* fix: prevent duplicate dispatcher creation race condition in invoke_global_service
Concurrent coroutines could all pass the `if key in self.dispatchers` check
before any of them wrote the result back, because `await dispatcher.start()`
yields to the event loop. This caused multiple Pulsar consumers to be created
on the same shared subscription, distributing responses round-robin and
dropping ~2/3 of them — manifesting as a permanent spinner in the Workbench UI.
Apply a double-checked asyncio.Lock in both `invoke_global_service` and
`invoke_flow_service` so only one dispatcher is ever created per service key.
* test: add concurrent-dispatch tests for race condition fix
Add asyncio.gather-based tests that verify invoke_global_service and
invoke_flow_service create exactly one dispatcher under concurrent calls,
preventing the duplicate Pulsar consumer bug.
The metadata field (list of triples) in the pipeline Metadata class
was redundant. Document metadata triples already flow directly from
librarian to triple-store via emit_document_provenance() - they don't
need to pass through the extraction pipeline.
Additionally, chunker and PDF decoder were overwriting metadata to []
anyway, so any metadata passed through the pipeline was being
discarded.
Changes:
- Remove metadata field from Metadata dataclass
(schema/core/metadata.py)
- Update all Metadata instantiations to remove metadata=[]
parameter
- Remove metadata handling from translators (document_loading,
knowledge)
- Remove metadata consumption from extractors (ontology, agent)
- Update gateway serializers and import handlers
- Update all unit, integration, and contract tests
* Changed schema for Value -> Term, majorly breaking change
* Following the schema change, Value -> Term into all processing
* Updated Cassandra for g, p, s, o index patterns (7 indexes)
* Reviewed and updated all tests
* Neo4j, Memgraph and FalkorDB remain broken, will look at once settled down
* Tech spec for graceful shutdown
* Graceful shutdown of importers/exporters
* Update socket to include graceful shutdown orchestration
* Adding tests for conditions tracked in this PR
