This project shows the use of HealthChecks, which is a middleware that shows us application status and health.

Used packages

dotnet add package AspNetCore.HealthChecks.SqlServer
dotnet add package AspNetCore.HealthChecks.UI
dotnet add package AspNetCore.HealthChecks.UI.Client
dotnet add package AspNetCore.HealthChecks.UI.InMemory.Storage

Registering and configuring the service

startup.cs - ConfigureServices

            services.AddHealthChecks()
                .AddSqlServer(connectionString: Configuration.GetConnectionString("SQLContext"),
                name: "Sql Server Instance")
                .AddCheck<CustomHealthChecks>("Custom Health Checks"); // That's where we add our custom HealthCheck


            //HealthChecks UI
            services.AddHealthChecksUI(options =>
            {
                options.SetEvaluationTimeInSeconds(5);
                options.MaximumHistoryEntriesPerEndpoint(10);
                options.AddHealthCheckEndpoint("API with Health Checks", "/health");
            })
            .AddInMemoryStorage(); 

startup.cs - Configure

            app.UseHealthChecksUI(options => {
                options.UIPath = "/dashboard";
                options.AddCustomStylesheet("Configuration/HealthChecks/HealthChecksUI.css");
            });

Creating a custom healthchecks

CustomHealthChecks.cs

  public class CustomHealthChecks : IHealthCheck
    {
        public Task<HealthCheckResult> CheckHealthAsync(HealthCheckContext context, CancellationToken cancellationToken = default)
        {
            return Task.FromResult(new HealthCheckResult(
                        status: HealthStatus.Unhealthy,
                        description: "There's something not ok."
                        ));
        }
    }

Adding a new personalized style file to format HealthCheckUI

HealthChecksUI.css

:root {
    --bgMain: #fff; /* background color */
    --fcBase: #000; /* font color */
    --bgMenuActive: #2f2f2f; /* background color of active menu item */
    --bcMenuActive: #fffb00; /* border color of active menu item */
    --primaryColor: #5789e0; /* primary color */
    --secondaryColor: #5789e0; /* secondary color */
    --bgMenuActive: #5789e0; /* background color of menu item when active */
    --bgButton: #5789e0; /* background color of button */
    --logoImageUrl: url('https://cdn.jsdelivr.net/gh/devicons/devicon/icons/dotnetcore/dotnetcore-original.svg'); /* logo image url */
    --bgAside: var(--primaryColor); /* background color of aside */
    --bgTable: #99b8ee; /* background color of table */
    --bgTableSecondary: #99b8ee; /* secondary background color of table */

The healthcheck will be accessed through '/dashboard' on the URL. E.g. localhost:44304/dashboard

For more information, check on at https://github.com/Xabaril/AspNetCore.Diagnostics.HealthChecks
For a user tutorial in portuguese, check on at https://balta.io/blog/aspnet-health-check