Health

The readiness probe should fail when the database is unreachable. NestRS ships a SeaORM-backed indicator that runs DatabaseConnection::ping and plugs straight into nest-rs-health’s indicator registry — no glue code, no probe handler to write.

Wire the indicator

Import DatabaseHealthModule alongside HealthModule:

src/module.rs

use nest_rs_health::HealthModule;
use nest_rs_seaorm::DatabaseHealthModule;

#[module(
    imports = [
        DatabaseModule::for_root(None),
        HealthModule,
        DatabaseHealthModule,
    ],
)]
pub struct AppModule;

That’s it. Importing the module registers DbHealthIndicator as both a readiness and a startup indicator — HealthModule discovers them through the inventory seam and mounts the probes automatically.

What gets probed

Two endpoints exit the box with the database wired in:

Endpoint	Indicator runs	Failure
GET /health/ready	DbHealthIndicator::db	503 while unreachable
GET /health/startup	DbHealthIndicator::db_ready	503 until first ping succeeds

The liveness probe (GET /health/live) deliberately does not depend on the database — a brief DB outage should not kill the pod.

A passing probe

curl -s http://localhost:3000/health/ready

{
  "status": "ok",
  "details": {
    "db": { "status": "up" }
  }
}

A failure response surfaces the typed DbErr as the error field on the failing indicator, and the overall status switches to down with a 503. The same shape across every indicator means a single dashboard template covers them all.

Going further

• Database — the slice the indicator hangs off.
• Repo and executor — the DatabaseConnection the indicator pings.
• Health — the indicator registry, the probe endpoints, custom indicators for other dependencies.