feat: add response routing for service import request-reply patterns

2026-02-23 06:01:53 -05:00
parent c9066e526d
commit 4450c27381
2 changed files with 191 additions and 0 deletions
--- a/tests/NATS.Server.Tests/ResponseRoutingTests.cs
+++ b/tests/NATS.Server.Tests/ResponseRoutingTests.cs
@@ -0,0 +1,127 @@
+using NATS.Server.Auth;
+using NATS.Server.Imports;
+
+namespace NATS.Server.Tests;
+
+public class ResponseRoutingTests
+{
+    [Fact]
+    public void GenerateReplyPrefix_creates_unique_prefix()
+    {
+        var prefix1 = ResponseRouter.GenerateReplyPrefix();
+        var prefix2 = ResponseRouter.GenerateReplyPrefix();
+
+        prefix1.ShouldStartWith("_R_.");
+        prefix2.ShouldStartWith("_R_.");
+        prefix1.ShouldNotBe(prefix2);
+        prefix1.Length.ShouldBeGreaterThan(4);
+    }
+
+    [Fact]
+    public void GenerateReplyPrefix_ends_with_dot()
+    {
+        var prefix = ResponseRouter.GenerateReplyPrefix();
+
+        prefix.ShouldEndWith(".");
+        // Format: "_R_." + 10 chars + "." = 15 chars
+        prefix.Length.ShouldBe(15);
+    }
+
+    [Fact]
+    public void Singleton_response_import_removed_after_delivery()
+    {
+        var exporter = new Account("exporter");
+        exporter.AddServiceExport("api.test", ServiceResponseType.Singleton, null);
+
+        var replyPrefix = ResponseRouter.GenerateReplyPrefix();
+        var responseSi = new ServiceImport
+        {
+            DestinationAccount = exporter,
+            From = replyPrefix + ">",
+            To = "_INBOX.original.reply",
+            IsResponse = true,
+            ResponseType = ServiceResponseType.Singleton,
+        };
+        exporter.Exports.Responses[replyPrefix] = responseSi;
+
+        exporter.Exports.Responses.ShouldContainKey(replyPrefix);
+
+        // Simulate singleton delivery cleanup
+        ResponseRouter.CleanupResponse(exporter, replyPrefix, responseSi);
+
+        exporter.Exports.Responses.ShouldNotContainKey(replyPrefix);
+    }
+
+    [Fact]
+    public void CreateResponseImport_registers_in_exporter_responses()
+    {
+        var exporter = new Account("exporter");
+        var importer = new Account("importer");
+        exporter.AddServiceExport("api.test", ServiceResponseType.Singleton, null);
+
+        var originalSi = new ServiceImport
+        {
+            DestinationAccount = exporter,
+            From = "api.test",
+            To = "api.test",
+            Export = exporter.Exports.Services["api.test"],
+            ResponseType = ServiceResponseType.Singleton,
+        };
+
+        var responseSi = ResponseRouter.CreateResponseImport(exporter, originalSi, "_INBOX.abc123");
+
+        responseSi.IsResponse.ShouldBeTrue();
+        responseSi.ResponseType.ShouldBe(ServiceResponseType.Singleton);
+        responseSi.To.ShouldBe("_INBOX.abc123");
+        responseSi.DestinationAccount.ShouldBe(exporter);
+        responseSi.From.ShouldEndWith(">");
+        responseSi.Export.ShouldBe(originalSi.Export);
+
+        // Should be registered in the exporter's response map
+        exporter.Exports.Responses.Count.ShouldBe(1);
+    }
+
+    [Fact]
+    public void CreateResponseImport_preserves_streamed_response_type()
+    {
+        var exporter = new Account("exporter");
+        exporter.AddServiceExport("api.stream", ServiceResponseType.Streamed, null);
+
+        var originalSi = new ServiceImport
+        {
+            DestinationAccount = exporter,
+            From = "api.stream",
+            To = "api.stream",
+            Export = exporter.Exports.Services["api.stream"],
+            ResponseType = ServiceResponseType.Streamed,
+        };
+
+        var responseSi = ResponseRouter.CreateResponseImport(exporter, originalSi, "_INBOX.xyz789");
+
+        responseSi.ResponseType.ShouldBe(ServiceResponseType.Streamed);
+    }
+
+    [Fact]
+    public void Multiple_response_imports_each_get_unique_prefix()
+    {
+        var exporter = new Account("exporter");
+        exporter.AddServiceExport("api.test", ServiceResponseType.Singleton, null);
+
+        var originalSi = new ServiceImport
+        {
+            DestinationAccount = exporter,
+            From = "api.test",
+            To = "api.test",
+            Export = exporter.Exports.Services["api.test"],
+            ResponseType = ServiceResponseType.Singleton,
+        };
+
+        var resp1 = ResponseRouter.CreateResponseImport(exporter, originalSi, "_INBOX.reply1");
+        var resp2 = ResponseRouter.CreateResponseImport(exporter, originalSi, "_INBOX.reply2");
+
+        exporter.Exports.Responses.Count.ShouldBe(2);
+        resp1.To.ShouldBe("_INBOX.reply1");
+        resp2.To.ShouldBe("_INBOX.reply2");
+        resp1.From.ShouldNotBe(resp2.From);
+    }
+}