Add a common error for this case because it is not an error
which should increase error counter. Single error simplifies checks on
the call-site.
Signed-off-by: Evgenii Stratonikov <evgeniy@morphbits.ru>
This check should occur on the shard level, but because
blobstor components expose `Open(readOnly bool)` interface,
it is reasonable to expect an error here.
Signed-off-by: Evgenii Stratonikov <evgeniy@morphbits.ru>
1. Move compression parameters to the `shard` section.
2. Allow to use multiple sub-storage components in the blobstor.
Signed-off-by: Evgenii Stratonikov <evgeniy@nspcc.ru>
Allow to extend blobstor with more storage sub-systems. Currently
objects stored in the FSTree have empty byte slice descriptor and object
from blobovnicza tree have the same id as earlier. Each such change in
the identifier formation should be accompanied with metabase version
increase.
Signed-off-by: Evgenii Stratonikov <evgeniy@nspcc.ru>