[
https://issues.apache.org/jira/browse/SLING-4461?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=14363116#comment-14363116
]
Marius Petria commented on SLING-4461:
--------------------------------------
bq. So, with filters we can cover everything from most narrow requirements to
broadest possible openness as supported by the API.
Right, however the concept of defaults becomes a bit twisted: defaults are not
really fallbacks but proper sub service names. For example in an application
that always uses ServiceUserMapped to ensure proper ordering, an administrator
cannot freely add a default in order to satisfy all subServices for a bundle,
so the utility of defaults is zero. They are no longer an implementation
(configuration) detail, that permit an arbitrary number of subServices to be
satisfied with a single configuration. The nonexisting serviceName is actually
a "special" (empty) subServiceName that is part of the contract, and can be
referenced by developers. As you said we can make also the global fallback a
part of the contract, but I cannot see an usecase for specifying a dependency
on a global default.
I think that if we accept that default names (non existing subServiceName
property, default property) are part of the contract, then we do not need to
change anything, we just have a not so useful notion of defaults.
> Remove fallbacks for service users resolution
> ---------------------------------------------
>
> Key: SLING-4461
> URL: https://issues.apache.org/jira/browse/SLING-4461
> Project: Sling
> Issue Type: Improvement
> Components: Service User Mapper
> Reporter: Marius Petria
>
> ServiceUserMapperImpl has several levels of fallback for service user
> resolution (fallback to bundle default, or to global default). While this
> offers a lot of flexibility, it introduces non-determinism in a security
> feature. If defaults are set, it can happen (especially at startup) that code
> is executed using different serviceUsers, e.g. a component can execute using
> the bundle default or global default until its specific subService is
> available, and it can be easily imagined how this can cause subtle errors.
--
This message was sent by Atlassian JIRA
(v6.3.4#6332)
