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ff_engine::scanner

Trait Scanner 

Source 
pub trait Scanner:
    Send
    + Sync
    + 'static {
    // Required methods
    fn name(&self) -> &'static str;
    fn interval(&self) -> Duration;
    fn scan_partition(
        &self,
        client: &Client,
        partition: u16,
    ) -> impl Future<Output = ScanResult> + Send;

    // Provided methods
    fn filter(&self) -> &ScannerFilter { ... }
    fn sample_backlog_depth(
        &self,
        _client: &Client,
        _partition: u16,
    ) -> impl Future<Output = Option<u64>> + Send { ... }
}
Expand description

Trait for background partition scanners.

Each implementation scans one aspect of execution state (lease expiry, delayed promotion, index consistency) across all partitions at a configured interval.

Required Methods§

Source

fn name(&self) -> &'static str

Human-readable name for logging.

Source

fn interval(&self) -> Duration

How often to run a full scan across all partitions.

Source

fn scan_partition( &self, client: &Client, partition: u16, ) -> impl Future<Output = ScanResult> + Send

Scan a single partition. Called once per partition per cycle.

Provided Methods§

Source

fn filter(&self) -> &ScannerFilter

Per-consumer filter applied by execution-shaped scanners to restrict the set of candidates they act on (issue #122).

Default returns ScannerFilter::NOOP — pre-#122 behaviour. Implementations override by storing a ScannerFilter on the struct (constructed via Self::with_filter(..)) and returning &self.filter.

Source

fn sample_backlog_depth( &self, _client: &Client, _partition: u16, ) -> impl Future<Output = Option<u64>> + Send

PR-94: per-cycle gauge sample. Returns Some(depth) summed across all partitions by the scanner runner to produce a single gauge value (today only cancel_reconciler exports one, feeding ff_cancel_backlog_depth). Default: None so scanners that don’t export a gauge compile unchanged.

Runs AFTER scan_partition for the same partition within the same cycle, so implementations can reuse cached state. The trivial default implementation returns None for every partition and the runner writes nothing.

Dyn Compatibility§

This trait is not dyn compatible.

In older versions of Rust, dyn compatibility was called "object safety", so this trait is not object safe.

Implementors§