feat(batch28): merge jetstream-api

dotnet/src/ZB.MOM.NatsNet.Server/Accounts/Account.JetStream.cs

@@ -178,6 +178,72 @@ public sealed partial class Account
         }
     }
 
+    internal void TrackAPI()
+    {
+        _mu.EnterReadLock();
+        var jsa = JetStream;
+        _mu.ExitReadLock();
+        if (jsa is null)
+            return;
+
+        jsa.UsageLock.EnterWriteLock();
+        try
+        {
+            jsa.UsageApi++;
+            jsa.ApiTotal++;
+            jsa.SendClusterUsageUpdate();
+
+            if (jsa.Js is JetStream js)
+                Interlocked.Add(ref js.ApiTotal, 1);
+        }
+        finally
+        {
+            jsa.UsageLock.ExitWriteLock();
+        }
+    }
+
+    internal void TrackAPIErr()
+    {
+        _mu.EnterReadLock();
+        var jsa = JetStream;
+        _mu.ExitReadLock();
+        if (jsa is null)
+            return;
+
+        jsa.UsageLock.EnterWriteLock();
+        try
+        {
+            jsa.UsageApi++;
+            jsa.ApiTotal++;
+            jsa.UsageErr++;
+            jsa.ApiErrors++;
+            jsa.SendClusterUsageUpdate();
+
+            if (jsa.Js is JetStream js)
+            {
+                Interlocked.Add(ref js.ApiTotal, 1);
+                Interlocked.Add(ref js.ApiErrors, 1);
+            }
+        }
+        finally
+        {
+            jsa.UsageLock.ExitWriteLock();
+        }
+    }
+
+    internal (bool Enabled, bool ShouldError) CheckJetStream()
+    {
+        _mu.EnterReadLock();
+        try
+        {
+            return (JetStream is not null, _nleafs + _nrleafs == 0);
+        }
+        finally
+        {
+            _mu.ExitReadLock();
+        }
+    }
+
     internal (bool MaxBytesRequired, long MaxStreamBytes) MaxBytesLimits(StreamConfig? cfg)
     {
         _mu.EnterReadLock();
@@ -530,4 +596,22 @@ public sealed partial class Account
 
         return EnableAllJetStreamServiceImportsAndMappings();
     }
+
+    internal Exception? JsNonClusteredStreamLimitsCheck(StreamConfig config)
+    {
+        var (server, jsa, err) = CheckForJetStream();
+        if (err is not null || server is null || jsa is null)
+            return err ?? new InvalidOperationException("jetstream not enabled for account");
+
+        var selected = jsa.SelectLimits(config.Replicas);
+        if (!selected.Found)
+            return new InvalidOperationException(JsApiErrors.NewJSNoLimitsError().Description ?? "jetstream limits not configured");
+
+        var reservation = jsa.TieredReservation(selected.Tier, config);
+        var js = server.GetJetStream();
+        if (js is null)
+            return new InvalidOperationException("jetstream not enabled");
+
+        return js.CheckAccountLimits(selected.Limits, config, reservation);
+    }
 }

