scadaproj/ZB.MOM.WW.Telemetry/tests/ZB.MOM.WW.Telemetry.Tests/MapZbMetricsTests.cs

using Microsoft.AspNetCore.Builder;
using Microsoft.AspNetCore.Hosting;
using Microsoft.Extensions.Hosting;
using ZB.MOM.WW.Telemetry;

namespace ZB.MOM.WW.Telemetry.Tests;

public sealed class MapZbMetricsTests
{
    [Fact]
    public async Task MapZbMetrics_ServesPrometheusEndpoint()
    {
        var builder = WebApplication.CreateBuilder();
        builder.WebHost.UseUrls("http://127.0.0.1:0");
        builder.AddZbTelemetry(o =>
        {
            o.ServiceName = "t";
            o.Exporter = ZbExporter.Prometheus;
            o.Meters = ["Test.Meter"];
        });

        await using var app = builder.Build();
        app.MapZbMetrics();

        await app.StartAsync();

        var address = app.Urls.First();
        using var client = new HttpClient { BaseAddress = new Uri(address) };

        var response = await client.GetAsync("/metrics");

        Assert.Equal(System.Net.HttpStatusCode.OK, response.StatusCode);
        Assert.NotNull(response.Content.Headers.ContentType);
        Assert.Equal("text/plain", response.Content.Headers.ContentType!.MediaType);

        await app.StopAsync();
    }
}