Validate that the localtest version is new enough for the app on star…

…tup (#1007)

src/Altinn.App.Core/Configuration/GeneralSettings.cs

@@ -34,6 +34,11 @@ public class GeneralSettings
     /// </summary>
     public string HostName { get; set; } = "local.altinn.cloud";
 
+    /// <summary>
+    /// Gets or sets a value indicating whether to disable localtest validation on startup.
+    /// </summary>
+    public bool DisableLocaltestValidation { get; set; }
+
     /// <summary>
     /// The externally accesible base url for the app with trailing /
     /// </summary>

src/Altinn.App.Core/Extensions/ServiceCollectionExtensions.cs

@@ -26,6 +26,7 @@
 using Altinn.App.Core.Infrastructure.Clients.Profile;
 using Altinn.App.Core.Infrastructure.Clients.Register;
 using Altinn.App.Core.Infrastructure.Clients.Storage;
+using Altinn.App.Core.Internal;
 using Altinn.App.Core.Internal.App;
 using Altinn.App.Core.Internal.AppModel;
 using Altinn.App.Core.Internal.Auth;
@@ -176,6 +177,9 @@ IWebHostEnvironment env
         services.Configure<FrontEndSettings>(configuration.GetSection(nameof(FrontEndSettings)));
         services.Configure<PdfGeneratorSettings>(configuration.GetSection(nameof(PdfGeneratorSettings)));
 
+        if (env.IsDevelopment())
+            services.AddLocaltestValidation(configuration);
+
         AddValidationServices(services, configuration);
         AddAppOptions(services);
         AddExternalApis(services);

