feat: add presence-gated session leases (#7)

Closes #7

src/FinalFactory.Rendezvous.Server/Program.cs

@@ -2,6 +2,7 @@ using System.Net;
 using FinalFactory.Rendezvous.Contracts;
 using FinalFactory.Rendezvous.Server.Http;
 using FinalFactory.Rendezvous.Server.Provisioning;
+using FinalFactory.Rendezvous.Server.Sessions;
 using FinalFactory.Rendezvous.Server.State;
 using FinalFactory.Rendezvous.Server.Transport;
 using Microsoft.OpenApi;
@@ -13,6 +14,7 @@ bool isOpenApiGeneration = string.Equals(
     StringComparison.Ordinal);
 
 builder.Services.AddOpenApi("v1", static options =>
+{
     options.AddSchemaTransformer(static (schema, context, cancellationToken) =>
     {
         Type type = context.JsonTypeInfo.Type;
@@ -32,16 +34,65 @@ builder.Services.AddOpenApi("v1", static options =>
         }
 
         return Task.CompletedTask;
-    }));
+    });
+    options.AddDocumentTransformer(static (document, context, cancellationToken) =>
+    {
+        const string schemeName = "PublisherBearer";
+        document.Components ??= new OpenApiComponents();
+        document.Components.SecuritySchemes ??=
+            new Dictionary<string, IOpenApiSecurityScheme>(StringComparer.Ordinal);
+        document.Components.SecuritySchemes[schemeName] = new OpenApiSecurityScheme
+        {
+            Type = SecuritySchemeType.Http,
+            Scheme = "bearer",
+            BearerFormat = "rv1 publisher credential",
+            Description = "Tenant-scoped publisher credential issued during game provisioning.",
+        };
+
+        HashSet<string> securedOperations = new(StringComparer.Ordinal)
+        {
+            "RegisterSession",
+            "RenewSessionLease",
+            "UpdateSession",
+            "DeleteSession",
+        };
+        OpenApiSecuritySchemeReference reference = new(schemeName, document, null);
+        foreach (OpenApiPathItem path in document.Paths.Values)
+        {
+            if (path.Operations is null)
+            {
+                continue;
+            }
+
+            foreach (OpenApiOperation operation in path.Operations.Values.Where(
+                         operation => securedOperations.Contains(operation.OperationId ?? string.Empty)))
+            {
+                operation.Security ??= [];
+                operation.Security.Add(new OpenApiSecurityRequirement
+                {
+                    [reference] = [],
+                });
+            }
+        }
+
+        return Task.CompletedTask;
+    });
+});
 builder.Services.ConfigureHttpJsonOptions(static options =>
     ContractJson.Configure(options.SerializerOptions));
+builder.Services.Configure<RouteHandlerOptions>(static options =>
+    options.ThrowOnBadRequest = true);
+builder.Services.AddProblemDetails();
+builder.Services.AddExceptionHandler<RendezvousExceptionHandler>();
 
 SystemRendezvousClock rendezvousClock = new();
+EphemeralStoreOptions stateOptions = new();
 InMemoryEphemeralRendezvousStore stateStore = new(
-    new EphemeralStoreOptions(),
+    stateOptions,
     rendezvousClock,
     rendezvousClock);
 builder.Services.AddSingleton<IEphemeralRendezvousStore>(stateStore);
+builder.Services.AddSingleton<IWallClock>(rendezvousClock);
 
 if (isOpenApiGeneration)
 {
@@ -63,6 +114,11 @@ else
     builder.Services.AddSingleton(provisioning.Policies);
     builder.Services.AddSingleton(provisioning.Credentials);
     builder.Services.AddSingleton(provisioning.PublisherAuthorization);
+    EphemeralCapabilityIssuer sessionCapabilities = new();
+    builder.Services.AddSingleton(sessionCapabilities);
+    builder.Services.AddSingleton<ISessionCapabilityService>(sessionCapabilities);
+    builder.Services.AddSingleton(SessionLeaseTiming.From(stateOptions));
+    builder.Services.AddSingleton<SessionLeaseService>();
     builder.Services.AddSingleton(new ProvisioningReadiness(true));
 }
 
@@ -84,6 +140,7 @@ if (!isOpenApiGeneration)
 WebApplication app = builder.Build();
 app.Lifetime.ApplicationStopping.Register(() => stateStore.BeginDrain());
 
+app.UseExceptionHandler();
 app.MapOpenApi();
 app.MapRendezvousContractEndpoints();
 app.MapGet(