dotnet/src/ZB.MOM.NatsNet.Server/JetStream/JetStreamApi.cs

@@ -0,0 +1,190 @@
+using System.Text.Json;
+using System.Text.Json.Serialization;
+using ZB.MOM.NatsNet.Server.Internal.DataStructures;
+
+namespace ZB.MOM.NatsNet.Server;
+
+internal delegate void JetStreamApiHandler(ClientConnection c, Account acc, string subject, string reply, byte[] message);
+
+internal sealed class JetStreamApiSubscription
+{
+    public required string Subject { get; init; }
+    public required JetStreamApiHandler Handler { get; init; }
+}
+
+internal sealed class JsApiRoutedRequest
+{
+    public required JetStreamApiSubscription Subscription { get; init; }
+    public required Account Account { get; init; }
+    public required string Subject { get; init; }
+    public required string Reply { get; init; }
+    public required byte[] Message { get; init; }
+}
+
+internal sealed class DelayedApiResponse
+{
+    public ClientInfo? ClientInfo { get; init; }
+    public required Account Account { get; init; }
+    public required string Subject { get; init; }
+    public required string Reply { get; init; }
+    public string Request { get; init; } = string.Empty;
+    public byte[]? Header { get; init; }
+    public required string Response { get; init; }
+    public DateTime DeadlineUtc { get; init; }
+    public bool RawResponse { get; init; }
+    public DelayedApiResponse? Next { get; set; }
+}
+
+internal static class JetStreamApi
+{
+    internal static readonly TimeSpan ErrorResponseDelay = TimeSpan.FromMilliseconds(500);
+
+    internal static Dictionary<string, string> GenerateJSMappingTable(string domain)
+    {
+        var mappings = new Dictionary<string, string>(StringComparer.Ordinal)
+        {
+            ["INFO"] = JsApiSubjects.JsApiAccountInfo,
+            ["STREAM.>"] = "$JS.API.STREAM.>",
+            ["CONSUMER.>"] = "$JS.API.CONSUMER.>",
+            ["DIRECT.>"] = "$JS.API.DIRECT.>",
+            ["META.>"] = "$JS.API.META.>",
+            ["SERVER.>"] = "$JS.API.SERVER.>",
+            ["ACCOUNT.>"] = "$JS.API.ACCOUNT.>",
+            ["$KV.>"] = "$KV.>",
+            ["$OBJ.>"] = "$OBJ.>",
+        };
+
+        var table = new Dictionary<string, string>(StringComparer.Ordinal);
+        foreach (var (suffix, target) in mappings)
+            table[$"$JS.{domain}.API.{suffix}"] = target;
+
+        return table;
+    }
+
+    internal static void AddDelayedResponse(ref DelayedApiResponse? head, ref DelayedApiResponse? tail, DelayedApiResponse response)
+    {
+        if (head is null)
+        {
+            head = response;
+            tail = response;
+            return;
+        }
+
+        if (tail is not null && response.DeadlineUtc >= tail.DeadlineUtc)
+        {
+            tail.Next = response;
+            tail = response;
+            return;
+        }
+
+        DelayedApiResponse? previous = null;
+        for (var current = head; current is not null; current = current.Next)
+        {
+            if (response.DeadlineUtc < current.DeadlineUtc)
+            {
+                response.Next = current;
+                if (previous is null)
+                    head = response;
+                else
+                    previous.Next = response;
+                return;
+            }
+
+            previous = current;
+        }
+
+        if (tail is not null)
+            tail.Next = response;
+        tail = response;
+    }
+
+    internal static string StreamNameFromSubject(string subject) =>
+        SubscriptionIndex.TokenAt(subject, 5);
+
+    internal static string ConsumerNameFromSubject(string subject) =>
+        SubscriptionIndex.TokenAt(subject, 6);
+
+    internal static bool IsJSONObjectOrArray(ReadOnlySpan<byte> payload)
+    {
+        for (var i = 0; i < payload.Length; i++)
+        {
+            var ch = payload[i];
+            if (ch is (byte)' ' or (byte)'\t' or (byte)'\r' or (byte)'\n')
+                continue;
+
+            return ch is (byte)'{' or (byte)'[';
+        }
+
+        return false;
+    }
+
+    internal static bool IsEmptyRequest(ReadOnlySpan<byte> payload)
+    {
+        if (payload.IsEmpty)
+            return true;
+
+        var start = 0;
+        var end = payload.Length - 1;
+        while (start < payload.Length && payload[start] is (byte)' ' or (byte)'\t' or (byte)'\r' or (byte)'\n')
+            start++;
+        while (end >= start && payload[end] is (byte)' ' or (byte)'\t' or (byte)'\r' or (byte)'\n')
+            end--;
+        if (end < start)
+            return true;
+
+        var trimmed = payload.Slice(start, end - start + 1);
+        if (trimmed.SequenceEqual("{}"u8))
+            return true;
+
+        try
+        {
+            using var document = JsonDocument.Parse(trimmed.ToArray());
+            return document.RootElement.ValueKind == JsonValueKind.Object &&
+                   !document.RootElement.EnumerateObject().Any();
+        }
+        catch
+        {
+            return false;
+        }
+    }
+
+    internal static bool SubjectMatches(string pattern, string subject)
+    {
+        var p = pattern.Split('.', StringSplitOptions.None);
+        var s = subject.Split('.', StringSplitOptions.None);
+
+        for (var i = 0; i < p.Length; i++)
+        {
+            if (i >= s.Length)
+                return p[i] == ">";
+
+            var token = p[i];
+            if (token == ">")
+                return true;
+            if (token == "*")
+                continue;
+            if (!string.Equals(token, s[i], StringComparison.Ordinal))
+                return false;
+        }
+
+        return p.Length == s.Length;
+    }
+
+    internal static T? DeserializeStrict<T>(byte[] payload, bool strictMode)
+    {
+        var strictOptions = new JsonSerializerOptions
+        {
+            PropertyNameCaseInsensitive = true,
+            UnmappedMemberHandling = JsonUnmappedMemberHandling.Disallow,
+        };
+
+        try
+        {
+            return JsonSerializer.Deserialize<T>(payload, strictOptions);
+        }
+        catch when (!strictMode)
+        {
+            return JsonSerializer.Deserialize<T>(payload);
+        }
+    }
+}

