Trait SplitPlanner 

pub trait SplitPlanner: Send {
    // Required methods
    fn fingerprint(&self) -> String;
    fn plan(
        &mut self,
        ctx: PlanContext<'_>,
    ) -> Result<SplitPlan, CoordinationError>;
}

Source-provided work enumerator, run only on the fleet’s elected leader — at job start and again on the replan interval while the plan is Open.

Every worker presents an equivalent planner at SplitCoordinator::start; whichever instance holds leadership uses its own copy. plan may block on real I/O (an object-store LIST, an index query) — backends call it off their async loop.

Required Methods

fn fingerprint(&self) -> String

Cheap, deterministic job identity, derived from configuration, never from the enumeration itself. Every worker joining the job must present a byte-equal fingerprint or be rejected as Fatal — divergent configurations can never interpret the same split table two ways.

fn plan(&mut self, ctx: PlanContext<'_>) -> Result<SplitPlan, CoordinationError>

Enumerate the current work. Idempotency contract: unchanged work yields the same SplitIds, so re-emitting already-planned splits is a cheap store-side no-op.

Dyn Compatibility

This trait is dyn compatible.

In older versions of Rust, dyn compatibility was called "object safety".

Implementors