Module primary_tracker 

Primary Tracker - Tracks current primary node for query routing

Monitors cluster topology and maintains the current primary node information. During switchover, updates are received from the switchover coordinator to ensure queries are routed correctly.

Topology Providers

The primary tracker uses a TopologyProvider trait to abstract over different topology sources:

• HeliosDB: Uses the internal TopologyManager from the replication subsystem (feature-gated behind heliosdb-topology).
• PostgreSQL: Polls pg_stat_replication / pg_is_in_recovery() to detect primary changes (feature-gated behind postgres-topology).
• Manual/Standalone: Programmatic set/clear via API calls.

Modules

heliosdb_provider

Bridge to the HeliosDB-Lite internal TopologyManager.

Structs

PostgresNode

PostgresTopologyProvider

PostgreSQL-based topology provider.

PrimaryInfo

Primary node information

PrimaryTracker

Primary Tracker

TopologyNodeInfo

Information about a node in the cluster topology.

Enums

PrimaryChangeEvent

Primary change event

TopologyEvent

Events emitted by a topology provider.

Traits

TopologyProvider

Trait abstracting topology discovery.