fn augment(
lowered: LirDataflowDescription,
sources: &BTreeMap<GlobalId, PersistSource>,
sinks: &BTreeMap<GlobalId, CollectionMetadata>,
) -> Result<RenderDataflowDescription<CollectionMetadata>>Expand description
Convert a lowered DataflowDescription<Plan, ()> into the
<RenderPlan, CollectionMetadata> form expected by the compute protocol.
Mirrors compute-client’s Instance::create_dataflow: each object’s LirRelationExpr
is flattened into a RenderPlan, and every source import is augmented with the
storage CollectionMetadata needed by the compute instance to read it. The
per-id PersistSource supplies the metadata and the exclusive upper telling
the compute instance up to which timestamp the shard’s data is available.