dotnet/src/ZB.MOM.NatsNet.Server/JetStream/JetStreamEngine.cs

@@ -1,3 +1,6 @@
+using System.Text;
+using ZB.MOM.NatsNet.Server.Internal;
+
 namespace ZB.MOM.NatsNet.Server;
 
 internal sealed class JetStreamEngine(JetStream state)
@@ -7,6 +10,7 @@ internal sealed class JetStreamEngine(JetStream state)
     private const string JsWillExtend = "will_extend";
     private const string JsNoExtend = "no_extend";
     private const string JsDomainApiTemplate = "$JS.{0}.API.>";
+    private const string JsApiAccountPrefix = "$JS.API.ACCOUNT.";
 
     internal void SetStarted()
     {
@@ -21,6 +25,91 @@ internal sealed class JetStreamEngine(JetStream state)
         }
     }
 
+    internal void ApiDispatch(ClientConnection c, Account acc, string subject, string reply, byte[] rawMessage)
+    {
+        // These meta/system directives are handled elsewhere.
+        if (subject == JsApiSubjects.JsApiLeaderStepDown ||
+            subject == JsApiSubjects.JsApiRemoveServer ||
+            subject.StartsWith(JsApiAccountPrefix, StringComparison.Ordinal))
+        {
+            return;
+        }
+
+        if (_state.Server is not NatsServer server)
+            return;
+
+        var route = server.MatchJetStreamApiSubscription(subject);
+        var (header, payload) = c.MsgParts(rawMessage);
+        var requestBody = Encoding.UTF8.GetString(payload);
+
+        if (NatsMessageHeaders.GetHeader(AccountEventConstants.ClientInfoHeader, header) is not { Length: > 0 })
+        {
+            var systemAccount = server.SystemAccount();
+            if (!ReferenceEquals(systemAccount, acc))
+                return;
+
+            if (subject != JsApiSubjects.JsApiAccountInfo)
+            {
+                if (c.Kind is ClientKind.Client or ClientKind.Leaf)
+                {
+                    var response = new ApiResponse
+                    {
+                        Type = JsApiSubjects.JsApiSystemResponseType,
+                        Error = JsApiErrors.NewJSNotEnabledForAccountError(),
+                    };
+                    server.SendAPIErrResponse(null, acc, subject, reply, requestBody, server.JsonResponse(response));
+                }
+
+                return;
+            }
+        }
+
+        if (route is null)
+        {
+            if (c.Kind is ClientKind.Client or ClientKind.Leaf)
+            {
+                var (_, requestAcc, _, _, _) = server.GetRequestInfo(c, rawMessage);
+                if (requestAcc is not null && !ReferenceEquals(requestAcc, server.SystemAccount()))
+                {
+                    var response = new ApiResponse
+                    {
+                        Type = JsApiSubjects.JsApiSystemResponseType,
+                        Error = JsApiErrors.NewJSBadRequestError(),
+                    };
+                    server.SendAPIErrResponse(null, requestAcc, subject, reply, requestBody, server.JsonResponse(response));
+                }
+            }
+
+            return;
+        }
+
+        Interlocked.Add(ref _state.ApiInflight, 1);
+
+        var request = new JsApiRoutedRequest
+        {
+            Subscription = route,
+            Account = acc,
+            Subject = subject,
+            Reply = reply,
+            Message = rawMessage.ToArray(),
+        };
+
+        var (queued, dropped) = server.EnqueueJSApiRequest(_state, request);
+        if (!queued)
+        {
+            if (dropped > 0)
+            {
+                server.PublishAdvisory(
+                    server.SystemAccount(),
+                    JsApiSubjects.JsAdvisoryApiLimitReached,
+                    new { Type = "io.nats.jetstream.advisory.v1.api_limit_reached", Dropped = dropped, Time = DateTime.UtcNow });
+            }
+
+            route.Handler(c, acc, subject, reply, rawMessage);
+            Interlocked.Add(ref _state.ApiInflight, -1);
+        }
+    }
+
     internal bool IsEnabled() => Interlocked.CompareExchange(ref _state.Disabled, 0, 0) == 0;
 
     internal void SetJetStreamStandAlone(bool isStandAlone)

