w4c-workflows-api/w4c-workflows-api.Tests/WorkflowQuotaControllerTests.cs

using Microsoft.AspNetCore.Http;
using Microsoft.AspNetCore.Mvc;
using Microsoft.Extensions.Configuration;
using w4c_workflows.Controllers;
using w4c_workflows.Data;
using w4c_workflows.Services.Quota;
using Xunit;

namespace w4c_workflows.Tests;

/// <summary>
/// P1-14: resetting a tenant's monthly execution counter is a platform-admin
/// action. A tenant must not be able to zero its own quota, and the gate must
/// fail closed when <c>Workflows:AdminApiKey</c> is not configured at all.
/// </summary>
[Collection("WorkflowsPostgres")]
public class WorkflowQuotaControllerTests
{
    private readonly WorkflowsPostgresFixture _fixture;

    public WorkflowQuotaControllerTests(WorkflowsPostgresFixture fixture) => _fixture = fixture;

    private static string Tenant() => "q" + Guid.NewGuid().ToString("N")[..12];

    private static IConfiguration Config(string? adminKey)
        => new ConfigurationBuilder()
            .AddInMemoryCollection(new Dictionary<string, string?>
            {
                ["Workflows:AdminApiKey"] = adminKey,
            })
            .Build();

    private static WorkflowQuotaController Controller(
        WorkflowQuotaService quota, string tenantId, string? adminKey, string? providedKey)
    {
        var http = new DefaultHttpContext();
        http.Items["TenantId"] = tenantId;
        if (providedKey != null)
            http.Request.Headers["X-Admin-Key"] = providedKey;

        return new WorkflowQuotaController(quota, Config(adminKey))
        {
            ControllerContext = new ControllerContext { HttpContext = http },
        };
    }

    [Fact]
    public async Task Reset_is_forbidden_when_no_admin_key_is_configured()
    {
        var tenantId = Tenant();
        await using var db = _fixture.CreateContext();

        var result = await Controller(
            QuotaTestData.Service(db), tenantId, adminKey: null, providedKey: "anything").Reset(default);

        var forbidden = Assert.IsType<ObjectResult>(result);
        Assert.Equal(StatusCodes.Status403Forbidden, forbidden.StatusCode);
    }

    [Fact]
    public async Task Reset_is_forbidden_with_the_wrong_admin_key()
    {
        var tenantId = Tenant();
        await using var db = _fixture.CreateContext();

        var result = await Controller(
            QuotaTestData.Service(db), tenantId, adminKey: "correct-secret", providedKey: "wrong-secret")
            .Reset(default);

        var forbidden = Assert.IsType<ObjectResult>(result);
        Assert.Equal(StatusCodes.Status403Forbidden, forbidden.StatusCode);
    }

    [Fact]
    public async Task Reset_with_the_admin_key_zeroes_the_counter()
    {
        var tenantId = Tenant();
        await using var db = _fixture.CreateContext();
        var quota = QuotaTestData.Service(db, new WorkflowQuotaOptions { RunsPerMonth = 10 });
        Assert.True(await quota.TryReserveAsync(tenantId));
        Assert.Equal(1, (await quota.GetAsync(tenantId)).Used);

        var controller = Controller(quota, tenantId, adminKey: "correct-secret", providedKey: "correct-secret");

        var result = Assert.IsType<OkObjectResult>(await controller.Reset(default));
        var snapshot = Assert.IsType<WorkflowQuota>(result.Value);
        Assert.Equal(0, snapshot.Used);
        Assert.Equal(0, (await quota.GetAsync(tenantId)).Used);
    }
}