Health Checks

Emit ships separate health check packages for each provider. Each package registers a lightweight probe against the infrastructure already wired up in your DI container, so no extra connections are created.

Installation

Install only the packages that match your registered providers:

dotnet add package Emit.Kafka.HealthChecks
dotnet add package Emit.MongoDB.HealthChecks
dotnet add package Emit.EntityFrameworkCore.HealthChecks

Registration

Chain the Emit health checks into AddHealthChecks():

builder.Services.AddHealthChecks()
    .AddEmitKafka()
    .AddEmitMongoDB();

For the EF Core provider, pass your DbContext type:

builder.Services.AddHealthChecks()
    .AddEmitKafka()
    .AddEmitPostgreSQL<AppDbContext>();

Then map the endpoint:

app.MapHealthChecks("/health");

What each probe does

Method	Probe	Package
`AddEmitKafka()`	Cluster metadata request via the registered `IProducer`	`Emit.Kafka.HealthChecks`
`AddEmitMongoDB()`	`db.runCommand({ping: 1})` against the configured database	`Emit.MongoDB.HealthChecks`
`AddEmitPostgreSQL<T>()`	`CanConnectAsync()` via `IDbContextFactory<T>`	`Emit.EntityFrameworkCore.HealthChecks`

All probes are read-only and non-destructive.

Options

Every method accepts the same optional parameters:

builder.Services.AddHealthChecks()
    .AddEmitKafka(
        name: "emit-kafka",
        failureStatus: HealthStatus.Degraded,
        tags: ["messaging"],
        timeout: TimeSpan.FromSeconds(10))
    .AddEmitMongoDB(
        name: "emit-mongodb",
        failureStatus: HealthStatus.Degraded,
        tags: ["database"]);

Parameter	Default	Description
`name`	`emit-kafka` / `emit-mongodb` / `emit-postgresql`	Name shown in health check results
`failureStatus`	`Unhealthy`	Status reported on failure; use `Degraded` to avoid hard-failing readiness probes
`tags`	`["emit", "<provider>"]`	Tags for filtering checks by endpoint
`timeout`	30 s (5 s for Kafka)	Per-check timeout

Filtering by tag

Use tags to separate liveness from readiness probes in Kubernetes:

// Liveness: is the process alive?
app.MapHealthChecks("/health/live");

// Readiness: are downstream services reachable?
app.MapHealthChecks("/health/ready", new HealthCheckOptions
{
    Predicate = check => check.Tags.Contains("emit")
});