How to add service-specific health checks?

[Kralizek]

Currently health checks are registered in the AddServiceDefaults method that invokes a AddDefaultHealthChecks.

I now want to add service-specific health checks. Some examples:

• backend => if database is available
• frontend => if backend is reachable

What's the suggested way to do this?

Option 1

• edit AddServiceDefaults so that it doesn't invoke AddDefaultHealthChecks
• change AddDefaultHealthChecks so that it returns IHealthChecksBuilder instead of IHostApplicationBuilder
• in Program.cs, have something like

builder.AddDefaultHealthChecks()
    .AddUrlGroup(new Uri("http://api/_health"), "api");

Option 2

• in Program.cs call again the AddHealthChecks method and add own check

builder.Services.AddHealthChecks()
    .AddUrlGroup(new Uri("http://api/_health"), "api");

Considering AddHealthChecks is already called via AddServiceDefaults, does it create a conflict?

[DamianEdwards]

Option 2 is the right approach. The eShopLite sample in the aspire-samples repo has some extra custom extension methods that demonstrate this.

[Kralizek]

Slightly related. Is there a plan to have anything like a Aspire Component that registers health checks for project dependencies? In the link you provided there is a hand-crafted method.

[DamianEdwards]

See #898