Struct SnapshotCache 

pub struct SnapshotCache { /* private fields */ }

A cache that holds monitoring snapshots and refreshes them periodically.

When PrometheusMetrics are attached, the cache also updates Prometheus gauges during each refresh, keeping metric values in lockstep with the snapshot data. This means the /metrics handler never needs to compute values — it only gathers and encodes.

Implementations

impl SnapshotCache

pub fn new( refresh_interval: Duration, server_source: Option<Arc<dyn ServerMonitoring + Send + Sync>>, sv2_clients_source: Option<Arc<dyn Sv2ClientsMonitoring + Send + Sync>>, ) -> Self

Create a new snapshot cache with the given refresh interval.

Arguments

• refresh_interval - How often to refresh the cache (e.g., 15 seconds)
• server_source - Optional server monitoring trait object
• sv2_clients_source - Optional Sv2 clients monitoring trait object

pub fn with_sv1_clients_source( self, sv1_source: Arc<dyn Sv1ClientsMonitoring + Send + Sync>, ) -> Self

Add SV1 monitoring source (for Tproxy)

pub fn with_metrics(self, metrics: PrometheusMetrics) -> Self

Attach (or replace) Prometheus metrics so they are updated during each refresh().

This is called once in MonitoringServer::new and may be called again in with_sv1_monitoring which re-creates the metrics with SV1 gauges enabled.

pub fn get_snapshot(&self) -> MonitoringSnapshot

Get the current snapshot.

This is a fast read that does NOT acquire any business logic locks. The returned snapshot may be up to refresh_interval old.

pub fn refresh(&self)

Refresh the cache by reading from the data sources.

This method DOES acquire the business logic locks (via the trait methods), but it’s only called periodically by a background task, not on every request.

When Prometheus metrics are attached, they are updated atomically alongside the snapshot — eliminating any gap where metrics could be missing or stale relative to the snapshot data.

pub fn refresh_interval(&self) -> Duration

Get the refresh interval

Trait Implementations

impl Clone for SnapshotCache

fn clone(&self) -> Self

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.