microsoft/aspire · error · InvalidOperationException

The dashboard URL is not available.

Error message

The dashboard URL is not available.

What it means

After the app starts, GetDashboardUrlAsync looks up a resource named 'dashboard' in the application model and requires it to expose endpoints. If the model has no such resource or it implements no endpoints, no dashboard URL can be derived and this error is thrown.

Solutions

  1. Ensure the app is started (await app.StartAsync()) and wait for the dashboard resource to be created before fetching the URL.
  2. Verify the dashboard resource exists: app.Services.GetRequiredService<DistributedApplicationModel>().Resources.Any(r => r.Name == "dashboard").
  3. Re-enable the dashboard if it was disabled via configuration.
  4. Check you are running in run mode (not publish) so the dashboard resource is materialized.

Example fix

// before
var url = await app.GetDashboardUrlAsync();
// after
await app.ResourceNotifications.WaitForResourceAsync("dashboard", KnownResourceStates.Running);
var url = await app.GetDashboardUrlAsync();
Defensive patterns

Strategy: validation

Validate before calling

var model = app.Services.GetRequiredService<DistributedApplicationModel>();
var ready = model.Resources.TryGetByName("dashboard", out var r) && r is IResourceWithEndpoints;
if (!ready)
{
    // dashboard resource missing or has no endpoints; wait or bail out
}

Type guard

static bool HasDashboardResource(DistributedApplication app) =>
    app.Services.GetRequiredService<DistributedApplicationModel>()
        .Resources.TryGetByName("dashboard", out var r) && r is IResourceWithEndpoints;

Try / catch

try
{
    var url = await app.GetDashboardUrlAsync(ct);
}
catch (InvalidOperationException ex) when (ex.Message.Contains("not available"))
{
    url = null; // dashboard resource absent from the model
}

Prevention

When it happens

Trigger: Calling GetDashboardUrlAsync on an app whose DistributedApplicationModel lacks the dashboard resource (added automatically only in run mode with dashboard enabled) or whose dashboard resource has no endpoints registered.

Common situations: Calling before the model is fully built/started; custom AppHosts that suppress or rename the dashboard resource; non-Aspire execution paths (e.g. running via dotnet run without the DCP wiring).

Understand the failure class

Background: 'Could not be found', 'does not exist', 'not found in database': the resource-not-found family when an ID, slug, key, or URI lookup comes back empty — this error's family across 20 libraries.

Related errors

AI-assisted analysis of microsoft/aspire@25830f84bd (2026-09-16). Data as JSON: /api/errors/3ea0e689fa13d332. Report an issue: GitHub.

Appendix: source

Thrown at src/Aspire.Hosting.Testing/DistributedApplicationHostingTestingExtensions.cs:95

        var applicationOptions = app.Services.GetRequiredService<DistributedApplicationOptions>();
        if (applicationOptions.DisableDashboard)
        {
            throw new InvalidOperationException(Properties.Resources.DashboardDisabledExceptionMessage);
        }

        ThrowIfNotStarted(app, Properties.Resources.DashboardUrlApplicationNotStartedExceptionMessage);
        cancellationToken.ThrowIfCancellationRequested();

        await app.ResourceNotifications.WaitForResourceHealthyAsync(
            DashboardResourceName,
            WaitBehavior.StopOnResourceUnavailable,
            cancellationToken).ConfigureAwait(false);

        var applicationModel = app.Services.GetRequiredService<DistributedApplicationModel>();
        if (!applicationModel.Resources.TryGetByName(DashboardResourceName, out var resource) ||
            resource is not IResourceWithEndpoints dashboardResource)
        {
            throw new InvalidOperationException(Properties.Resources.DashboardUrlUnavailableExceptionMessage);
        }

        var httpsEndpoint = dashboardResource.GetEndpoint("https");
        var httpEndpoint = dashboardResource.GetEndpoint("http");
        var dashboardEndpoint = httpsEndpoint.Exists ? httpsEndpoint : httpEndpoint;
        if (!dashboardEndpoint.Exists)
        {
            throw new InvalidOperationException(Properties.Resources.DashboardUrlUnavailableExceptionMessage);
        }

        var dashboardUrl = await EndpointHostHelpers.GetUrlWithTargetHostAsync(dashboardEndpoint, cancellationToken).ConfigureAwait(false);
        if (string.IsNullOrEmpty(dashboardUrl))
        {
            throw new InvalidOperationException(Properties.Resources.DashboardUrlUnavailableExceptionMessage);
        }

        var browserToken = app.Services.GetRequiredService<IConfiguration>()["AppHost:BrowserToken"];
        if (!string.IsNullOrEmpty(browserToken))

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