feat(operations): add capacity and resilience gates (#18)

tests/FinalFactory.Rendezvous.Tests/Client/RendezvousClientIntegrationTests.cs

@@ -1,3 +1,6 @@
+using System.Diagnostics;
+using System.Net;
+using System.Net.Sockets;
 using FinalFactory.Rendezvous.Client;
 using FinalFactory.Rendezvous.Contracts;
 using FinalFactory.Rendezvous.Server.Abuse;
@@ -19,6 +22,49 @@ namespace FinalFactory.Rendezvous.Tests.Client;
 
 public sealed class RendezvousClientIntegrationTests
 {
+    [Fact]
+    public async Task RestartReturnsTypedUnavailabilityThenAllowsHostReregistration()
+    {
+        int port = ReserveTcpPort();
+        string address = $"http://127.0.0.1:{port}";
+        using HttpClient client = new() { BaseAddress = new Uri(address) };
+        RendezvousClientOptions noRetry = new()
+        {
+            MaximumSafeRetries = 0,
+            RequestTimeout = TimeSpan.FromSeconds(1),
+        };
+        ClientTestHost first = await ClientTestHost.StartAsync(address);
+        RendezvousPublisherClient publisher = new(client, noRetry);
+        RendezvousClientResult<PublishedSession> registered = await publisher.RegisterAsync(
+            CreateRegistration(100),
+            first.PublisherCredential);
+        PublishedSession initialSession = AssertSuccess(registered);
+        BindPresence(first, initialSession, 41_100);
+        RendezvousSessionBrowserClient browser = new(client, noRetry);
+        BrowseSessionsResponse beforeRestart = AssertSuccess(await browser.BrowseAsync(BrowseRequest()));
+        Assert.Equal(initialSession.ListingId, Assert.Single(beforeRestart.Items).ListingId);
+        Stopwatch restart = Stopwatch.StartNew();
+        await first.DisposeAsync();
+
+        RendezvousClientResult<BrowseSessionsResponse> unavailable = await browser.BrowseAsync(BrowseRequest());
+        Assert.False(unavailable.IsSuccess);
+        Assert.Equal(RendezvousErrorCode.ServiceUnavailable, unavailable.Error);
+
+        await using ClientTestHost second = await ClientTestHost.StartAsync(address);
+        RendezvousClientResult<PublishedSession> reregistered = await publisher.RegisterAsync(
+            CreateRegistration(101),
+            second.PublisherCredential);
+        PublishedSession replacementSession = AssertSuccess(reregistered);
+        Assert.NotEqual(initialSession.ListingId, replacementSession.ListingId);
+        BindPresence(second, replacementSession, 41_101);
+        BrowseSessionsResponse afterRestart = AssertSuccess(await browser.BrowseAsync(BrowseRequest()));
+        Assert.Equal(replacementSession.ListingId, Assert.Single(afterRestart.Items).ListingId);
+        Assert.DoesNotContain(afterRestart.Items, item => item.ListingId == initialSession.ListingId);
+        Assert.True(
+            restart.Elapsed < TimeSpan.FromSeconds(5),
+            $"Local restart and host re-registration took {restart.Elapsed}.");
+    }
+
     [Fact]
     public async Task PublisherAndBrowserClientsCompleteTheRealSessionLifecycleAndPaging()
     {
@@ -102,6 +148,27 @@ public sealed class RendezvousClientIntegrationTests
         return Assert.IsAssignableFrom<T>(result.Value);
     }
 
+    private static void BindPresence(ClientTestHost host, PublishedSession session, int port)
+    {
+        Assert.True(host.Capabilities.TryFingerprint(
+            session.HostPresenceCapability,
+            out SecretFingerprint fingerprint));
+        Assert.Equal(StoreResultCode.Success, host.Store.BindHostPresence(new(
+            session.HostPresenceHandle,
+            fingerprint,
+            new(AddressFamilyKind.Ipv4, "203.0.113.80", port),
+            null)).Code);
+    }
+
+    private static BrowseSessionsRequest BrowseRequest() => new()
+    {
+        GameId = new("space-game"),
+        EnvironmentId = new("production"),
+        RegionId = new("eu-central"),
+        ProtocolVersion = 7,
+        PageSize = 10,
+    };
+
     private static RegisterSessionRequest CreateRegistration(int index) => new()
     {
         IdempotencyKey = $"sdk-integration-{index}",
@@ -139,7 +206,7 @@ public sealed class RendezvousClientIntegrationTests
         internal EphemeralCapabilityIssuer Capabilities { get; }
         internal string PublisherCredential { get; }
 
-        internal static async Task<ClientTestHost> StartAsync()
+        internal static async Task<ClientTestHost> StartAsync(string? bindAddress = null)
         {
             ManualRendezvousClock clock = new(ProvisioningTestData.Now);
             EphemeralStoreOptions stateOptions = new();
@@ -153,7 +220,7 @@ public sealed class RendezvousClientIntegrationTests
             string credential = provisioning.Credentials.Issue(principal, clock.UtcNow);
 
             WebApplicationBuilder builder = WebApplication.CreateBuilder();
-            builder.WebHost.UseUrls("http://127.0.0.1:0");
+            builder.WebHost.UseUrls(bindAddress ?? "http://127.0.0.1:0");
             builder.Services.ConfigureHttpJsonOptions(static options =>
                 ContractJson.Configure(options.SerializerOptions));
             builder.Services.Configure<RouteHandlerOptions>(static options =>
@@ -180,10 +247,10 @@ public sealed class RendezvousClientIntegrationTests
             app.MapRendezvousContractEndpoints();
             await app.StartAsync();
             IServer server = app.Services.GetRequiredService<IServer>();
-            string address = Assert.Single(server.Features.Get<IServerAddressesFeature>()!.Addresses);
+            string serviceAddress = Assert.Single(server.Features.Get<IServerAddressesFeature>()!.Addresses);
             return new(
                 app,
-                new HttpClient { BaseAddress = new Uri(address) },
+                new HttpClient { BaseAddress = new Uri(serviceAddress) },
                 store,
                 capabilities,
                 credential);
@@ -196,4 +263,13 @@ public sealed class RendezvousClientIntegrationTests
             await _application.DisposeAsync();
         }
     }
+
+    private static int ReserveTcpPort()
+    {
+        TcpListener listener = new(IPAddress.Loopback, 0);
+        listener.Start();
+        int port = ((IPEndPoint)listener.LocalEndpoint).Port;
+        listener.Stop();
+        return port;
+    }
 }