fix(external-system-gateway): resolve ExternalSystemGateway-011 — name-keyed repository lookups replace fetch-all-then-filter on the call hot path

tests/ScadaLink.ConfigurationDatabase.Tests/RepositoryCoverageTests.cs

@@ -76,6 +76,94 @@ public class ExternalSystemRepositoryTests : IDisposable
     {
         Assert.Throws<ArgumentNullException>(() => new ExternalSystemRepository(null!));
     }
+
+    // ── ExternalSystemGateway-011: name-keyed repository lookups ──
+
+    [Fact]
+    public async Task GetExternalSystemByName_ReturnsMatchingRow()
+    {
+        await _repository.AddExternalSystemAsync(
+            new ExternalSystemDefinition("Alpha", "https://alpha.test", "ApiKey"));
+        await _repository.AddExternalSystemAsync(
+            new ExternalSystemDefinition("Beta", "https://beta.test", "Basic"));
+        await _repository.SaveChangesAsync();
+
+        var loaded = await _repository.GetExternalSystemByNameAsync("Beta");
+
+        Assert.NotNull(loaded);
+        Assert.Equal("Beta", loaded!.Name);
+        Assert.Equal("https://beta.test", loaded.EndpointUrl);
+    }
+
+    [Fact]
+    public async Task GetExternalSystemByName_MissingName_ReturnsNull()
+    {
+        await _repository.AddExternalSystemAsync(
+            new ExternalSystemDefinition("Alpha", "https://alpha.test", "ApiKey"));
+        await _repository.SaveChangesAsync();
+
+        Assert.Null(await _repository.GetExternalSystemByNameAsync("DoesNotExist"));
+    }
+
+    [Fact]
+    public async Task GetMethodByName_ReturnsMethodScopedToParentSystem()
+    {
+        var sysA = new ExternalSystemDefinition("SysA", "https://a.test", "ApiKey");
+        var sysB = new ExternalSystemDefinition("SysB", "https://b.test", "ApiKey");
+        await _repository.AddExternalSystemAsync(sysA);
+        await _repository.AddExternalSystemAsync(sysB);
+        await _repository.SaveChangesAsync();
+
+        // Same method name on two different systems — the lookup must be scoped.
+        await _repository.AddExternalSystemMethodAsync(
+            new ExternalSystemMethod("getData", "GET", "/a") { ExternalSystemDefinitionId = sysA.Id });
+        await _repository.AddExternalSystemMethodAsync(
+            new ExternalSystemMethod("getData", "POST", "/b") { ExternalSystemDefinitionId = sysB.Id });
+        await _repository.SaveChangesAsync();
+
+        var method = await _repository.GetMethodByNameAsync(sysB.Id, "getData");
+
+        Assert.NotNull(method);
+        Assert.Equal(sysB.Id, method!.ExternalSystemDefinitionId);
+        Assert.Equal("POST", method.HttpMethod);
+        Assert.Equal("/b", method.Path);
+    }
+
+    [Fact]
+    public async Task GetMethodByName_MissingMethod_ReturnsNull()
+    {
+        var sys = new ExternalSystemDefinition("SysA", "https://a.test", "ApiKey");
+        await _repository.AddExternalSystemAsync(sys);
+        await _repository.SaveChangesAsync();
+
+        Assert.Null(await _repository.GetMethodByNameAsync(sys.Id, "noSuchMethod"));
+    }
+
+    [Fact]
+    public async Task GetDatabaseConnectionByName_ReturnsMatchingRow()
+    {
+        await _repository.AddDatabaseConnectionAsync(
+            new DatabaseConnectionDefinition("Plant", "Server=plant;Database=p;"));
+        await _repository.AddDatabaseConnectionAsync(
+            new DatabaseConnectionDefinition("Historian", "Server=hist;Database=h;"));
+        await _repository.SaveChangesAsync();
+
+        var loaded = await _repository.GetDatabaseConnectionByNameAsync("Historian");
+
+        Assert.NotNull(loaded);
+        Assert.Equal("Historian", loaded!.Name);
+        Assert.Equal("Server=hist;Database=h;", loaded.ConnectionString);
+    }
+
+    [Fact]
+    public async Task GetDatabaseConnectionByName_MissingName_ReturnsNull()
+    {
+        await _repository.AddDatabaseConnectionAsync(
+            new DatabaseConnectionDefinition("Plant", "Server=plant;Database=p;"));
+        await _repository.SaveChangesAsync();
+
+        Assert.Null(await _repository.GetDatabaseConnectionByNameAsync("DoesNotExist"));
+    }
 }
 
 public class NotificationRepositoryTests : IDisposable