feat(release): add reproducible signed artifacts (#19)

src/FinalFactory.Rendezvous.Server/Operations/OperatorModels.cs

@@ -3,6 +3,7 @@ namespace FinalFactory.Rendezvous.Server.Operations;
 internal sealed record OperatorStatusResponse
 {
     public required string Status { get; init; }
+    public required OperatorCompatibilityResponse Compatibility { get; init; }
     public required OperatorReadinessResponse Readiness { get; init; }
     public required OperatorStoreResponse Store { get; init; }
     public required IReadOnlyList<OperatorTenantResponse> Tenants { get; init; }
@@ -10,6 +11,18 @@ internal sealed record OperatorStatusResponse
     public required IReadOnlyDictionary<string, long> AuditCounts { get; init; }
 }
 
+internal sealed record OperatorCompatibilityResponse
+{
+    public required string ServerVersion { get; init; }
+    public required string MinimumClientVersion { get; init; }
+    public required int MaximumClientMajorVersion { get; init; }
+    public required IReadOnlyList<int> HttpContractVersions { get; init; }
+    public required IReadOnlyList<int> UdpContractVersions { get; init; }
+    public required IReadOnlyList<int> ConnectionTicketFormatVersions { get; init; }
+    public required int LiteNetLibMajorVersion { get; init; }
+    public required string GameplayProtocolCompatibility { get; init; }
+}
+
 internal sealed record OperatorReadinessResponse
 {
     public required bool HttpListener { get; init; }

src/FinalFactory.Rendezvous.Server/Operations/OperatorService.cs

@@ -19,6 +19,7 @@ internal sealed class OperatorService(
         return new OperatorStatusResponse
         {
             Status = readinessSnapshot.IsReady ? "ready" : "not-ready",
+            Compatibility = ReleaseCompatibility.CreateResponse(),
             Readiness = new OperatorReadinessResponse
             {
                 HttpListener = readinessSnapshot.HttpListenerReady,

src/FinalFactory.Rendezvous.Server/Operations/ReleaseCompatibility.cs

@@ -0,0 +1,41 @@
+using System.Reflection;
+using FinalFactory.Rendezvous.Contracts;
+
+namespace FinalFactory.Rendezvous.Server.Operations;
+
+internal static class ReleaseCompatibility
+{
+    private static readonly Assembly ServerAssembly = typeof(ReleaseCompatibility).Assembly;
+
+    internal static string MinimumClientVersion => Metadata("RendezvousMinimumClientVersion");
+    internal static int MaximumClientMajorVersion => MetadataInteger("RendezvousMaximumClientMajorVersion");
+    internal static int UdpContractVersion => MetadataInteger("RendezvousUdpContractVersion");
+    internal static int ConnectionTicketFormatVersion => MetadataInteger("RendezvousConnectionTicketFormatVersion");
+    internal static int LiteNetLibMajorVersion => MetadataInteger("RendezvousLiteNetLibMajorVersion");
+
+    internal static OperatorCompatibilityResponse CreateResponse() => new()
+    {
+        ServerVersion = ServerAssembly
+            .GetCustomAttribute<AssemblyInformationalVersionAttribute>()?
+            .InformationalVersion.Split('+', 2)[0]
+            ?? ServerAssembly.GetName().Version?.ToString(3)
+            ?? "unknown",
+        MinimumClientVersion = MinimumClientVersion,
+        MaximumClientMajorVersion = MaximumClientMajorVersion,
+        HttpContractVersions = [ContractLimits.ContractVersion],
+        UdpContractVersions = [UdpContractVersion],
+        ConnectionTicketFormatVersions = [ConnectionTicketFormatVersion],
+        LiteNetLibMajorVersion = LiteNetLibMajorVersion,
+        GameplayProtocolCompatibility = "exact-per-tenant",
+    };
+
+    private static string Metadata(string key) => ServerAssembly
+        .GetCustomAttributes<AssemblyMetadataAttribute>()
+        .Single(attribute => string.Equals(attribute.Key, key, StringComparison.Ordinal))
+        .Value
+        ?? throw new InvalidOperationException($"Assembly metadata {key} has no value.");
+
+    private static int MetadataInteger(string key) => int.Parse(
+        Metadata(key),
+        System.Globalization.CultureInfo.InvariantCulture);
+}