src/Altinn.App.Core/Internal/LocaltestValidation.cs

@@ -0,0 +1,216 @@
+using System.Globalization;
+using System.Net;
+using System.Threading.Channels;
+using Altinn.App.Core.Configuration;
+using Microsoft.Extensions.Configuration;
+using Microsoft.Extensions.DependencyInjection;
+using Microsoft.Extensions.Hosting;
+using Microsoft.Extensions.Logging;
+using Microsoft.Extensions.Options;
+
+namespace Altinn.App.Core.Internal;
+
+internal static class LocaltestValidationDI
+{
+    public static IServiceCollection AddLocaltestValidation(
+        this IServiceCollection services,
+        IConfiguration configuration
+    )
+    {
+        if (configuration.GetValue<bool>("GeneralSettings:DisableLocaltestValidation"))
+            return services;
+        services.AddHostedService<LocaltestValidation>();
+        return services;
+    }
+}
+
+internal sealed class LocaltestValidation : BackgroundService
+{
+    private const string ExpectedHostname = "local.altinn.cloud";
+
+    private readonly ILogger<LocaltestValidation> _logger;
+    private readonly IHttpClientFactory _httpClientFactory;
+    private readonly IOptionsMonitor<GeneralSettings> _generalSettings;
+    private readonly IOptionsMonitor<PlatformSettings> _platformSettings;
+    private readonly IHostApplicationLifetime _lifetime;
+    private readonly TimeProvider _timeProvider;
+    private readonly Channel<VersionResult> _resultChannel;
+
+    internal IAsyncEnumerable<VersionResult> Results => _resultChannel.Reader.ReadAllAsync();
+
+    public LocaltestValidation(
+        ILogger<LocaltestValidation> logger,
+        IHttpClientFactory httpClientFactory,
+        IOptionsMonitor<GeneralSettings> generalSettings,
+        IOptionsMonitor<PlatformSettings> platformSettings,
+        IHostApplicationLifetime lifetime,
+        TimeProvider? timeProvider = null
+    )
+    {
+        _logger = logger;
+        _httpClientFactory = httpClientFactory;
+        _generalSettings = generalSettings;
+        _platformSettings = platformSettings;
+        _lifetime = lifetime;
+        _timeProvider = timeProvider ?? TimeProvider.System;
+        _resultChannel = Channel.CreateBounded<VersionResult>(
+            new BoundedChannelOptions(10) { FullMode = BoundedChannelFullMode.DropWrite }
+        );
+    }
+
+    private void Exit()
+    {
+        _lifetime.StopApplication();
+    }
+
+    protected override async Task ExecuteAsync(CancellationToken stoppingToken)
+    {
+        try
+        {
+            var settings = _generalSettings.CurrentValue;
+            if (settings.DisableLocaltestValidation)
+                return;
+
+            var configuredHostname = settings.HostName;
+            if (configuredHostname != ExpectedHostname)
+                return;
+
+            while (!stoppingToken.IsCancellationRequested)
+            {
+                var result = await Version();
+                try
+                {
+                    switch (result)
+                    {
+                        case VersionResult.Ok { Version: var version }:
+                        {
+                            _logger.LogInformation("Localtest version: {Version}", version);
+                            if (version >= 1)
+                                return;
+                            _logger.LogError(
+                                "Localtest version is not supported for this version of the app backend. Update your local copy of localtest."
+                                    + " Version found: '{Version}'. Shutting down..",
+                                version
+                            );
+                            Exit();
+                            return;
+                        }
+                        case VersionResult.ApiNotFound:
+                        {
+                            _logger.LogError(
+                                "Localtest version may be outdated, as we failed to probe {HostName} API for version information."
+                                    + " Is localtest running? Do you have a recent copy of localtest? Shutting down..",
+                                ExpectedHostname
+                            );
+                            Exit();
+                            return;
+                        }
+                        case VersionResult.ApiNotAvailable { Error: var error }:
+                            _logger.LogWarning(
+                                "Localtest API could not be reached, is it running? Trying again soon.. Error: '{Error}'. Trying again soon..",
+                                error
+                            );
+                            break;
+                        case VersionResult.UnhandledStatusCode { StatusCode: var statusCode }:
+                            _logger.LogError(
+                                "Localtest version endpoint returned unexpected status code: '{StatusCode}'. Trying again soon..",
+                                statusCode
+                            );
+                            break;
+                        case VersionResult.UnknownError { Exception: var ex }:
+                            _logger.LogError(ex, "Error while trying to fetch localtest version. Trying again soon..");
+                            break;
+                        case VersionResult.AppShuttingDown:
+                            return;
+                    }
+                }
+                finally
+                {
+                    if (!_resultChannel.Writer.TryWrite(result))
+                        _logger.LogWarning("Couldn't log result to channel");
+                }
+                await Task.Delay(TimeSpan.FromSeconds(5), _timeProvider, stoppingToken);
+            }
+        }
+        catch (OperationCanceledException) { }
+        finally
+        {
+            if (!_resultChannel.Writer.TryComplete())
+                _logger.LogWarning("Couldn't close result channel");
+        }
+    }
+
+    internal abstract record VersionResult
+    {
+        // Localtest is running, and we got a version number, which means this is a version of localtest that has
+        // the new version endpoint.
+        public sealed record Ok(int Version) : VersionResult;
+
+        public sealed record InvalidVersionResponse(string Repsonse) : VersionResult;
+
+        // Whatever listened on "local.altinn.cloud:80" responded with a 404
+        public sealed record ApiNotFound() : VersionResult;
+
+        // The request timed out. Note that there may be multiple variants of timeouts.
+        public sealed record Timeout() : VersionResult;
+
+        // Could not connect to "local.altinn.cloud:80", a server might not be listening on that address
+        // or it might be a network issue
+        public sealed record ApiNotAvailable(HttpRequestError Error) : VersionResult;
+
+        // Request was cancelled because the application is shutting down
+        public sealed record AppShuttingDown() : VersionResult;
+
+        // The localtest endpoint returned an unexpected statuscode
+        public sealed record UnhandledStatusCode(HttpStatusCode StatusCode) : VersionResult;
+
+        // Unhandled error
+        public sealed record UnknownError(Exception Exception) : VersionResult;
+    }
+
+    private async Task<VersionResult> Version()
+    {
+        using var cts = new CancellationTokenSource(TimeSpan.FromSeconds(5), _timeProvider);
+        using var linkedCts = CancellationTokenSource.CreateLinkedTokenSource(cts.Token, _lifetime.ApplicationStopping);
+        var cancellationToken = linkedCts.Token;
+        try
+        {
+            using var client = _httpClientFactory.CreateClient();
+
+            var baseUrl = new Uri(_platformSettings.CurrentValue.ApiStorageEndpoint).GetLeftPart(UriPartial.Authority);
+            var url = $"{baseUrl}/Home/Localtest/Version";
+
+            using var response = await client.GetAsync(url, cancellationToken);
+            switch (response.StatusCode)
+            {
+                case HttpStatusCode.OK:
+                    var versionStr = await response.Content.ReadAsStringAsync(cancellationToken);
+                    if (!int.TryParse(versionStr, CultureInfo.InvariantCulture, out var version))
+                        return new VersionResult.InvalidVersionResponse(versionStr);
+                    return new VersionResult.Ok(version);
+                case HttpStatusCode.NotFound:
+                    return new VersionResult.ApiNotFound();
+                default:
+                    return new VersionResult.UnhandledStatusCode(response.StatusCode);
+            }
+        }
+        catch (OperationCanceledException)
+        {
+            if (_lifetime.ApplicationStopping.IsCancellationRequested)
+                return new VersionResult.AppShuttingDown();
+
+            return new VersionResult.Timeout();
+        }
+        catch (HttpRequestException ex)
+        {
+            if (_lifetime.ApplicationStopping.IsCancellationRequested)
+                return new VersionResult.AppShuttingDown();
+
+            return new VersionResult.ApiNotAvailable(ex.HttpRequestError);
+        }
+        catch (Exception ex)
+        {
+            return new VersionResult.UnknownError(ex);
+        }
+    }
+}

test/Altinn.App.Api.Tests/Program.cs

@@ -57,6 +57,7 @@
 );
 builder.Configuration.GetSection("MetricsSettings:Enabled").Value = "false";
 builder.Configuration.GetSection("AppSettings:UseOpenTelemetry").Value = "true";
+builder.Configuration.GetSection("GeneralSettings:DisableLocaltestValidation").Value = "true";
 
 ConfigureServices(builder.Services, builder.Configuration);
 ConfigureMockServices(builder.Services, builder.Configuration);

test/Altinn.App.Core.Tests/Altinn.App.Core.Tests.csproj

@@ -57,6 +57,8 @@
       <PrivateAssets>all</PrivateAssets>
       <IncludeAssets>runtime; build; native; contentfiles; analyzers; buildtransitive</IncludeAssets>
     </PackageReference>
+    <PackageReference Include="WireMock.Net" Version="1.6.11" />
+    <PackageReference Include="System.Linq.Async" Version="6.0.1" />
   </ItemGroup>
 
   <ItemGroup>