Database 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 it in

Import SeaOrmHealthModule alongside HealthModule:

apps/api/src/module.rs

use nest_rs::core::module;
use nest_rs::health::HealthModule;
use nest_rs::seaorm::{SeaOrmDatabaseModule, SeaOrmHealthModule, SeaOrmModule};

#[module(
    imports = [
        SeaOrmModule::for_root(None),
        SeaOrmDatabaseModule,
        SeaOrmHealthModule,
        HealthModule,
    ],
)]
pub struct AppModule;

That’s it. Importing the module registers SeaOrmHealthIndicator 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	SeaOrmHealthIndicator::db	503 while unreachable
GET /health/startup	SeaOrmHealthIndicator::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":"up","info":{"db":{"name":"db","status":"up"}},"error":{},
 "details":{"db":{"name":"db","status":"up"}}}

When the ping fails the indicator moves from info to error, the overall status switches to down, and the response is a 503. The body carries the fixed reason "check failed" — never the DbErr, which would put a DSN or an internal hostname on a routinely unauthenticated endpoint. The real error goes to the log instead: warn on nest_rs::health, with indicator, kind and error as fields. Indicators is the reference for that split; the shape itself is on Health.

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.