feat(esg): {param} path-template substitution with consumed-param removal — implements the spec'd /recipes/{id} form

Claude-Session: https://claude.ai/code/session_01MtdgwpEeCUn6cUA5f1LMPj
2026-07-10 04:14:13 -04:00
parent d0b27b8957
commit eb7a913d22
3 changed files with 134 additions and 7 deletions
@@ -1114,4 +1114,79 @@ public class ExternalSystemClientTests

        Assert.True(result.Success);
    }
+
+    // ── ExternalSystemGateway: {param} path-template substitution ──
+
+    [Fact]
+    public async Task PathTemplate_SubstitutesAndConsumesParameter()
+    {
+        // A `{id}` placeholder in the method path is replaced with the escaped
+        // parameter value and the consumed name is removed from the query string.
+        var system = new ExternalSystemDefinition("TestAPI", "https://api.example.com", "none") { Id = 1 };
+        var method = new ExternalSystemMethod("getRecipe", "GET", "/recipes/{id}") { Id = 1, ExternalSystemDefinitionId = 1 };
+        StubResolution(system, method);
+
+        var handler = new RequestCapturingHandler(HttpStatusCode.OK, "{}");
+        _httpClientFactory.CreateClient(Arg.Any<string>()).Returns(new HttpClient(handler));
+
+        var client = new ExternalSystemClient(
+            _httpClientFactory, _repository, NullLogger<ExternalSystemClient>.Instance);
+
+        await client.CallAsync("TestAPI", "getRecipe", new Dictionary<string, object?>
+        {
+            ["id"] = "R 1",
+            ["filter"] = "x",
+        });
+
+        var uri = handler.LastUri!.AbsoluteUri;
+        // The value is substituted into the path (escaped) and consumed — it must
+        // NOT reappear in the query string; the remaining parameter still does.
+        Assert.Equal("https://api.example.com/recipes/R%201?filter=x", uri);
+        Assert.DoesNotContain("id=", uri);
+    }
+
+    [Fact]
+    public async Task PathTemplate_Post_ConsumedParamExcludedFromBody()
+    {
+        // A path-template parameter consumed by a POST path must not also be
+        // serialized into the JSON body.
+        var system = new ExternalSystemDefinition("TestAPI", "https://api.example.com", "none") { Id = 1 };
+        var method = new ExternalSystemMethod("addLine", "POST", "/orders/{orderId}/lines") { Id = 1, ExternalSystemDefinitionId = 1 };
+        StubResolution(system, method);
+
+        var handler = new RequestCapturingHandler(HttpStatusCode.OK, "{}");
+        _httpClientFactory.CreateClient(Arg.Any<string>()).Returns(new HttpClient(handler));
+
+        var client = new ExternalSystemClient(
+            _httpClientFactory, _repository, NullLogger<ExternalSystemClient>.Instance);
+
+        await client.CallAsync("TestAPI", "addLine", new Dictionary<string, object?>
+        {
+            ["orderId"] = 5,
+            ["qty"] = 2,
+        });
+
+        Assert.Equal("https://api.example.com/orders/5/lines", handler.LastUri!.ToString());
+        Assert.Contains("\"qty\":2", handler.LastBody);
+        Assert.DoesNotContain("orderId", handler.LastBody);
+    }
+
+    [Fact]
+    public async Task PathTemplate_MissingParameter_ThrowsClearError()
+    {
+        // A `{id}` placeholder with no matching parameter is an authoring error —
+        // reject it with a clear ArgumentException naming the placeholder.
+        var system = new ExternalSystemDefinition("TestAPI", "https://api.example.com", "none") { Id = 1 };
+        var method = new ExternalSystemMethod("getRecipe", "GET", "/recipes/{id}") { Id = 1, ExternalSystemDefinitionId = 1 };
+        StubResolution(system, method);
+
+        _httpClientFactory.CreateClient(Arg.Any<string>()).Returns(new HttpClient(new RequestCapturingHandler(HttpStatusCode.OK, "{}")));
+
+        var client = new ExternalSystemClient(
+            _httpClientFactory, _repository, NullLogger<ExternalSystemClient>.Instance);
+
+        var ex = await Assert.ThrowsAsync<ArgumentException>(
+            () => client.CallAsync("TestAPI", "getRecipe"));
+        Assert.Contains("id", ex.Message);
+    }
 }