feat(modbus-rtu): bind Transport mode on options/DTO/factory (string-enum guard)

Claude-Session: https://claude.ai/code/session_01GASWkNEi68FSCtvr6rLoEW
2026-07-24 14:04:34 -04:00
parent 47e9cd56ef
commit 20be5416b9
3 changed files with 59 additions and 0 deletions
@@ -0,0 +1,47 @@
+using System.Text.Json;
+using System.Text.Json.Serialization;
+using Shouldly;
+using Xunit;
+
+namespace ZB.MOM.WW.OtOpcUa.Driver.Modbus.Tests;
+
+public sealed class ModbusTransportConfigRoundTripTests
+{
+    // Mirrors the AdminUI ModbusDriverForm serializer: camelCase + string enums.
+    private static readonly JsonSerializerOptions _adminOpts = new()
+    {
+        PropertyNamingPolicy = JsonNamingPolicy.CamelCase,
+        Converters = { new JsonStringEnumConverter() },
+    };
+
+    [Fact]
+    public void Transport_serializes_as_a_string_not_a_number()
+    {
+        var opts = new ModbusDriverOptions { Host = "10.20.0.50", Port = 4001, Transport = ModbusTransportMode.RtuOverTcp };
+        var json = JsonSerializer.Serialize(opts, _adminOpts);
+        json.ShouldContain("\"transport\":\"RtuOverTcp\"");
+        json.ShouldNotContain("\"transport\":1", Case.Sensitive);
+    }
+
+    [Fact]
+    public void Factory_binds_RtuOverTcp_from_string_config()
+    {
+        const string json = """{ "host": "10.20.0.50", "port": 4001, "transport": "RtuOverTcp" }""";
+        using var driver = ModbusDriverFactoryExtensions.CreateInstance("mb-rtu", json);
+        var opts = (ModbusDriverOptions)typeof(ModbusDriver)
+            .GetField("_options", System.Reflection.BindingFlags.NonPublic | System.Reflection.BindingFlags.Instance)!
+            .GetValue(driver)!;
+        opts.Transport.ShouldBe(ModbusTransportMode.RtuOverTcp);
+    }
+
+    [Fact]
+    public void Factory_defaults_Transport_to_Tcp_when_omitted()
+    {
+        const string json = """{ "host": "10.0.0.10" }""";
+        using var driver = ModbusDriverFactoryExtensions.CreateInstance("mb-tcp", json);
+        var opts = (ModbusDriverOptions)typeof(ModbusDriver)
+            .GetField("_options", System.Reflection.BindingFlags.NonPublic | System.Reflection.BindingFlags.Instance)!
+            .GetValue(driver)!;
+        opts.Transport.ShouldBe(ModbusTransportMode.Tcp);
+    }
+}