dotnet/src/ZB.MOM.NatsNet.Server/JetStream/JsAccount.Core.cs

@@ -245,6 +245,38 @@ internal sealed partial class JsAccount
         }
     }
 
+    internal long TieredReservation(string tier, StreamConfig cfg)
+    {
+        long reservation = 0;
+
+        Lock.EnterReadLock();
+        try
+        {
+            foreach (var stream in Streams.Values.OfType<NatsStream>())
+            {
+                var streamCfg = stream.Config;
+                if (streamCfg.MaxBytes <= 0 || string.Equals(streamCfg.Name, cfg.Name, StringComparison.Ordinal))
+                    continue;
+
+                if (string.IsNullOrEmpty(tier))
+                {
+                    if (streamCfg.Storage == cfg.Storage)
+                        reservation += Math.Max(1, streamCfg.Replicas) * streamCfg.MaxBytes;
+                    continue;
+                }
+
+                if (streamCfg.Replicas == cfg.Replicas && JetStreamEngine.IsSameTier(streamCfg, cfg))
+                    reservation += Math.Max(1, streamCfg.Replicas) * streamCfg.MaxBytes;
+            }
+
+            return reservation;
+        }
+        finally
+        {
+            Lock.ExitReadLock();
+        }
+    }
+
     internal (ulong Mem, ulong Store) StorageTotals()
     {
         UsageLock.EnterReadLock();

dotnet/src/ZB.MOM.NatsNet.Server/NatsServer.JetStreamCore.cs

@@ -268,11 +268,7 @@ public sealed partial class NatsServer
 
     internal void SetupJetStreamExports()
     {
-        var sys = SystemAccount();
-        if (sys == null)
-            return;
-
-        var err = sys.AddServiceExport(JsApiSubjects.JsAllApi, null);
+        var err = SetJetStreamExportSubs();
         if (err != null)
             Warnf("Error setting up jetstream service exports: {0}", err.Message);
     }

dotnet/tests/ZB.MOM.NatsNet.Server.Tests/ImplBacklog/JetStreamEngineTests.cs

@@ -15,6 +15,72 @@ public sealed class JetStreamEngineTests
         err!.Message.ShouldContain("unavailable");
     }
 
+
+    [Fact] // T:1716
+    public void IsJSONObjectOrArray_ShouldSucceed()
+    {
+        var tests = new (string Name, byte[] Data, bool Valid)[]
+        {
+            ("empty", [], false),
+            ("empty_object", "{}"u8.ToArray(), true),
+            ("empty object, not trimmed", "\t\n\r{ }"u8.ToArray(), true),
+            ("empty_array", "[]"u8.ToArray(), true),
+            ("empty array, not trimmed", "\t\n\r[ ]"u8.ToArray(), true),
+            ("empty_string", "\"\""u8.ToArray(), false),
+            ("whitespace_only", "   "u8.ToArray(), false),
+            ("object_with_whitespace", "{   }"u8.ToArray(), true),
+            ("array_with_whitespace", "[   ]"u8.ToArray(), true),
+            ("string_with_whitespace", "   \"text\""u8.ToArray(), false),
+            ("number", "123"u8.ToArray(), false),
+            ("boolean_true", "true"u8.ToArray(), false),
+            ("boolean_false", "false"u8.ToArray(), false),
+            ("null_value", "null"u8.ToArray(), false),
+            ("invalid_json", "invalid"u8.ToArray(), false),
+        };
+
+        foreach (var test in tests)
+        {
+            JetStreamApi.IsJSONObjectOrArray(test.Data).ShouldBe(test.Valid, test.Name);
+        }
+    }
+
+    [Fact] // T:1719
+    public void JetStreamDelayedAPIResponses_ShouldSucceed()
+    {
+        var account = new Account { Name = "ACC" };
+        DelayedApiResponse? head = null;
+        DelayedApiResponse? tail = null;
+        var now = DateTime.UtcNow;
+
+        var responses = new[]
+        {
+            NewDelayed(account, "request2", "response2", now.AddMilliseconds(500)),
+            NewDelayed(account, "request1", "response1", now.AddMilliseconds(200)),
+            NewDelayed(account, "request4", "response4", now.AddMilliseconds(800)),
+            NewDelayed(account, "request3", "response3", now.AddMilliseconds(650)),
+        };
+
+        foreach (var response in responses)
+            JetStreamApi.AddDelayedResponse(ref head, ref tail, response);
+
+        var orderedRequests = new List<string>();
+        for (var current = head; current is not null; current = current.Next)
+            orderedRequests.Add(current.Request);
+
+        orderedRequests.ShouldBe(["request1", "request2", "request3", "request4"]);
+    }
+
+    private static DelayedApiResponse NewDelayed(Account account, string request, string response, DateTime deadlineUtc) =>
+        new()
+        {
+            Account = account,
+            Subject = "SUB",
+            Reply = string.Empty,
+            Request = request,
+            Response = response,
+            DeadlineUtc = deadlineUtc,
+        };
+
     [Fact] // T:1477
     public void JetStreamMaxConsumers_ShouldSucceed()
     {

reports/current.md

@@ -1,6 +1,6 @@
 # NATS .NET Porting Status Report
 
-Generated: 2026-03-01 03:33:10 UTC
+Generated: 2026-03-01 03:41:45 UTC
 
 ## Modules (12 total)