A name nothing covers raised `KeyError` in four places and
`AmbiguousDatabaseError` in a fifth, so a caller had to catch both and neither
name said what happened. `UnknownDatabaseError` is all of them, exported from
`haiku.rag.store` beside the other errors.
It subclasses `KeyError`, since selecting by name is a lookup, and prints its
message plainly rather than quoted as a missing key. Both CLIs turn it into the
same clean exit they already gave the others.
A URI-backed database is constructed with a local `db_path` nothing connects
to, and the info modal reported that, so `--db-name` on an S3 database named a
local directory. `location` reads the configuration instead, and the modal
labels it as one.
`InfoModal`'s `db_path` argument is gone: both callers passed None, so only a
test reached the branch that used it.
`sessions_for` recorded what opened from `gather`'s results, which arrive only
when it runs to completion. Cancelling it discarded them, so a database that
opened while a sibling was still pending was never recorded and `aclose` never
closed it. `return_exceptions=True` covers a failing child, not a cancelled
parent.
`_open` now registers its own session, so what opened is reachable however the
fan-out ends.
`HaikuRAG.__init__` said an omitted `db_path` uses `storage.data_dir`, which
is the last of three; and that `sources` is ignored for a single `uri`, where
it raises, since only `lancedb.databases` names databases.
The name is not the only identity leaving the configuration: results,
citations, model input and errors opening a named database carry it, while
`info`, `init` and `tag` print the location. `sources=[]` returns no search
results, but `ask` and `analyze` still answer, without evidence.
Trim the comments that still narrated a failure or an alternative to the
invariant they were there for.
One sentence for the contract, one or two more only where an invariant is not
obvious. The reasons that stay are about correctness and ownership: which
database a result belongs to, who closes what, why assembly order is the
tiebreak. The ones that go narrated how the code got here.
covers_multiple, source_names, source and reader_for replace the private
state seven modules were reading to work out how many databases they had.
The configured selection is kept intact, so entering a client twice derives
the same database rather than the last derivation.
One session field, whichever kind it is, with the covered databases derived
from it rather than kept beside it. `_single_session` returns the database a
write works on in place of ten guards that only asserted one existed, and the
single-database operations move to the session that owns them.
FederatedSession opens the databases a query covers and owns their
teardown; the client keeps the wrappers it hands out. A wrapper releases
what it built and never closes the database it borrowed.
SingleDatabaseSession owns the store, the repositories and the vacuum
machinery, so nothing above has to ask whether it has a store. The client
keeps every name callers already use.
