id()
id() : string
The id the provider registers under, as it appears in configuration.
Returns
string —A short lowercase token such as "s3" or "sftp".
Builds a storage provider a submodule contributes.
A provider is registered as a factory rather than as an instance because building one reads configuration and can fail: a missing bucket, credentials that do not resolve, an endpoint URL with no host. Deferring that until the provider is actually selected keeps a misconfigured optional provider from taking the container down at compile time.