natsdotnet/tests/NATS.Server.JetStream.Tests/JetStreamApiProtocolIntegrationTests.cs

using Microsoft.Extensions.Logging.Abstractions;
using NATS.Client.Core;
using NATS.Server.Configuration;

namespace NATS.Server.JetStream.Tests;

public class JetStreamApiProtocolIntegrationTests
{
    [Fact]
    public async Task Js_api_request_over_pub_reply_returns_response_message()
    {
        await using var server = await ServerFixture.StartJetStreamEnabledAsync();
        var response = await server.RequestAsync("$JS.API.INFO", "{}", timeoutMs: 1000);

        response.ShouldContain("\"error\"");
    }
}

internal sealed class ServerFixture : IAsyncDisposable
{
    private readonly NatsServer _server;
    private readonly CancellationTokenSource _cts;

    private ServerFixture(NatsServer server, CancellationTokenSource cts)
    {
        _server = server;
        _cts = cts;
    }

    public static async Task<ServerFixture> StartJetStreamEnabledAsync()
    {
        var options = new NatsOptions
        {
            Host = "127.0.0.1",
            Port = 0,
            JetStream = new JetStreamOptions
            {
                StoreDir = Path.Combine(Path.GetTempPath(), $"nats-js-proto-{Guid.NewGuid():N}"),
                MaxMemoryStore = 1024 * 1024,
                MaxFileStore = 10 * 1024 * 1024,
            },
        };

        var server = new NatsServer(options, NullLoggerFactory.Instance);
        var cts = new CancellationTokenSource();
        _ = server.StartAsync(cts.Token);
        await server.WaitForReadyAsync();

        return new ServerFixture(server, cts);
    }

    public async Task<string> RequestAsync(string subject, string payload, int timeoutMs)
    {
        await using var conn = new NatsConnection(new NatsOpts { Url = $"nats://127.0.0.1:{_server.Port}" });
        await conn.ConnectAsync();

        using var timeout = new CancellationTokenSource(TimeSpan.FromMilliseconds(timeoutMs));
        var response = await conn.RequestAsync<string, string>(subject, payload, cancellationToken: timeout.Token);
        return response.Data ?? string.Empty;
    }

    public async ValueTask DisposeAsync()
    {
        await _cts.CancelAsync();
        _server.Dispose();
        _cts.Dispose();
    }
}