>
This behavior persists with Resource, Couroutine, and other providers.
Full source code to reproduce:
# Create two async providers
async def async_db_provider():
return {'db': 'ok'} # just some sample object
async def async_service(db = None):
return {'service': 'ok', 'db': db}
class Container(containers.DeclarativeContainer):
# Second provider, a singleton, depends on the first one
db = providers.Factory(async_db_provider)
service = providers.Singleton(async_service, db=db)
if __name__ == '__main__':
# Create the container
container = Container()
async def main():
try:
# Request the service
service = await container.service()
print(service) # <--- expected: instance of service
finally:
# Shutdown resources
shutdown_resources_awaitable = container.shutdown_resources()
if isawaitable(shutdown_resources_awaitable):
await shutdown_resources_awaitable
asyncio.run(main())